run_case.sh 标准用例规格

轻重载内存压力下"申请一块匿名内存"的耗时测量 —— iOS / Linux 同一步骤 · 输出格式强约束

纯 POSIX sh无 awk/bc 依赖key=value 记录 pre_* 申请前快照配对iOS(dash) / Linux / macOS 实测

用例目标

  • 测什么:申请一块匿名内存的耗时 —— touch 模式 = mmap + 首触缺页(纯申请); memset 模式 = mmap + 整块写入(申请 + 写入)。
  • 怎么对比:轻载与重载的唯一差异是 -b ballast 参数;重载时 harness 自动 建 ballast → 等压力稳定 → 测量 → 自动释放,全程同一套命令。
  • 关键约束:每轮测量前先快照系统内存,申请耗时与申请时刻前的内存统计值逐轮配对成 一条 REC 记录 —— 耗时永远可以溯源到"当时系统处于什么状态"。
  • 跨平台:iOS(越狱)与 Linux 用完全相同的步骤;harness 为纯 POSIX sh (bash 3.2 / zsh / dash / Ubuntu sh 实测通过),不依赖 awk/bc/python。

环境准备

平台编译部署要点
Linuxmake产物与 run_case.sh 放同一目录即可
macOS (调试用)make同上;与 iOS 共用 Darwin 分支 (vm_stat)
iOS (越狱)make iosscp 到设备后设备端 /usr/bin/ldid -S<ents.plist> 签名 + chmod +x(Mac 侧签名会 SIGKILL)

运行依赖:sh、date、uname、kill、 内存源(Darwin: vm_stat + sysctl;Linux: /proc/meminfo)。

用例步骤(标准序列)

标准四步size 按需替换,此处 200M
# ① 轻载基线(系统空闲态)
sh ./run_case.sh -s 200M -m touch  -r 5          > case-light-touch.txt
sh ./run_case.sh -s 200M -m memset -r 5          > case-light-memset.txt

# ② 重载(自动: 建 ballast → 等稳定 → 测量 → 释放)
sh ./run_case.sh -s 200M -m touch  -r 5 -b 3600  > case-heavy-touch.txt
sh ./run_case.sh -s 200M -m memset -r 5 -b 3600  > case-heavy-memset.txt

# iOS 远程执行(例):
ssh -p 2222 root@localhost 'cd /var/mobile/ios_memslice && sh ./run_case.sh -s 200M -m touch -r 5 -b 3600'

参数

参数默认含义
-s200M申请大小,仅整 MiB(如 64M / 200M / 500M)
-mtouchtouch = 纯申请(首触缺页);memset = 申请 + 写入
-r5轮数;每轮独立配对一次申请前内存快照
-b0ballast(MiB);>0 时自动建压/释放(mem_stress -P 50)
-w20ballast 压力稳定等待秒数
-t900ballast 死开关(秒)—— SSH 失联也能自愈
ballast 取值:物理内存的 45%~60%(6GB 手机 ≈ 2700~3600)。 必须用 -P 50 半随机填充(压缩比 ~2:1,压缩器有余量)——不可压缩的全随机填充会塞满 XNU 压缩器导致 watchdog 内核 panic(实测事故见主页实验报告)。
内置安全机制:① -t 死开关到期自动释放;② 稳定期 free < 16MiB 自动中止(exit 3); ③ ballast 进程异常退出立即中止;④ trap EXIT/INT/TERM 保证任何路径下释放 ballast。

输出格式约束

输出为行式记录:每行一类,行首是记录类型标签,后接空格分隔的 key=value 令牌。 除 ERROR 行可含自由文本外,所有值不含空格。

记录类型

行类型时机作用
CASE每次调用开头,恰好一行用例元数据(平台/内核/规模/模式/轮数/ballast)
PHASE阶段切换生命周期与阶段级内存快照(pre_;释放用 post_)
REC每轮测量一行申请耗时 + 缺页次数 + 申请前/驻留时内存统计(核心记录)
SUMMARY测量结束fill_ms 的 avg/min/max(可由 REC 重算)
ERROR异常ERROR code=<名称> ...;退出码 2=参数/环境,3=ballast 安全中止,4=测量/解析失败

REC 字段

key单位含义
run—轮次,1..runs
size_mib / ballast_mibMiB申请大小 / 当前 ballast 总量(轻载=0)
mode—touch / memset
mmap_usµs建映射耗时(XNU 预留免费,与压力无关,用于交叉验证)
fill_msms申请耗时主体:touch=首触全部页;memset=整块写入
unit + unit_label—touch → ns/page(单页首触成本);memset → MiB/s(写入吞吐)
unmap_msmsmunmap 释放耗时
rss_mibMiB本轮峰值驻留(应为 size+页表开销)
faults次申请窗口内总缺页次数(mmap→fill→读回全程;Darwin 取 task_events_info,其余 getrusage);-1=平台不可用
majflt次其中需磁盘 I/O 的主缺页(匿名首触通常全为 0;出现非零说明已在换页)
pre_*MiB申请时刻前的系统内存快照(见下表)
post_*MiB申请驻留时快照:fill 完成后 mem_bench 保持驻留 3s(不计入耗时),驻留期采样;与 pre_* 同键集

pre_* / post_* 内存指标统一口径(同键集,平台映射)

统一 key含义Darwin (vm_stat)Linux (/proc/meminfo)
pre_total物理内存总量sysctl hw.memsizeMemTotal
pre_free空闲Pages freeMemFree
pre_avail可分配(含可回收)-1MemAvailable
pre_free_spec空闲+投机页Pages free + speculative-1
pre_file文件缓存File-backed pagesCached
pre_anon匿名驻留Anonymous pagesAnonPages
pre_swap_comp换出/已压缩数据量Pages stored in compressorSwapTotal − SwapFree
pre_comp_occ压缩器物理占用Pages occupied by compressor-1

不变量(消费方可以依赖)

消费示例

parse.py逐轮提取 耗时 + 申请前 free
import sys
for line in open(sys.argv[1]):
    if line.startswith("REC "):
        rec = dict(kv.split("=", 1) for kv in line.split()[1:])
        print(rec["run"], rec["fill_ms"], rec["pre_free"], rec["unit"], rec["unit_label"])
# 重载首触成本:
#   awk: grep '^REC' case-heavy-touch.txt | tr ' ' '\n' | grep -A0 '^unit='

从网页到对比表 —— 完整走一遍

核心逻辑:格式由 run_case.sh 约束,不依赖设备 —— 任何人在任何 iOS / Linux 机器上执行第②步, 得到的 .txt 都是同一 key=value 格式;对比 = 把任意两份 case 文件喂给 compare_cases.py(第一个文件自动作为基准)。文件可任意组合:轻 vs 重、 iOS vs Linux、改动前后、不同内核版本。

① 取件(用例全部材料,均可在本页"脚本源码"区下载)

材料来源去向
mem_stress.c / mem_bench.c / Makefile本页 · 脚本源码区编译(见环境准备),产物与脚本同目录
run_case.sh本页 · 脚本源码区(下载按钮)被测设备任意目录,chmod +x
compare_cases.py本页 · 脚本源码区(下载按钮)任意电脑(对比在采集侧做,不要求设备有 Python)

② 采集(被测设备上执行,生成四个 case 文件)

在被测设备上iOS 与 Linux 命令完全相同
sh ./run_case.sh -s 200M -m touch  -r 5          > case-light-touch.txt
sh ./run_case.sh -s 200M -m memset -r 5          > case-light-memset.txt
sh ./run_case.sh -s 200M -m touch  -r 5 -b 3600  > case-heavy-touch.txt
sh ./run_case.sh -s 200M -m memset -r 5 -b 3600  > case-heavy-memset.txt
# iOS 远程执行同一命令, 例:
#   ssh -p 2222 root@device 'cd /var/mobile/ios_memslice && sh ./run_case.sh -s 200M -m touch -r 5 -b 3600'
# 采集完把 .txt 拷回电脑 (scp / sftp), 或在设备上直接查看

③ 对比(电脑上执行)

compare_cases.py第一个文件 = 基准
# 同平台 轻载 vs 重载 (纯申请):
python3 compare_cases.py case-light-touch.txt case-heavy-touch.txt

# 同平台 轻载 vs 重载 (申请+写入):
python3 compare_cases.py case-light-memset.txt case-heavy-memset.txt

# 跨平台 同状态对比 (重命名区分平台后):
python3 compare_cases.py case-ios-light-touch.txt case-linux-light-touch.txt

④ 输出(以下为真实数据,非演示)

iOS · 轻载 vs 重载(touch,200M) —— 耗时表(含缺页) + pre/post 状态表 + 驻留开销表 + DELTA 汇总行:

compare-example-touch.txt 下载
COMPARE files=2 base=case-light-touch.txt size_mib=200 mode=touch

[耗时表]
file                          ballast runs  fill_ms avg/min/max                  unit  mmap_us unmap_ms   faults
----------------------------------------------------------------------------------------------------------------
case-light-touch.txt                0    5   36.42 /  35.25 /  37.62      2845.5 ns/page     12.8     10.5    12800
case-heavy-touch.txt             3600    5   40.46 /  37.81 /  42.56      3160.8 ns/page     12.2     14.1    12800

[pre_* 申请前快照] (每轮申请时刻前均值, MiB; N/A=平台无此指标)
指标             case-light-touch.txt  case-heavy-touch.txt         Δ
-------------------------------------------------------------------
total                        5735.0                5735.0     +0.0%
free                         3651.6                 277.8    -92.4%
avail                           N/A                   N/A         -
free_spec                    3890.8                 311.8    -92.0%
file                          710.4                 515.8    -27.4%
anon                          451.0                4049.2   +797.8%
swap_comp                     329.0                 325.8     -1.0%
comp_occ                      117.0                 113.0     -3.4%

[post_* 申请驻留时快照] (fill 后驻留期均值, MiB)
指标             case-light-touch.txt  case-heavy-touch.txt         Δ
-------------------------------------------------------------------
total                        5735.0                5735.0     +0.0%
free                         3462.4                  93.2    -97.3%
avail                           N/A                   N/A         -
free_spec                    3701.0                 113.0    -96.9%
file                          709.8                 501.6    -29.3%
anon                          651.2                4248.0   +552.3%
swap_comp                     329.0                 325.8     -1.0%
comp_occ                      117.0                 113.0     -3.4%

[驻留开销 post−pre] (申请 SIZE 对系统状态的净影响, MiB)
指标             case-light-touch.txt  case-heavy-touch.txt
---------------------------------------------------------
total                          +0.0                  +0.0
free                         -189.2                -184.6
avail                             -                     -
free_spec                    -189.8                -198.8
file                           -0.6                 -14.2
anon                         +200.2                +198.8
swap_comp                      +0.0                  +0.0
comp_occ                       +0.0                  +0.0

DELTA case-heavy-touch.txt         vs base: fill_ms=+11.1% unit=+11.1% unmap_ms=+34.2% faults=+0.0% pre_free=-92.4%

# 机器可读行 (key=value, 与用例记录同风格):
ROW file=case-light-touch.txt size_mib=200 mode=touch ballast_mib=0 runs=5 fill_ms_avg=36.423 fill_ms_min=35.252 fill_ms_max=37.617 unit_avg=2845.5 unit_label=ns/page mmap_us_avg=12.8 unmap_ms_avg=10.475 faults_avg=12800.0 majflt_avg=0.0 pre_total_avg=5735.0 pre_free_avg=3651.6 pre_avail_avg=-1 pre_free_spec_avg=3890.8 pre_file_avg=710.4 pre_anon_avg=451.0 pre_swap_comp_avg=329.0 pre_comp_occ_avg=117.0 post_total_avg=5735.0 post_free_avg=3462.4 post_avail_avg=-1 post_free_spec_avg=3701.0 post_file_avg=709.8 post_anon_avg=651.2 post_swap_comp_avg=329.0 post_comp_occ_avg=117.0
ROW file=case-heavy-touch.txt size_mib=200 mode=touch ballast_mib=3600 runs=5 fill_ms_avg=40.459 fill_ms_min=37.807 fill_ms_max=42.564 unit_avg=3160.8 unit_label=ns/page mmap_us_avg=12.2 unmap_ms_avg=14.060 faults_avg=12800.0 majflt_avg=0.0 pre_total_avg=5735.0 pre_free_avg=277.8 pre_avail_avg=-1 pre_free_spec_avg=311.8 pre_file_avg=515.8 pre_anon_avg=4049.2 pre_swap_comp_avg=325.8 pre_comp_occ_avg=113.0 post_total_avg=5735.0 post_free_avg=93.2 post_avail_avg=-1 post_free_spec_avg=113.0 post_file_avg=501.6 post_anon_avg=4248.0 post_swap_comp_avg=325.8 post_comp_occ_avg=113.0
DELTA file=case-heavy-touch.txt vs=case-light-touch.txt fill_ms_pct=+11.1% unit_pct=+11.1% unmap_ms_pct=+34.2% faults_pct=+0.0% pre_total_pct=+0.0% pre_free_pct=-92.4% pre_free_spec_pct=-92.0% pre_file_pct=-27.4% pre_anon_pct=+797.8% pre_swap_comp_pct=-1.0% pre_comp_occ_pct=-3.4% post_total_pct=+0.0% post_free_pct=-97.3% post_free_spec_pct=-96.9% post_file_pct=-29.3% post_anon_pct=+552.3% post_swap_comp_pct=-1.0% post_comp_occ_pct=-3.4%

跨平台 · iOS vs Linux(同为轻载 touch,200M):

compare-example-cross.txt 下载
COMPARE files=2 base=case-ios-light-touch.txt size_mib=200 mode=touch

[耗时表]
file                          ballast runs  fill_ms avg/min/max                  unit  mmap_us unmap_ms   faults
----------------------------------------------------------------------------------------------------------------
case-ios-light-touch.txt            0    5   36.42 /  35.25 /  37.62      2845.5 ns/page     12.8     10.5    12800
case-linux-light-touch.txt          0    5  210.46 / 166.24 / 282.39      4110.6 ns/page      7.4     32.4    51202

[pre_* 申请前快照] (每轮申请时刻前均值, MiB; N/A=平台无此指标)
指标             case-ios-light-touch.txt  case-linux-light-touch.txt         Δ
-----------------------------------------------------------------------------
total                            5735.0                      4895.0    -14.6%
free                             3651.6                      3050.8    -16.5%
avail                               N/A                      4326.6         -
free_spec                        3890.8                         N/A         -
file                              710.4                      1316.0    +85.2%
anon                              451.0                        89.0    -80.3%
swap_comp                         329.0                        50.0    -84.8%
comp_occ                          117.0                         N/A         -

[post_* 申请驻留时快照] (fill 后驻留期均值, MiB)
指标             case-ios-light-touch.txt  case-linux-light-touch.txt         Δ
-----------------------------------------------------------------------------
total                            5735.0                      4895.0    -14.6%
free                             3462.4                      2871.8    -17.1%
avail                               N/A                      4147.8         -
free_spec                        3701.0                         N/A         -
file                              709.8                      1316.0    +85.4%
anon                              651.2                       289.0    -55.6%
swap_comp                         329.0                        50.0    -84.8%
comp_occ                          117.0                         N/A         -

[驻留开销 post−pre] (申请 SIZE 对系统状态的净影响, MiB)
指标             case-ios-light-touch.txt  case-linux-light-touch.txt
-------------------------------------------------------------------
total                              +0.0                        +0.0
free                             -189.2                      -179.0
avail                                 -                      -178.8
free_spec                        -189.8                           -
file                               -0.6                        +0.0
anon                             +200.2                      +200.0
swap_comp                          +0.0                        +0.0
comp_occ                           +0.0                           -

DELTA case-linux-light-touch.txt   vs base: fill_ms=+477.8% unit=+44.5% unmap_ms=+209.8% faults=+300.0% pre_free=-16.5%

# 机器可读行 (key=value, 与用例记录同风格):
ROW file=case-ios-light-touch.txt size_mib=200 mode=touch ballast_mib=0 runs=5 fill_ms_avg=36.423 fill_ms_min=35.252 fill_ms_max=37.617 unit_avg=2845.5 unit_label=ns/page mmap_us_avg=12.8 unmap_ms_avg=10.475 faults_avg=12800.0 majflt_avg=0.0 pre_total_avg=5735.0 pre_free_avg=3651.6 pre_avail_avg=-1 pre_free_spec_avg=3890.8 pre_file_avg=710.4 pre_anon_avg=451.0 pre_swap_comp_avg=329.0 pre_comp_occ_avg=117.0 post_total_avg=5735.0 post_free_avg=3462.4 post_avail_avg=-1 post_free_spec_avg=3701.0 post_file_avg=709.8 post_anon_avg=651.2 post_swap_comp_avg=329.0 post_comp_occ_avg=117.0
ROW file=case-linux-light-touch.txt size_mib=200 mode=touch ballast_mib=0 runs=5 fill_ms_avg=210.465 fill_ms_min=166.240 fill_ms_max=282.386 unit_avg=4110.6 unit_label=ns/page mmap_us_avg=7.4 unmap_ms_avg=32.448 faults_avg=51202.0 majflt_avg=0.0 pre_total_avg=4895.0 pre_free_avg=3050.8 pre_avail_avg=4326.6 pre_free_spec_avg=-1 pre_file_avg=1316.0 pre_anon_avg=89.0 pre_swap_comp_avg=50.0 pre_comp_occ_avg=-1 post_total_avg=4895.0 post_free_avg=2871.8 post_avail_avg=4147.8 post_free_spec_avg=-1 post_file_avg=1316.0 post_anon_avg=289.0 post_swap_comp_avg=50.0 post_comp_occ_avg=-1
DELTA file=case-linux-light-touch.txt vs=case-ios-light-touch.txt fill_ms_pct=+477.8% unit_pct=+44.5% unmap_ms_pct=+209.8% faults_pct=+300.0% pre_total_pct=-14.6% pre_free_pct=-16.5% pre_file_pct=+85.2% pre_anon_pct=-80.3% pre_swap_comp_pct=-84.8% post_total_pct=-14.6% post_free_pct=-17.1% post_file_pct=+85.4% post_anon_pct=-55.6% post_swap_comp_pct=-84.8%

怎么读对比表

三平台真实输出(均为实测,非演示数据)

iOS — iPhone 12 Pro · iOS 14.8.1 · /bin/sh=dash · touch 64M ×2 · ballast 1200M
case-sample-ios.txt 下载
CASE ts=2026-10-09T17:14:55+0800 platform=Darwin kernel=Darwin-20.6.0 arch=iPhone13,3 size_mib=64 mode=touch runs=2 ballast_mib=1200 tool=mem_bench
PHASE name=case_start ts=2026-10-09T17:14:55+0800 pre_total=5735 pre_free=3926 pre_avail=-1 pre_free_spec=3932 pre_file=476 pre_anon=404 pre_swap_comp=338 pre_comp_occ=118
PHASE name=ballast_start ts=2026-10-09T17:14:55+0800 ballast_mib=1200 hold_s=900 pre_total=5735 pre_free=3926 pre_avail=-1 pre_free_spec=3932 pre_file=476 pre_anon=404 pre_swap_comp=338 pre_comp_occ=118
PHASE name=ballast_settled ts=2026-10-09T17:15:16+0800 waited_s=20 pid=16728 pre_total=5735 pre_free=2723 pre_avail=-1 pre_free_spec=2729 pre_file=476 pre_anon=1609 pre_swap_comp=338 pre_comp_occ=118
REC run=1 size_mib=64 mode=touch ballast_mib=1200 mmap_us=12.0 fill_ms=11.662 unit=2847.2 unit_label=ns/page unmap_ms=14.397 rss_mib=66.45 faults=4096 majflt=0 pre_total=5735 pre_free=2725 pre_avail=-1 pre_free_spec=2731 pre_file=476 pre_anon=1607 pre_swap_comp=338 pre_comp_occ=118 post_total=5735 post_free=2660 post_avail=-1 post_free_spec=2666 post_file=476 post_anon=1672 post_swap_comp=338 post_comp_occ=118
REC run=2 size_mib=64 mode=touch ballast_mib=1200 mmap_us=11.0 fill_ms=13.069 unit=3190.7 unit_label=ns/page unmap_ms=4.736 rss_mib=66.36 faults=4096 majflt=0 pre_total=5735 pre_free=2776 pre_avail=-1 pre_free_spec=2782 pre_file=477 pre_anon=1608 pre_swap_comp=338 pre_comp_occ=118 post_total=5735 post_free=2711 post_avail=-1 post_free_spec=2718 post_file=477 post_anon=1672 post_swap_comp=338 post_comp_occ=118
SUMMARY runs=2 fill_ms_avg=12.365 fill_ms_min=11.662 fill_ms_max=13.069
PHASE name=ballast_released ts=2026-10-09T17:15:23+0800 post_total=5735 post_free=3975 post_avail=-1 post_free_spec=3981 post_file=477 post_anon=409 post_swap_comp=338 post_comp_occ=118
Linux — Ubuntu · kernel 7.0.0 · aarch64 · touch 64M ×2 · ballast 2048M
case-sample-linux.txt 下载
CASE ts=2026-10-09T17:15:52+0800 platform=Linux kernel=Linux-7.0.0-34-generic arch=aarch64 size_mib=64 mode=touch runs=2 ballast_mib=2048 tool=mem_bench
PHASE name=case_start ts=2026-10-09T17:15:52+0800 pre_total=4895 pre_free=3108 pre_avail=4384 pre_free_spec=-1 pre_file=1316 pre_anon=90 pre_swap_comp=50 pre_comp_occ=-1
PHASE name=ballast_start ts=2026-10-09T17:15:52+0800 ballast_mib=2048 hold_s=900 pre_total=4895 pre_free=3108 pre_avail=4384 pre_free_spec=-1 pre_file=1316 pre_anon=90 pre_swap_comp=50 pre_comp_occ=-1
PHASE name=ballast_settled ts=2026-10-09T17:16:12+0800 waited_s=20 pid=163555 pre_total=4895 pre_free=1047 pre_avail=2323 pre_free_spec=-1 pre_file=1316 pre_anon=2137 pre_swap_comp=50 pre_comp_occ=-1
REC run=1 size_mib=64 mode=touch ballast_mib=2048 mmap_us=4.4 fill_ms=62.781 unit=3831.9 unit_label=ns/page unmap_ms=6.593 rss_mib=65.40 faults=16386 majflt=0 pre_total=4895 pre_free=1048 pre_avail=2324 pre_free_spec=-1 pre_file=1316 pre_anon=2137 pre_swap_comp=50 pre_comp_occ=-1 post_total=4895 post_free=990 post_avail=2266 post_free_spec=-1 post_file=1316 post_anon=2202 post_swap_comp=50 post_comp_occ=-1
REC run=2 size_mib=64 mode=touch ballast_mib=2048 mmap_us=30.6 fill_ms=32.351 unit=1974.5 unit_label=ns/page unmap_ms=6.777 rss_mib=65.40 faults=16386 majflt=0 pre_total=4895 pre_free=1024 pre_avail=2299 pre_free_spec=-1 pre_file=1316 pre_anon=2137 pre_swap_comp=50 pre_comp_occ=-1 post_total=4895 post_free=964 post_avail=2240 post_free_spec=-1 post_file=1316 post_anon=2201 post_swap_comp=50 post_comp_occ=-1
SUMMARY runs=2 fill_ms_avg=47.566 fill_ms_min=32.351 fill_ms_max=62.781
PHASE name=ballast_released ts=2026-10-09T17:16:19+0800 post_total=4895 post_free=3057 post_avail=4333 post_free_spec=-1 post_file=1316 post_anon=89 post_swap_comp=50 post_comp_occ=-1
macOS — Darwin 25.4 · arm64 · touch 64M ×2 · ballast 1024M
case-sample-macos.txt 下载
CASE ts=2026-10-09T17:15:24+0800 platform=Darwin kernel=Darwin-25.4.0 arch=arm64 size_mib=64 mode=touch runs=2 ballast_mib=1024 tool=mem_bench
PHASE name=case_start ts=2026-10-09T17:15:24+0800 pre_total=8192 pre_free=102 pre_avail=-1 pre_free_spec=181 pre_file=668 pre_anon=1119 pre_swap_comp=32190 pre_comp_occ=2679
PHASE name=ballast_start ts=2026-10-09T17:15:24+0800 ballast_mib=1024 hold_s=900 pre_total=8192 pre_free=102 pre_avail=-1 pre_free_spec=181 pre_file=668 pre_anon=1119 pre_swap_comp=32190 pre_comp_occ=2679
PHASE name=ballast_settled ts=2026-10-09T17:15:44+0800 waited_s=20 pid=94046 pre_total=8192 pre_free=66 pre_avail=-1 pre_free_spec=81 pre_file=633 pre_anon=1164 pre_swap_comp=33170 pre_comp_occ=2684
REC run=1 size_mib=64 mode=touch ballast_mib=1024 mmap_us=0.0 fill_ms=6.133 unit=1497.3 unit_label=ns/page unmap_ms=1.626 rss_mib=65.30 faults=4096 majflt=0 pre_total=8192 pre_free=63 pre_avail=-1 pre_free_spec=78 pre_file=633 pre_anon=1164 pre_swap_comp=33170 pre_comp_occ=2684 post_total=8192 post_free=80 post_avail=-1 post_free_spec=96 post_file=634 post_anon=1146 post_swap_comp=33261 post_comp_occ=2713
REC run=2 size_mib=64 mode=touch ballast_mib=1024 mmap_us=1.0 fill_ms=5.214 unit=1272.9 unit_label=ns/page unmap_ms=2.985 rss_mib=65.30 faults=4096 majflt=0 pre_total=8192 pre_free=74 pre_avail=-1 pre_free_spec=140 pre_file=674 pre_anon=1103 pre_swap_comp=33235 pre_comp_occ=2715 post_total=8192 post_free=60 post_avail=-1 post_free_spec=119 post_file=667 post_anon=1218 post_swap_comp=33182 post_comp_occ=2622
SUMMARY runs=2 fill_ms_avg=5.673 fill_ms_min=5.214 fill_ms_max=6.133
PHASE name=ballast_released ts=2026-10-09T17:15:51+0800 post_total=8192 post_free=699 post_avail=-1 post_free_spec=710 post_file=621 post_anon=1249 post_swap_comp=32064 post_comp_occ=2007
验证矩阵:iOS (iPhone13,3, dash, 设备端 ldid 签名) ✓ · Linux (Ubuntu aarch64, gcc 15.2) ✓ · macOS (bash 3.2 /bin/sh + zsh) ✓ —— 三平台的 ballast 生命周期、双模式解析、平台差异键(-1)均逐项核对通过。

脚本源码(用例全量归档)

用例涉及的 5 个文件全部在此,按用例数据流排列: run_case.sh(采集 harness)调用 mem_bench(测量工具)与 mem_stress(重载 ballast 工具), 由 Makefile 编译后两者,采集文件交给 compare_cases.py(对比工具)。本页自包含,无需跳转。

run_case.sh采集 harness · 纯 POSIX sh · 约 200 行 下载
#!/bin/sh
# run_case.sh — 轻重载"申请耗时"标准用例 harness (iOS / macOS / Linux 通用)
#
# 用法:
#   ./run_case.sh -s <N M> -m <touch|memset> -r <runs> [-b <ballast_mib>] [-w settle_s] [-t hold_s]
# 示例:
#   ./run_case.sh -s 200M -m touch  -r 5              # 轻载: 200M 纯申请 x 5 轮
#   ./run_case.sh -s 200M -m memset -r 5              # 轻载: 200M 申请+写入 x 5 轮
#   ./run_case.sh -s 200M -m touch  -r 5 -b 3600      # 重载: 自动建 3600MiB ballast, 测完自动释放
#
# 输出: 约束格式记录行 CASE/PHASE/REC/SUMMARY (key=value 令牌, 见 protocol.html)
#   REC = 耗时 (mmap_us/fill_ms/unmap_ms) + 缺页 (faults/majflt) + rss
#       + 申请前 (pre_*) 与申请驻留时 (post_*) 的内存统计
#   post_*: 每轮 fill 后 mem_bench 保持驻留 HOLD_FILL 秒, 驻留期采样
#
# 依赖: 同目录 mem_bench / mem_stress; 内存源 (Darwin: vm_stat+sysctl / Linux: /proc/meminfo)
# 约束: 纯 POSIX sh (dash/ash/bash/zsh), 不依赖 awk/bc/python — iOS 精简用户态可跑

SIZE=200M; MODE=touch; RUNS=5; BALLAST=0; SETTLE=20; HOLD=900
HOLD_FILL=3   # 每轮 fill 后驻留保持秒数 (post_* 采样窗口)
DIR=$(dirname "$0")
BENCH="$DIR/mem_bench"; STRESS="$DIR/mem_stress"
BPID=""; BCPID=""
TMPB=/tmp/.run_case.bench.$$

usage() { sed -n '3,15p' "$0"; exit 2; }
while getopts "s:m:r:b:w:t:h" opt 2>/dev/null; do
    case $opt in
        s) SIZE=$OPTARG ;; m) MODE=$OPTARG ;; r) RUNS=$OPTARG ;;
        b) BALLAST=$OPTARG ;; w) SETTLE=$OPTARG ;; t) HOLD=$OPTARG ;;
        h) usage ;; *) usage ;;
    esac
done

# ---- 参数校验 (size 仅支持整 MiB) ----
case $SIZE in ''|*[!0-9M]*) echo "ERROR code=bad_size size=$SIZE (仅整 MiB, 如 200M)"; exit 2 ;; esac
SIZE_MIB=${SIZE%M}
case $SIZE_MIB in ''|*[!0-9]*) echo "ERROR code=bad_size size=$SIZE"; exit 2 ;; esac
case $MODE in touch|memset) ;; *) echo "ERROR code=bad_mode mode=$MODE (touch|memset)"; exit 2 ;; esac
case $RUNS in ''|*[!0-9]*|0) echo "ERROR code=bad_runs runs=$RUNS"; exit 2 ;; esac
case $BALLAST in ''|*[!0-9]*) echo "ERROR code=bad_ballast ballast=$BALLAST"; exit 2 ;; esac
[ -x "$BENCH" ] || { echo "ERROR code=no_bench path=$BENCH"; exit 2; }
if [ "$BALLAST" -gt 0 ]; then [ -x "$STRESS" ] || { echo "ERROR code=no_stress path=$STRESS"; exit 2; }; fi

ts() { date +%Y-%m-%dT%H:%M:%S%z; }

# ---- 平台检测 ----
KERNEL=$(uname -s)
case $KERNEL in Darwin|Linux) ;; *) echo "ERROR code=unsupported_kernel kernel=$KERNEL"; exit 2 ;; esac
ARCH=$(uname -m)
PAGE_BYTES=0; TOTAL_MIB=-1

if [ "$KERNEL" = "Darwin" ]; then
    # vm_stat 首行固定为 "Mach Virtual Memory Statistics: (page size of NNNN bytes)"
    _hdr=$(vm_stat 2>/dev/null | { IFS= read -r _l; echo "$_l"; })
    PAGE_BYTES=0
    for _t in $_hdr; do
        case $_t in
            [0-9]*) PAGE_BYTES=$_t ;;
        esac
    done
    [ "$PAGE_BYTES" -gt 0 ] 2>/dev/null || PAGE_BYTES=16384
    _ms=$(sysctl -n hw.memsize 2>/dev/null) && TOTAL_MIB=$((_ms / 1048576))
fi

kib_pages_to_mib() { echo $(( $1 * PAGE_BYTES / 1048576 )); }

# ---- 统一内存快照 -> R_* (整 MiB, -1 = 平台无此指标) ----
snap_mem() {
    R_TOTAL=$TOTAL_MIB; R_AVAIL=-1; R_FREE_SPEC=-1; R_COMP_OCC=-1
    if [ "$KERNEL" = "Linux" ]; then
        R_FREE=-1; R_FILE=-1; R_ANON=-1; R_SWAP_COMP=-1
        [ -r /proc/meminfo ] || return 0
        _t=0 _f=0 _a=0 _c=0 _an=0 _st=0 _sf=0
        while IFS=' :' read -r k v rest; do
            case $k in
                MemTotal) _t=$v ;; MemFree) _f=$v ;; MemAvailable) _a=$v ;;
                Cached) _c=$v ;; AnonPages) _an=$v ;;
                SwapTotal) _st=$v ;; SwapFree) _sf=$v ;;
            esac
        done < /proc/meminfo
        R_TOTAL=$((_t / 1024)); R_FREE=$((_f / 1024)); R_AVAIL=$((_a / 1024))
        R_FILE=$((_c / 1024)); R_ANON=$((_an / 1024))
        R_SWAP_COMP=$(( (_st - _sf) / 1024 ))
    else
        vm_stat > /tmp/.run_case.$$ 2>/dev/null || { R_FREE=-1; R_FILE=-1; R_ANON=-1; R_SWAP_COMP=-1; return 0; }
        _pf=0 _psp=0 _pfb=0 _pan=0 _psc=0 _poc=0
        while IFS= read -r line; do
            case $line in
                "Pages free:"*)                   set -- $line; _pf=${3%.}  ;;
                "Pages speculative:"*)            set -- $line; _psp=${3%.} ;;
                "File-backed pages:"*)            set -- $line; _pfb=${3%.} ;;
                "Anonymous pages:"*)              set -- $line; _pan=${3%.} ;;
                "Pages stored in compressor:"*)   set -- $line; _psc=${5%.} ;;
                "Pages occupied by compressor:"*) set -- $line; _poc=${5%.} ;;
            esac
        done < /tmp/.run_case.$$
        rm -f /tmp/.run_case.$$
        R_FREE=$(kib_pages_to_mib $_pf)
        R_FREE_SPEC=$(kib_pages_to_mib $((_pf + _psp)))
        R_FILE=$(kib_pages_to_mib $_pfb)
        R_ANON=$(kib_pages_to_mib $_pan)
        R_SWAP_COMP=$(kib_pages_to_mib $_psc)
        R_COMP_OCC=$(kib_pages_to_mib $_poc)
    fi
}

mem_tokens() { # $1=前缀(pre/post)
    printf '%s_total=%s %s_free=%s %s_avail=%s %s_free_spec=%s %s_file=%s %s_anon=%s %s_swap_comp=%s %s_comp_occ=%s' \
        "$1" "$R_TOTAL" "$1" "$R_FREE" "$1" "$R_AVAIL" "$1" "$R_FREE_SPEC" \
        "$1" "$R_FILE" "$1" "$R_ANON" "$1" "$R_SWAP_COMP" "$1" "$R_COMP_OCC"
}

cleanup() {
    rc=$?
    trap - EXIT INT TERM
    if [ -n "$BCPID" ]; then
        kill "$BCPID" 2>/dev/null; wait "$BCPID" 2>/dev/null; BCPID=""
    fi
    if [ -n "$BPID" ]; then
        kill "$BPID" 2>/dev/null; wait "$BPID" 2>/dev/null; BPID=""
        snap_mem
        printf 'PHASE name=ballast_released ts=%s ' "$(ts)"; mem_tokens post; echo
    fi
    rm -f /tmp/.run_case.$$ "$TMPB"
    exit "$rc"
}
trap cleanup EXIT INT TERM

# 浮点(<=3位小数) -> 毫单位整数: "35.096"->35096, "12.0"->12000
to_milli() {
    _i=${1%%.*}; _f=${1#*.}
    [ "$_f" = "$1" ] && _f=""
    case $_f in
        "") _f=000 ;; ?) _f=${_f}00 ;; ??) _f=${_f}0 ;; ???) ;; *) _f=${_f%${_f#???}} ;;
    esac
    printf '%s%s' "$_i" "$_f"
}
fmt3() { printf '%d.%03d' $(($1 / 1000)) $(($1 % 1000)); }

# ---- 开始 ----
printf 'CASE ts=%s platform=%s kernel=%s arch=%s size_mib=%s mode=%s runs=%s ballast_mib=%s tool=mem_bench\n' \
    "$(ts)" "$KERNEL" "$KERNEL-$(uname -r)" "$ARCH" "$SIZE_MIB" "$MODE" "$RUNS" "$BALLAST"
snap_mem
printf 'PHASE name=case_start ts=%s ' "$(ts)"; mem_tokens pre; echo

# ---- 重载: 建 ballast (-P 50 半随机 ≈ 真实数据压缩比, 防 watchdog panic) ----
if [ "$BALLAST" -gt 0 ]; then
    printf 'PHASE name=ballast_start ts=%s ballast_mib=%s hold_s=%s ' "$(ts)" "$BALLAST" "$HOLD"; mem_tokens pre; echo
    nohup "$STRESS" "${BALLAST}M" -P 50 -q -t "$HOLD" >/dev/null 2>&1 &
    BPID=$!
    _waited=0
    while [ "$_waited" -lt "$SETTLE" ]; do
        sleep 2; _waited=$((_waited + 2))
        snap_mem
        if [ "$R_FREE" -lt 16 ]; then
            echo "PHASE name=ballast_abort ts=$(ts) reason=free_below_16MiB free_mib=$R_FREE"; exit 3
        fi
        kill -0 "$BPID" 2>/dev/null || { echo "PHASE name=ballast_abort ts=$(ts) reason=ballast_died"; exit 3; }
    done
    printf 'PHASE name=ballast_settled ts=%s waited_s=%s pid=%s ' "$(ts)" "$_waited" "$BPID"; mem_tokens pre; echo
fi

# ---- 测量循环: 每轮 pre 快照 -> 单轮 bench(fill 后驻留 HOLD_FILL 秒) -> 驻留期 post 快照 -> 解析配对 ----
_sum=0; _min=999999999; _max=0; _n=0
i=1
while [ "$i" -le "$RUNS" ]; do
    snap_mem
    pre_tok=$(mem_tokens pre)

    # bench 后台跑: fill(数十~数百 ms) 后保持驻留 3s; shell 在 ~1s 处采 post 快照
    "$BENCH" "$SIZE" -r 1 -m "$MODE" -H "$HOLD_FILL" >"$TMPB" 2>&1 &
    BCPID=$!
    sleep 1
    snap_mem
    post_tok=$(mem_tokens post)
    wait "$BCPID"; brc=$?
    BCPID=""
    if [ "$brc" -ne 0 ]; then
        echo "ERROR code=bench_failed run=$i rc=$brc"
        cat "$TMPB"
        exit 4
    fi
    out=$(cat "$TMPB")

    mmap_v=""; fill_v=""; unit_v=""; unit_l=""; unmap_v=""; rss_v=""; faults_v=""; majflt_v=""; found=0
    while IFS= read -r line; do
        case $line in
        "run 1/1:"*)
            found=1; _st=""
            set -- $line
            for t in "$@"; do
                case $_st in
                    mmap)  mmap_v=$t ;;
                    fill)  fill_v=$t ;;
                    unit)  unit_v=$t; _st=unit_l; continue ;;
                    unit_l) unit_l=${t%)}; _st="" ;;
                    unmap) unmap_v=$t ;;
                    rss)   rss_v=$t ;;
                esac
                case $t in
                    mmap=) _st=mmap ;;
                    ')=')  _st=fill ;;
                    'fill(memset)=') _st=fill ;;
                    '(')   _st=unit ;;
                    unmap=) _st=unmap ;;
                    rss=)  _st=rss ;;
                    faults=*)  faults_v=${t#faults=} ;;
                    majflt=*)  majflt_v=${t#majflt=} ;;
                    *) case $_st in mmap|fill|unmap|rss) _st="" ;; esac ;;
                esac
            done
            ;;
        esac
    done <<EOF
$out
EOF
    [ "$found" = 1 ] || { echo "ERROR code=parse_failed run=$i"; printf '%s\n' "$out"; exit 4; }
    [ -n "$faults_v" ] || faults_v=-1
    [ -n "$majflt_v" ] || majflt_v=-1

    printf 'REC run=%s size_mib=%s mode=%s ballast_mib=%s mmap_us=%s fill_ms=%s unit=%s unit_label=%s unmap_ms=%s rss_mib=%s faults=%s majflt=%s %s %s\n' \
        "$i" "$SIZE_MIB" "$MODE" "$BALLAST" "$mmap_v" "$fill_v" "$unit_v" "$unit_l" "$unmap_v" "$rss_v" "$faults_v" "$majflt_v" "$pre_tok" "$post_tok"

    _m=$(to_milli "$fill_v")
    _sum=$((_sum + _m)); _n=$((_n + 1))
    [ "$_m" -lt "$_min" ] && _min=$_m
    [ "$_m" -gt "$_max" ] && _max=$_m
    i=$((i + 1))
    [ "$i" -le "$RUNS" ] && sleep 1
done

if [ "$_n" -gt 0 ]; then
    printf 'SUMMARY runs=%s fill_ms_avg=%s fill_ms_min=%s fill_ms_max=%s\n' \
        "$_n" "$(fmt3 $((_sum / _n)))" "$(fmt3 $_min)" "$(fmt3 $_max)"
fi
mem_bench.c测量工具 · mmap/fill/unmap 耗时 · 439 行 下载
/*
 * mem_bench.c — 匿名页申请耗时基准 (iOS / HarmonyOS / macOS / Linux 通用)
 *
 * 功能:
 *   按入参大小反复 mmap 一块匿名私有内存, 分别统计:
 *     - mmap   耗时 (建立映射本身, 通常只有 µs 级)
 *     - fill   耗时 (memset 整块填充 —— 真正触发缺页 + 写入的主成本;
 *                     或 touch 模式: 每页写 1 字节, 专门测首次触页缺页成本)
 *     - unmap  耗时 (munmap 释放)
 *     - faults 缺页次数 (本轮申请窗口内的总缺页 + 需 I/O 的主缺页;
 *                       Darwin 用 task_events_info, 其余 getrusage)
 *   每轮结束后做轻量读回校验 (防止填充被优化掉, 并确认内存真实可读),
 *   最后输出 avg/min/max 汇总与吞吐率。
 *   -H <sec>: fill 之后、unmap 之前保持驻留 N 秒 —— 供外部 (run_case.sh)
 *   在驻留期间采集"申请后"的内存快照 (post_*); 保持期不计入任何耗时。
 *
 * 用法:
 *   mem_bench [-r n] [-m memset|touch|none] [-H sec] [-q] <size>[K|M|G|T]
 *
 * 构建:
 *   host      : cc -O2 -o mem_bench mem_bench.c
 *   iOS       : xcrun -sdk iphoneos clang -arch arm64 -O2 \
 *               -miphoneos-version-min=12.0 -o mem_bench mem_bench.c
 *   HarmonyOS : <OHOS_NDK>/llvm/bin/clang --target=aarch64-linux-ohos \
 *               --sysroot=<OHOS_NDK>/sysroot -O2 -o mem_bench mem_bench.c
 *
 * 说明:
 *   - 纯 POSIX C, 无第三方依赖; 仅 RSS 读取按平台分支。
 *   - 单位为二进制: K=1024, M=1024^2, G=1024^3, T=1024^4。
 *   - 每轮 memset 使用不同填充值 (0x11/0x22/...), 规避任何零页/去重优化。
 *   - iOS 为 16K 页, Linux/鸿蒙通常为 4K 页; touch 模式的 ns/page 指标
 *     可直接对比两平台的单缺页成本。
 */

#if !defined(__APPLE__)
#define _POSIX_C_SOURCE 200809L
#endif

#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/resource.h>
#include <time.h>
#include <unistd.h>

#if defined(__APPLE__)
#include <mach/mach.h>
#endif

#ifndef MAP_ANONYMOUS
#define MAP_ANONYMOUS MAP_ANON
#endif

enum fill_mode { FILL_MEMSET, FILL_TOUCH, FILL_NONE };

static volatile sig_atomic_t g_stop = 0;
static volatile uint64_t g_sink = 0;   /* 读回校验累加器, volatile 防优化 */
static size_t g_page = 4096;

/* ---------------- 公共小工具 ---------------- */

static void on_signal(int sig)
{
    (void)sig;
    g_stop = 1;
}

static double now_sec(void)
{
    struct timespec ts;
    clock_gettime(CLOCK_MONOTONIC, &ts);
    return (double)ts.tv_sec + (double)ts.tv_nsec * 1e-9;
}

static double to_mib(unsigned long long bytes)
{
    return (double)bytes / 1048576.0;
}

/* 解析大小参数 (与 mem_stress 相同: 二进制单位, 兼容 B/iB 后缀) */
static int parse_size(const char *s, unsigned long long *out)
{
    if (s == NULL || *s == '\0' || *s == '-' || *s == '+')
        return -1;

    errno = 0;
    char *end = NULL;
    unsigned long long v = strtoull(s, &end, 10);
    if (errno != 0 || end == s)
        return -1;

    const char *u = end;
    unsigned long long mult = 1ULL;

    if (*u == 'K' || *u == 'k' || *u == 'M' || *u == 'm' ||
        *u == 'G' || *u == 'g' || *u == 'T' || *u == 't') {
        switch (*u | 0x20) {
        case 'k': mult = 1ULL << 10; break;
        case 'm': mult = 1ULL << 20; break;
        case 'g': mult = 1ULL << 30; break;
        case 't': mult = 1ULL << 40; break;
        }
        u++;
        if (*u == 'i')
            u++;
        if (*u == 'B' || *u == 'b')
            u++;
    } else if (*u == 'B' || *u == 'b') {
        u++;
    }
    if (*u != '\0')
        return -1;
    if (v == 0)
        return -1;
    if (v > ULLONG_MAX / mult)
        return -1;

    *out = v * mult;
    return 0;
}

/* 当前驻留集 (字节); 取不到返回 0 (调用方按 0 跳过显示) */
static unsigned long long get_rss_bytes(void)
{
#if defined(__APPLE__)
    struct task_vm_info vm;
    mach_msg_type_number_t count = TASK_VM_INFO_COUNT;
    if (task_info(mach_task_self(), TASK_VM_INFO,
                  (task_info_t)&vm, &count) != KERN_SUCCESS)
        return 0;
    return (unsigned long long)vm.resident_size;
#else
    FILE *f = fopen("/proc/self/statm", "r");
    if (f == NULL)
        return 0;
    unsigned long long total = 0, resident = 0;
    int n = fscanf(f, "%llu %llu", &total, &resident);
    fclose(f);
    if (n != 2)
        return 0;
    return resident * (unsigned long long)g_page;
#endif
}

/* 峰值驻留集 (字节); Darwin 的 ru_maxrss 单位是字节, Linux 系是 KiB */
static unsigned long long get_peak_rss_bytes(void)
{
    struct rusage ru;
    if (getrusage(RUSAGE_SELF, &ru) != 0)
        return 0;
#if defined(__APPLE__)
    return (unsigned long long)ru.ru_maxrss;
#else
    return (unsigned long long)ru.ru_maxrss * 1024ULL;
#endif
}

/*
 * 当前累计缺页计数 (本进程)。
 * Darwin: task_events_info 的 faults=总缺页, pageins=需 I/O 的主缺页 (最可靠);
 * 其他平台: getrusage 的 ru_minflt/ru_majflt。
 * 取不到时 *ok=0 (调用方以 -1 表示不可用)。
 */
static void get_faults_now(unsigned long long *flt, unsigned long long *majflt,
                           int *ok)
{
#if defined(__APPLE__)
    struct task_events_info te;
    mach_msg_type_number_t cnt = TASK_EVENTS_INFO_COUNT;
    if (task_info(mach_task_self(), TASK_EVENTS_INFO,
                  (task_info_t)&te, &cnt) == KERN_SUCCESS) {
        *flt = (unsigned long long)te.faults;
        *majflt = (unsigned long long)te.pageins;
        *ok = 1;
        return;
    }
#endif
    struct rusage ru;
    if (getrusage(RUSAGE_SELF, &ru) == 0) {
        *flt = (unsigned long long)ru.ru_minflt + (unsigned long long)ru.ru_majflt;
        *majflt = (unsigned long long)ru.ru_majflt;
        *ok = 1;
        return;
    }
    *ok = 0;
}

/*
 * 严格的整数解析 (拒绝垃圾输入)。注: 不用 getopt —— BSD/musl 的 getopt
 * 不重排 argv, "size 在前、选项在后"的写法会解析失败; 手写解析保证
 * 各平台行为一致。
 */
static int parse_int(const char *s, long *out)
{
    if (s == NULL || *s == '\0')
        return -1;
    errno = 0;
    char *end = NULL;
    long v = strtol(s, &end, 10);
    if (errno != 0 || end == s || *end != '\0')
        return -1;
    *out = v;
    return 0;
}

static const char *fill_mode_name(enum fill_mode m)
{
    switch (m) {
    case FILL_MEMSET: return "memset";
    case FILL_TOUCH:  return "touch ";
    case FILL_NONE:   return "none  ";
    }
    return "?";
}

static void usage(FILE *out, const char *prog)
{
    fprintf(out,
        "mem_bench - anonymous mmap/memset timing benchmark (iOS/HarmonyOS/macOS/Linux)\n"
        "\n"
        "usage: %s [-r n] [-m mode] [-H sec] [-q] <size>\n"
        "\n"
        "  <size>    bytes of anonymous memory per run\n"
        "            e.g. 268435456 | 100K | 512M | 2G (binary units, B/iB suffix ok)\n"
        "  -r n      repeat runs (default 3)\n"
        "  -m mode   fill mode after mmap (default memset):\n"
        "              memset  memset the whole region (faults + bandwidth)\n"
        "              touch   write 1 byte per page (first-touch fault cost, ns/page)\n"
        "              none    mmap only (mapping setup/teardown cost)\n"
        "  -H sec    hold mapping resident N sec between fill and unmap\n"
        "            (for external post-allocation snapshots; not timed)\n"
        "  -q        quiet: per-run lines suppressed\n"
        "\n"
        "per-run line also reports faults=<total> majflt=<io> (page faults in\n"
        "the allocation window; -1 = unavailable on this platform).\n"
        "\n"
        "examples:\n"
        "  %s 512M -r 5          time mmap + memset of 512M, 5 runs\n"
        "  %s 512M -m touch      time first-touch page faults (ns/page)\n"
        "  %s 512M -H 3          hold 3s after fill for external snapshot\n",
        prog, prog, prog, prog);
}

/* 汇总打印一行: name avg/min/max (value 数组单位为秒, 乘 scale 换显示单位) */
static void print_stats(const char *name, const double *v, int n,
                        double scale, const char *unit)
{
    double sum = 0.0, mn = v[0], mx = v[0];
    for (int i = 0; i < n; i++) {
        sum += v[i];
        if (v[i] < mn) mn = v[i];
        if (v[i] > mx) mx = v[i];
    }
    printf("%-7s: avg %10.3f %s | min %10.3f %s | max %10.3f %s\n",
           name, sum / (double)n * scale, unit,
           mn * scale, unit, mx * scale, unit);
}

int main(int argc, char **argv)
{
    int repeats = 3;
    int quiet = 0;
    long hold_s = 0;
    enum fill_mode mode = FILL_MEMSET;
    const char *size_arg = NULL;

    for (int i = 1; i < argc; i++) {
        const char *a = argv[i];
        if (strcmp(a, "-q") == 0) {
            quiet = 1;
        } else if (strcmp(a, "-h") == 0 || strcmp(a, "--help") == 0) {
            usage(stdout, argv[0]);
            return 0;
        } else if (strcmp(a, "-H") == 0) {
            long v = 0;
            if (i + 1 >= argc || parse_int(argv[i + 1], &v) != 0 ||
                v < 0 || v > 3600) {
                fprintf(stderr, "error: -H expects seconds in 0..3600\n");
                return 2;
            }
            i++;
            hold_s = v;
        } else if (strcmp(a, "-r") == 0) {
            long v = 0;
            if (i + 1 >= argc || parse_int(argv[i + 1], &v) != 0 ||
                v < 1 || v > 10000) {
                fprintf(stderr, "error: -r expects an integer in 1..10000\n");
                return 2;
            }
            i++;
            repeats = (int)v;
        } else if (strcmp(a, "-m") == 0) {
            if (i + 1 >= argc) {
                fprintf(stderr, "error: -m expects a mode (memset|touch|none)\n");
                return 2;
            }
            i++;
            if (strcmp(argv[i], "memset") == 0)      mode = FILL_MEMSET;
            else if (strcmp(argv[i], "touch") == 0)  mode = FILL_TOUCH;
            else if (strcmp(argv[i], "none") == 0)   mode = FILL_NONE;
            else {
                fprintf(stderr, "error: unknown mode '%s' (memset|touch|none)\n",
                        argv[i]);
                return 2;
            }
        } else if (a[0] == '-' && a[1] != '\0') {
            fprintf(stderr, "error: unknown option '%s'\n", a);
            usage(stderr, argv[0]);
            return 2;
        } else {
            if (size_arg != NULL) {
                fprintf(stderr, "error: multiple sizes given ('%s' and '%s')\n",
                        size_arg, a);
                return 2;
            }
            size_arg = a;
        }
    }
    if (size_arg == NULL) {
        usage(stderr, argv[0]);
        return 2;
    }

    unsigned long long req = 0;
    if (parse_size(size_arg, &req) != 0) {
        fprintf(stderr, "error: bad size '%s' (try 512M / 2G / 65536K)\n",
                size_arg);
        return 2;
    }

    long ps = sysconf(_SC_PAGESIZE);
    if (ps > 0)
        g_page = (size_t)ps;

    if (req > (unsigned long long)(SIZE_MAX - (g_page - 1))) {
        fprintf(stderr, "error: size %llu bytes exceeds this platform's address space\n",
                req);
        return 2;
    }
    size_t size = ((size_t)req + g_page - 1) & ~((size_t)g_page - 1);
    unsigned long long pages = (unsigned long long)(size / g_page);

    setvbuf(stdout, NULL, _IOLBF, 0);

    struct sigaction sa;
    memset(&sa, 0, sizeof sa);
    sa.sa_handler = on_signal;
    sigemptyset(&sa.sa_mask);
    sa.sa_flags = 0;
    sigaction(SIGINT, &sa, NULL);
    sigaction(SIGTERM, &sa, NULL);

    double *t_mmap = malloc((size_t)repeats * sizeof(double));
    double *t_fill = malloc((size_t)repeats * sizeof(double));
    double *t_unmap = malloc((size_t)repeats * sizeof(double));
    if (t_mmap == NULL || t_fill == NULL || t_unmap == NULL) {
        fprintf(stderr, "error: out of memory\n");
        return 1;
    }

    printf("target : %llu bytes (%.2f MiB), %llu page(s) x %zu B, "
           "mode=%s, runs=%d\n",
           (unsigned long long)size, to_mib(size), pages, g_page,
           fill_mode_name(mode), repeats);

    int completed = 0;
    for (int i = 0; i < repeats && !g_stop; i++) {
        /* --- 申请窗口缺页计数: 起点采样 --- */
        unsigned long long f0 = 0, f0m = 0;
        int fok0 = 0;
        get_faults_now(&f0, &f0m, &fok0);

        /* --- mmap --- */
        double t0 = now_sec();
        char *p = mmap(NULL, size, PROT_READ | PROT_WRITE,
                       MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
        double t1 = now_sec();
        if (p == MAP_FAILED) {
            fprintf(stderr, "error: mmap %llu bytes failed on run %d: %s\n",
                    (unsigned long long)size, i + 1, strerror(errno));
#if defined(__APPLE__)
            fprintf(stderr, "hint: iOS caps a single process's anonymous "
                            "reservation (~4GiB observed on 14.8); "
                            "try a smaller size.\n");
#endif
            break;
        }
        t_mmap[i] = t1 - t0;

        /* --- fill --- */
        unsigned char pat = (unsigned char)(0x11 * (unsigned)(i + 1)); /* 0x11,0x22,... */
        t0 = now_sec();
        if (mode == FILL_MEMSET) {
            memset(p, pat, size);
        } else if (mode == FILL_TOUCH) {
            for (size_t off = 0; off < size && !g_stop; off += g_page)
                p[off] = (char)pat;
        }
        t1 = now_sec();
        t_fill[i] = t1 - t0;

        /* 轻量读回校验: 每页读首字节累加, 防止填充/映射被优化掉 */
        if (mode != FILL_NONE) {
            uint64_t sum = 0;
            for (size_t off = 0; off < size; off += g_page)
                sum += (uint64_t)(unsigned char)p[off];
            g_sink = sum;
        }
        unsigned long long rss = get_rss_bytes();

        /* --- 申请窗口缺页计数: 终点采样 (fill+读回全部计入) --- */
        unsigned long long f1 = 0, f1m = 0;
        int fok1 = 0;
        get_faults_now(&f1, &f1m, &fok1);
        long long flt = -1, flt_maj = -1;
        if (fok0 && fok1) {
            flt = (long long)(f1 - f0);
            flt_maj = (long long)(f1m - f0m);
        }

        /* --- 驻留保持 (供外部采"申请后"快照; 不计入任何耗时) --- */
        if (hold_s > 0 && !g_stop) {
            struct timespec hts = { hold_s, 0 };
            nanosleep(&hts, NULL);
        }

        /* --- unmap --- */
        t0 = now_sec();
        munmap(p, size);
        t_unmap[i] = now_sec() - t0;

        completed = i + 1;
        if (!quiet) {
            printf("run %d/%d: mmap=%9.1f us | fill(%s)=%10.3f ms",
                   i + 1, repeats, t_mmap[i] * 1e6,
                   mode == FILL_MEMSET ? "memset" :
                   mode == FILL_TOUCH  ? "touch " : "none  ",
                   t_fill[i] * 1e3);
            if (mode == FILL_MEMSET && t_fill[i] > 0.0)
                printf(" (%8.1f MiB/s)", to_mib(size) / t_fill[i]);
            if (mode == FILL_TOUCH && t_fill[i] > 0.0 && pages > 0)
                printf(" (%8.1f ns/page)",
                       t_fill[i] * 1e9 / (double)pages);
            printf(" | unmap=%8.3f ms", t_unmap[i] * 1e3);
            if (rss)
                printf(" | rss=%8.2f MiB", to_mib(rss));
            printf(" | faults=%lld majflt=%lld", flt, flt_maj);
            if (hold_s > 0)
                printf(" | held=%lds", hold_s);
            printf("\n");
        }

        if (i + 1 < repeats) {
            struct timespec ts = { 0, 100 * 1000 * 1000 };  /* 100ms 间隔 */
            nanosleep(&ts, NULL);
        }
    }

    if (completed == 0) {
        fprintf(stderr, "error: no run completed\n");
        free(t_mmap); free(t_fill); free(t_unmap);
        return 1;
    }

    /* ---- 汇总 ---- */
    printf("---- summary (%d run%s, %.2f MiB, %s mode) ----\n",
           completed, completed == 1 ? "" : "s", to_mib(size),
           mode == FILL_MEMSET ? "memset" :
           mode == FILL_TOUCH  ? "touch"  : "none");
    print_stats("mmap", t_mmap, completed, 1e6, "us");
    if (mode != FILL_NONE)
        print_stats("fill", t_fill, completed, 1e3, "ms");
    print_stats("unmap", t_unmap, completed, 1e3, "ms");

    if (mode == FILL_MEMSET) {
        double tp_sum = 0.0;
        int tp_n = 0;
        for (int i = 0; i < completed; i++) {
            if (t_fill[i] > 0.0) {
                tp_sum += to_mib(size) / t_fill[i];
                tp_n++;
            }
        }
        if (tp_n > 0)
            printf("memset throughput: avg %.1f MiB/s over %d run(s)\n",
                   tp_sum / (double)tp_n, tp_n);
    }
    if (mode == FILL_TOUCH && pages > 0) {
        double fp_sum = 0.0;
        int fp_n = 0;
        for (int i = 0; i < completed; i++) {
            if (t_fill[i] > 0.0) {
                fp_sum += t_fill[i] * 1e9 / (double)pages;
                fp_n++;
            }
        }
        if (fp_n > 0)
            printf("first-touch fault: avg %.1f ns/page over %d run(s)\n",
                   fp_sum / (double)fp_n, fp_n);
    }

    printf("peak rss: %.2f MiB\n", to_mib(get_peak_rss_bytes()));
    (void)g_sink;
    free(t_mmap); free(t_fill); free(t_unmap);
    return 0;
}
mem_stress.c重载 ballast 工具 · -P 50 填充 · 497 行 下载
/*
 * mem_stress.c — 匿名页内存加压工具 (iOS / HarmonyOS / macOS / Linux 通用)
 *
 * 功能:
 *   按入参大小 mmap 一块匿名私有内存 (MAP_PRIVATE|MAP_ANONYMOUS), 并逐页写入
 *   触页 (touch) 提交物理页, 形成真实内存压力; 之后按参数保持一段时间
 *   (或直到收到 SIGINT/SIGTERM) 再释放。
 *
 *   可选 -k 周期性重触: 每个周期向所有页写入新值, 迫使被 XNU compressor /
 *   Linux zram 压缩回收的页重新解压驻留, 并把干净页重新弄脏, 维持压力。
 *
 * 用法:
 *   mem_stress [-f|-R] [-k sec] [-t sec] [-qv] <size>[K|M|G|T]
 *     -R = 随机字节填充 (不可压缩, 模拟真实负载; 默认触页/0xA5 模式会被
 *          compressor 几乎零成本吸收, 无法形成持续压力)
 *
 * 构建:
 *   host      : cc -O2 -o mem_stress mem_stress.c
 *   iOS       : xcrun -sdk iphoneos clang -arch arm64 -O2 \
 *               -miphoneos-version-min=12.0 -o mem_stress mem_stress.c
 *   HarmonyOS : <OHOS_NDK>/llvm/bin/clang --target=aarch64-linux-ohos \
 *               --sysroot=<OHOS_NDK>/sysroot -O2 -o mem_stress mem_stress.c
 *
 * 说明:
 *   - 纯 POSIX C, 无第三方依赖; 仅 RSS/footprint 读取按平台分支。
 *   - 单位为二进制: K=1024, M=1024^2, G=1024^3, T=1024^4。
 *   - iOS 上单进程匿名保留有 ~4GiB 上限 (14.8 实测), 超限 mmap 直接失败;
 *     更常见的是压力过大先被 jetsam 以 SIGKILL 终止 —— 属预期行为。
 */

#if !defined(__APPLE__)
#define _POSIX_C_SOURCE 200809L
#endif

#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/resource.h>
#include <time.h>
#include <unistd.h>

#if defined(__APPLE__)
#include <mach/mach.h>
#endif

#ifndef MAP_ANONYMOUS
#define MAP_ANONYMOUS MAP_ANON
#endif

static volatile sig_atomic_t g_stop = 0;
static size_t g_page = 4096;

/* ---------------- 公共小工具 ---------------- */

static void on_signal(int sig)
{
    (void)sig;
    g_stop = 1;
}

static double now_sec(void)
{
    struct timespec ts;
    clock_gettime(CLOCK_MONOTONIC, &ts);
    return (double)ts.tv_sec + (double)ts.tv_nsec * 1e-9;
}

static double to_mib(unsigned long long bytes)
{
    return (double)bytes / 1048576.0;
}

/*
 * 解析大小参数: "1024" "100K" "512M" "2G" "1T", 兼容 B/iB 后缀与大小写。
 * 二进制单位 (K=1024)。成功返回 0, 失败返回 -1。
 */
static int parse_size(const char *s, unsigned long long *out)
{
    if (s == NULL || *s == '\0' || *s == '-' || *s == '+')
        return -1;

    errno = 0;
    char *end = NULL;
    unsigned long long v = strtoull(s, &end, 10);
    if (errno != 0 || end == s)
        return -1;

    const char *u = end;
    unsigned long long mult = 1ULL;

    if (*u == 'K' || *u == 'k' || *u == 'M' || *u == 'm' ||
        *u == 'G' || *u == 'g' || *u == 'T' || *u == 't') {
        switch (*u | 0x20) {
        case 'k': mult = 1ULL << 10; break;
        case 'm': mult = 1ULL << 20; break;
        case 'g': mult = 1ULL << 30; break;
        case 't': mult = 1ULL << 40; break;
        }
        u++;
        if (*u == 'i')                 /* KiB / MiB / GiB ... */
            u++;
        if (*u == 'B' || *u == 'b')
            u++;
    } else if (*u == 'B' || *u == 'b') {
        u++;                           /* "100B" = 100 字节 */
    }
    if (*u != '\0')
        return -1;
    if (v == 0)
        return -1;
    if (v > ULLONG_MAX / mult)
        return -1;

    *out = v * mult;
    return 0;
}

/* 当前驻留集 (字节); 取不到返回 0 (调用方按 0 跳过显示) */
static unsigned long long get_rss_bytes(void)
{
#if defined(__APPLE__)
    struct task_vm_info vm;
    mach_msg_type_number_t count = TASK_VM_INFO_COUNT;
    if (task_info(mach_task_self(), TASK_VM_INFO,
                  (task_info_t)&vm, &count) != KERN_SUCCESS)
        return 0;
    return (unsigned long long)vm.resident_size;
#else
    /* Linux / OpenHarmony(musl): /proc/self/statm 第二列 = 驻留页数 */
    FILE *f = fopen("/proc/self/statm", "r");
    if (f == NULL)
        return 0;
    unsigned long long total = 0, resident = 0;
    int n = fscanf(f, "%llu %llu", &total, &resident);
    fclose(f);
    if (n != 2)
        return 0;
    return resident * (unsigned long long)g_page;
#endif
}

#if defined(__APPLE__)
/* iOS jetsam 的判定口径: phys_footprint = 驻留脏页 + 已压缩脏页 + IOKit 映射 */
static unsigned long long get_footprint_bytes(void)
{
    struct task_vm_info vm;
    mach_msg_type_number_t count = TASK_VM_INFO_COUNT;
    if (task_info(mach_task_self(), TASK_VM_INFO,
                  (task_info_t)&vm, &count) != KERN_SUCCESS)
        return 0;
    return (unsigned long long)vm.phys_footprint;
}
#endif

/* 峰值驻留集 (字节); Darwin 的 ru_maxrss 单位是字节, Linux 系是 KiB */
static unsigned long long get_peak_rss_bytes(void)
{
    struct rusage ru;
    if (getrusage(RUSAGE_SELF, &ru) != 0)
        return 0;
#if defined(__APPLE__)
    return (unsigned long long)ru.ru_maxrss;
#else
    return (unsigned long long)ru.ru_maxrss * 1024ULL;
#endif
}

/* xorshift64* 伪随机数: 填充不可压缩 ballast (随机数据 WKdm 压不动,
 * 与 0xA5 模式填充不同, 无法被 compressor 几乎零成本地吸收) */
static uint64_t g_prng = 0;

static void prng_seed(uint64_t s)
{
    g_prng = s ? s : 0x9E3779B97F4A7C15ULL;
}

static uint64_t prng_next(void)
{
    uint64_t x = g_prng;
    x ^= x << 13;
    x ^= x >> 7;
    x ^= x << 17;
    g_prng = x;
    return x * 0x2545F4914F6CDD1DULL;
}

/* 整块填充随机字节, 密度 pct (1..100): 每页前 pct% 为随机字节, 其余清零。
 * pct=100 即全随机 (WKdm ~1:1, compressor 无净收益); pct=50 约 2:1 ——
 * 接近真实 App 数据的压缩比, 可形成"压缩器仍有回收余量"的可持续重载。 */
static void fill_random(char *buf, size_t size, unsigned cycle, int pct)
{
    prng_seed(0x9E3779B97F4A7C15ULL * (uint64_t)(cycle + 1) ^
              (uint64_t)time(NULL) ^ (uint64_t)(uintptr_t)buf);
    if (pct >= 100) {
        size_t n64 = size / 8;
        uint64_t *q = (uint64_t *)(void *)buf;   /* mmap 区页对齐, 安全 */
        for (size_t i = 0; i < n64; i++)
            q[i] = prng_next();
        for (size_t i = n64 * 8; i < size; i++)
            buf[i] = (char)prng_next();
        return;
    }
    /* 部分密度: 每页 [0, rand_bytes) 随机, 其余 0 */
    size_t rand_bytes = (size_t)((unsigned long long)g_page * (unsigned)pct / 100);
    if (rand_bytes == 0)
        rand_bytes = 1;
    memset(buf, 0, size);
    for (size_t off = 0; off < size; off += g_page) {
        size_t remain = rand_bytes;
        if (off + remain > size)
            remain = size - off;
        size_t n64 = remain / 8;
        uint64_t *q = (uint64_t *)(void *)(buf + off);
        for (size_t i = 0; i < n64; i++)
            q[i] = prng_next();
        for (size_t i = n64 * 8; i < remain; i++)
            buf[off + i] = (char)prng_next();
    }
}

/*
 * 解析秒数参数 (strtod 严格校验, 拒绝垃圾输入)。成功返回 0。
 * 注: 不用 getopt —— BSD/musl 的 getopt 不重排 argv, "size 在前、选项在后"
 * 的写法会解析失败; 手写解析保证各平台行为一致。
 */
static int parse_seconds(const char *s, double *out)
{
    if (s == NULL || *s == '\0')
        return -1;
    errno = 0;
    char *end = NULL;
    double v = strtod(s, &end);
    if (errno != 0 || end == s || *end != '\0' || v < 0.0)
        return -1;
    *out = v;
    return 0;
}

static void usage(FILE *out, const char *prog)
{
    fprintf(out,
        "mem_stress - anonymous memory pressure tool (iOS/HarmonyOS/macOS/Linux)\n"
        "\n"
        "usage: %s [-f] [-k sec] [-t sec] [-qv] <size>\n"
        "\n"
        "  <size>    bytes of anonymous memory to commit\n"
        "            e.g. 268435456 | 100K | 512M | 1500M | 2G | 1T\n"
        "            (binary units: K=1024, M=1024^2, G=1024^3; B/iB suffix ok)\n"
        "  -f        full fill: memset the whole region (default: 1 byte per page)\n"
        "  -R        fill with pseudo-random bytes: incompressible ballast that\n"
        "            the compressor cannot absorb (realistic heavy load)\n"
        "  -P n      partial random fill: first n%% of each page random, rest zero\n"
        "            (n=50 approximates real app data, ~2:1 WKdm ratio)\n"
        "  -k sec    re-touch all pages every <sec> while holding, to defeat\n"
        "            compressor/zram reclaim (0 = off, default off)\n"
        "  -t sec    hold duration after touch, then release\n"
        "            (default: hold until SIGINT/SIGTERM)\n"
        "  -q        quiet (suppress progress lines)\n"
        "  -v        verbose progress\n"
        "\n"
        "examples:\n"
        "  %s 512M -t 30              commit 512M, hold 30s, release\n"
        "  %s 1500M -t 60 -k 5        hold 60s, re-touch every 5s against compression\n"
        "  %s 2000M -R -t 900          incompressible ballast (heavy load emulation)\n",
        prog, prog, prog, prog);
}

int main(int argc, char **argv)
{
    int full_fill = 0, random_fill = 0, random_pct = 0, verbose = 0, quiet = 0;
    double keep_interval = 0.0;
    double hold_secs = -1.0;           /* -1 = 一直持有直到信号 */
    const char *size_arg = NULL;

    for (int i = 1; i < argc; i++) {
        const char *a = argv[i];
        if (strcmp(a, "-f") == 0) {
            full_fill = 1;
        } else if (strcmp(a, "-R") == 0) {
            random_fill = 1;
            random_pct = 100;
        } else if (strcmp(a, "-P") == 0) {
            if (i + 1 >= argc) {
                fprintf(stderr, "error: -P expects a percentage 1..100\n");
                return 2;
            }
            i++;
            long v = strtol(argv[i], NULL, 10);
            if (v < 1 || v > 100 || argv[i][0] == '\0' ||
                (strchr(argv[i], '-') != NULL)) {
                fprintf(stderr, "error: -P expects a percentage 1..100\n");
                return 2;
            }
            random_fill = 1;
            random_pct = (int)v;
        } else if (strcmp(a, "-q") == 0) {
            quiet = 1;
        } else if (strcmp(a, "-v") == 0) {
            verbose = 1;
        } else if (strcmp(a, "-h") == 0 || strcmp(a, "--help") == 0) {
            usage(stdout, argv[0]);
            return 0;
        } else if (strcmp(a, "-k") == 0 || strcmp(a, "-t") == 0) {
            double v = 0.0;
            if (i + 1 >= argc || parse_seconds(argv[i + 1], &v) != 0) {
                fprintf(stderr, "error: %s expects a non-negative number of seconds\n", a);
                return 2;
            }
            i++;
            if (a[1] == 'k')
                keep_interval = v;
            else
                hold_secs = v;
        } else if (a[0] == '-' && a[1] != '\0') {
            fprintf(stderr, "error: unknown option '%s'\n", a);
            usage(stderr, argv[0]);
            return 2;
        } else {
            if (size_arg != NULL) {
                fprintf(stderr, "error: multiple sizes given ('%s' and '%s')\n",
                        size_arg, a);
                return 2;
            }
            size_arg = a;
        }
    }
    if (size_arg == NULL) {
        usage(stderr, argv[0]);
        return 2;
    }

    unsigned long long req = 0;
    if (parse_size(size_arg, &req) != 0) {
        fprintf(stderr, "error: bad size '%s' (try 512M / 2G / 65536K)\n",
                size_arg);
        return 2;
    }

    long ps = sysconf(_SC_PAGESIZE);
    if (ps > 0)
        g_page = (size_t)ps;

    if (req > (unsigned long long)(SIZE_MAX - (g_page - 1))) {
        fprintf(stderr, "error: size %llu bytes exceeds this platform's address space\n",
                req);
        return 2;
    }
    size_t size = ((size_t)req + g_page - 1) & ~((size_t)g_page - 1);
    unsigned long long pages = (unsigned long long)(size / g_page);

    setvbuf(stdout, NULL, _IOLBF, 0);  /* 管道/ssh 下进度实时可见 */

    struct sigaction sa;
    memset(&sa, 0, sizeof sa);
    sa.sa_handler = on_signal;
    sigemptyset(&sa.sa_mask);
    sa.sa_flags = 0;                   /* 不重启: nanosleep 被信号打断立刻返回 */
    sigaction(SIGINT, &sa, NULL);
    sigaction(SIGTERM, &sa, NULL);

    double t_start = now_sec();

    /* ---- 申请匿名区 ---- */
    double t0 = now_sec();
    char *mem = mmap(NULL, size, PROT_READ | PROT_WRITE,
                     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
    double map_s = now_sec() - t0;
    if (mem == MAP_FAILED) {
        fprintf(stderr, "error: mmap %llu bytes failed: %s\n",
                (unsigned long long)size, strerror(errno));
#if defined(__APPLE__)
        fprintf(stderr, "hint: iOS caps a single process's anonymous reservation "
                        "(~4GiB observed on 14.8); try a smaller size.\n");
#endif
        return 1;
    }

    if (!quiet)
        printf("alloc  : %llu bytes (%.2f MiB), %llu page(s) x %zu B, "
               "mmap %.3f ms\n",
               (unsigned long long)size, to_mib(size), pages, g_page,
               map_s * 1e3);

    /* ---- 触页提交物理内存 ---- */
    unsigned long long done = 0;       /* 已触页数 (page-touch 模式) */
    t0 = now_sec();
    if (random_fill) {
        fill_random(mem, size, 0, random_pct);   /* 密度见 -P/-R */
    } else if (full_fill) {
        memset(mem, 0xA5, size);       /* 整块填充 (不可中途打断) */
    } else {
        /* 每页首字节写一次即触发缺页提交; 默认每 10% 汇报, -v 每 1% */
        unsigned long long report_every = pages / (verbose ? 100 : 10);
        if (report_every == 0)
            report_every = 1;
        for (size_t off = 0; off < size; off += g_page) {
            if (g_stop)
                break;
            mem[off] = (char)0xA5;
            done++;
            if (!quiet && (done % report_every) == 0)
                printf("touch  : %3llu%% (%8.2f MiB) elapsed %.2f s\n",
                       done * 100ULL / pages,
                       to_mib(done * (unsigned long long)g_page),
                       now_sec() - t0);
        }
    }
    double touch_s = now_sec() - t0;

    if (g_stop && !full_fill && !random_fill) {
        printf("touch  : interrupted at %.2f MiB (%llu/%llu pages)\n",
               to_mib(done * (unsigned long long)g_page), done, pages);
    } else {
        printf("touch  : %s %llu pages (%.2f MiB) in %.3f s",
               (random_fill || full_fill) ? "filled" : "touched",
               pages, to_mib(size), touch_s);
        if (random_fill)
            printf(" [random %d%%/page]", random_pct);
        if (touch_s > 0.0)
            printf(" [%.1f MiB/s, %.1fK pages/s]",
                   to_mib(size) / touch_s,
                   (double)pages / touch_s / 1000.0);
        printf("\n");
    }

    {
        unsigned long long rss = get_rss_bytes();
#if defined(__APPLE__)
        unsigned long long fp = get_footprint_bytes();
        if (rss || fp)
            printf("rss    : resident %.2f MiB, phys_footprint %.2f MiB\n",
                   to_mib(rss), to_mib(fp));
#else
        if (rss)
            printf("rss    : resident %.2f MiB\n", to_mib(rss));
#endif
    }

    /* ---- 保持 (可选周期重触) ---- */
    if (!g_stop) {
        if (hold_secs >= 0.0) {
            if (!quiet)
                printf("hold   : %.3f s%s\n", hold_secs,
                       keep_interval > 0.0 ? ", re-touch on" : "");
        } else if (!quiet) {
            printf("hold   : until SIGINT/SIGTERM (press Ctrl-C to release)\n");
        }

        double hold0 = now_sec();
        double deadline = (hold_secs >= 0.0) ? hold0 + hold_secs : -1.0;
        double next_cycle = (keep_interval > 0.0) ? hold0 + keep_interval : -1.0;
        unsigned cycle = 0;

        while (!g_stop) {
            double now = now_sec();
            if (deadline > 0.0 && now >= deadline)
                break;
            if (next_cycle > 0.0 && now >= next_cycle) {
                cycle++;
                /* 写入与上一周期不同的数据: 强制压缩页解压回 RAM、干净页重新变脏;
                 * -R 模式每轮换随机数据, 保持不可压缩 */
                unsigned char pat = (unsigned char)(0xA0 | (cycle & 0x0F));
                if (random_fill) {
                    fill_random(mem, size, cycle, random_pct);
                } else if (full_fill) {
                    memset(mem, pat, size);
                } else {
                    for (size_t off = 0; off < size && !g_stop; off += g_page)
                        mem[off] = (char)pat;
                }
                if (!quiet) {
                    printf("cycle  : %u re-touched %.2f MiB", cycle, to_mib(size));
                    unsigned long long r2 = get_rss_bytes();
                    if (r2)
                        printf(", rss %.2f MiB", to_mib(r2));
                    printf("\n");
                }
                next_cycle += keep_interval;
                continue;
            }
            struct timespec ts = { 0, 20 * 1000 * 1000 };  /* 20ms 轮询 */
            nanosleep(&ts, NULL);
        }
    }

    /* ---- 释放 ---- */
    munmap(mem, size);
    printf("release: munmap ok, total %.3f s, peak rss %.2f MiB\n",
           now_sec() - t_start, to_mib(get_peak_rss_bytes()));
    return 0;
}
Makefile编译 · host / ios / ohos 三目标 下载
# mem_alloc_bench — 跨平台构建
#
#   make            本机 (macOS/Linux) 编译 mem_stress + mem_bench
#   make ios        交叉编译 iOS arm64 二进制 (输出到 ios/)
#   make ohos       交叉编译 HarmonyOS arm64 二进制 (输出到 ohos/, 需 OHOS NDK)
#   make clean
#
# OHOS NDK 路径按实际安装位置覆盖, 例如:
#   make ohos OHOS_NATIVE=/path/to/openharmony/native

CC      ?= cc
CFLAGS  ?= -O2 -Wall -Wextra -std=c11
BINS     = mem_stress mem_bench

# ---- iOS (Xcode 自带工具链) ----
IOS_CC     := xcrun -sdk iphoneos clang
IOS_CFLAGS := -arch arm64 -O2 -Wall -Wextra -std=c11 -miphoneos-version-min=12.0

# ---- HarmonyOS (DevEco Studio 的 OHOS NDK, musl libc) ----
OHOS_NATIVE ?= /Applications/DevEco-Studio.app/Contents/sdk/default/openharmony/native
OHOS_CC     := $(OHOS_NATIVE)/llvm/bin/clang
# 真机 arm64 用 aarch64-linux-ohos; 模拟器改 x86_64-linux-ohos
OHOS_TRIPLE ?= aarch64-linux-ohos
OHOS_CFLAGS := --target=$(OHOS_TRIPLE) --sysroot=$(OHOS_NATIVE)/sysroot \
               -O2 -Wall -Wextra -std=c11

all: $(BINS)

mem_stress: mem_stress.c
	$(CC) $(CFLAGS) -o $@ $<

mem_bench: mem_bench.c
	$(CC) $(CFLAGS) -o $@ $<

ios: ios/mem_stress ios/mem_bench

ios/%: %.c
	@mkdir -p ios
	$(IOS_CC) $(IOS_CFLAGS) -o $@ $<

ohos: ohos/mem_stress ohos/mem_bench

ohos/%: %.c
	@mkdir -p ohos
	$(OHOS_CC) $(OHOS_CFLAGS) -o $@ $<

clean:
	rm -rf $(BINS) ios ohos

.PHONY: all ios ohos clean
compare_cases.py对比工具 · Python3 标准库 · 电脑侧执行 下载
#!/usr/bin/env python3
# compare_cases.py — 标准用例数据对比 (消费 run_case.sh 生成的 case-*.txt)
#
# 用法:
#   python3 compare_cases.py case-light-touch.txt case-heavy-touch.txt [...]   # 第一个文件为基准
#
# 输出: ① 耗时表   — 每文件一行 (fill/mmap/unmap/faults 计时与缺页指标)
#       ② 状态表   — pre_* (申请前) 与 post_* (申请驻留时) 全量指标
#                    (转置: 指标为行, 文件为列, 逐项 Δ vs 基准)
#       ③ 驻留开销  — post−pre 逐项差值 (申请 200M 对系统状态的净影响)
#       ④ Δ 汇总行 — 主指标相对基准变化
#       ⑤ 机器可读 key=value 行 (ROW/DELTA, 含全部 pre_*/post_*_avg/_pct 与 faults)
# 约定: pre_*/post_* 单位 MiB; -1/N/A = 平台无此指标 (如 iOS 无 pre_avail, Linux 无 pre_free_spec)
#       旧格式 case 文件 (无 post_*/faults) 仍可解析: 对应列显示 "-", post 块自动省略
# 仅依赖 Python3 标准库; 对比在采集侧(电脑)进行, 不要求 iOS 上有 python。
import sys

METRICS = ["total", "free", "avail", "free_spec", "file", "anon",
           "swap_comp", "comp_occ"]   # pre_<m> / post_<m>

def parse(path):
    case, recs = {}, []
    for line in open(path, encoding="utf-8", errors="replace"):
        line = line.strip()
        if not line:
            continue
        toks = line.split()
        if toks[0] not in ("CASE", "PHASE", "REC", "SUMMARY", "ERROR"):
            continue
        d = dict(t.split("=", 1) for t in toks[1:] if "=" in t)
        if toks[0] == "CASE":
            case = d
        elif toks[0] == "REC":
            recs.append(d)
    return case, recs

def num(d, key):
    try:
        return float(d[key])
    except (KeyError, ValueError):
        return None

def mean(xs):
    xs = [x for x in xs if x is not None]
    return sum(xs) / len(xs) if xs else None

def avg_key(recs, key):
    """REC 令牌求均值; 全 -1 (平台无此指标) -> None"""
    vals = [num(r, key) for r in recs]
    vals = [v for v in vals if v is not None and v != -1.0]
    return mean(vals) if vals else None

def pct(new, old):
    if new is None or old is None or old == 0:
        return None
    return (new - old) / old * 100.0

def fmt_pct(v):
    return ("%+.1f%%" % v) if v is not None else "-"

def fmt_int(v):
    return ("%d" % round(v)) if v is not None else "-"

def main():
    if len(sys.argv) < 2:
        print(__doc__)
        sys.exit(2)
    stats = []
    for p in sys.argv[1:]:
        case, recs = parse(p)
        if not recs:
            print("ERROR no REC in %s" % p, file=sys.stderr)
            sys.exit(3)
        pre = {("pre_" + m): avg_key(recs, "pre_" + m)
               for m in METRICS if ("pre_" + m) in recs[0]}
        post = {("post_" + m): avg_key(recs, "post_" + m)
                for m in METRICS if ("post_" + m) in recs[0]}
        stats.append({
            "file": p,
            "size_mib": case.get("size_mib", "?"),
            "mode": case.get("mode", "?"),
            "ballast": case.get("ballast_mib", "?"),
            "runs": len(recs),
            "fill_avg": mean([num(r, "fill_ms") for r in recs]),
            "fill_min": min(num(r, "fill_ms") for r in recs),
            "fill_max": max(num(r, "fill_ms") for r in recs),
            "unit_avg": mean([num(r, "unit") for r in recs]),
            "unit_label": recs[0].get("unit_label", "?"),
            "mmap_avg": mean([num(r, "mmap_us") for r in recs]),
            "unmap_avg": mean([num(r, "unmap_ms") for r in recs]),
            "faults": avg_key(recs, "faults"),
            "majflt": avg_key(recs, "majflt"),
            "pre": pre, "post": post,
            "has_post": bool(post),
        })
    base = stats[0]
    any_post = any(s["has_post"] for s in stats)
    print("COMPARE files=%d base=%s size_mib=%s mode=%s" %
          (len(stats), base["file"], base["size_mib"], base["mode"]))
    print()

    # ① 耗时表
    hdr = "%-28s %8s %4s  %-24s %16s %8s %8s %8s" % (
        "file", "ballast", "runs", "fill_ms avg/min/max",
        "unit", "mmap_us", "unmap_ms", "faults")
    print("[耗时表]")
    print(hdr)
    print("-" * len(hdr))
    for s in stats:
        print("%-28s %8s %4d  %6.2f / %6.2f / %6.2f  %10.1f %-7s %8.1f %8.1f %8s" % (
            s["file"], s["ballast"], s["runs"],
            s["fill_avg"], s["fill_min"], s["fill_max"],
            s["unit_avg"], s["unit_label"], s["mmap_avg"], s["unmap_avg"],
            fmt_int(s["faults"])))
    print()

    # ②③ 状态表 + 驻留开销
    def state_block(title, key_prefix, delta_vs_base):
        col_w = [max(len(s["file"]), 8) for s in stats]
        if delta_vs_base and len(stats) > 1:
            dlab = ["Δ"] if len(stats) == 2 else \
                   ["Δ:%s" % s["file"][:12] for s in stats[1:]]
            d_w = [max(len(l), 8) for l in dlab]
        print(title)
        print("%-13s" % "指标" +
              "".join("%*s" % (w + 2, s["file"]) for w, s in zip(col_w, stats)) +
              ("".join("%*s" % (w + 2, l) for w, l in zip(d_w, dlab))
               if delta_vs_base and len(stats) > 1 else ""))
        print("-" * (13 + sum(w + 2 for w in col_w) +
                     (sum(w + 2 for w in d_w) if delta_vs_base and len(stats) > 1 else 0)))
        for m in METRICS:
            k = key_prefix + m
            if not any(k in s[key_prefix[:-1]] for s in stats if key_prefix[:-1] in s):
                continue
            row = "%-13s" % m
            for s, w in zip(stats, col_w):
                v = s[key_prefix[:-1]].get(k)
                row += "%*s" % (w + 2, "N/A" if v is None else "%.1f" % v)
            if delta_vs_base and len(stats) > 1:
                for s, w in zip(stats[1:], d_w):
                    row += "%*s" % (w + 2, fmt_pct(
                        pct(s[key_prefix[:-1]].get(k), base[key_prefix[:-1]].get(k))))
            print(row)
        print()

    state_block("[pre_* 申请前快照] (每轮申请时刻前均值, MiB; N/A=平台无此指标)",
                "pre_", True)
    if any_post:
        state_block("[post_* 申请驻留时快照] (fill 后驻留期均值, MiB)", "post_", True)
        # 驻留开销 post - pre
        col_w = [max(len(s["file"]), 8) for s in stats]
        print("[驻留开销 post−pre] (申请 SIZE 对系统状态的净影响, MiB)")
        print("%-13s" % "指标" +
              "".join("%*s" % (w + 2, s["file"]) for w, s in zip(col_w, stats)))
        print("-" * (13 + sum(w + 2 for w in col_w)))
        for m in METRICS:
            kp, ks = "pre_" + m, "post_" + m
            if not any(s["has_post"] for s in stats):
                continue
            row = "%-13s" % m
            for s, w in zip(stats, col_w):
                a, b = s["pre"].get(kp), s["post"].get(ks)
                row += "%*s" % (w + 2, "-" if (a is None or b is None)
                                else "%+.1f" % (b - a))
            print(row)
        print()

    # ④ Δ 汇总
    if len(stats) > 1:
        for s in stats[1:]:
            print("DELTA %-28s vs base: fill_ms=%s unit=%s unmap_ms=%s faults=%s pre_free=%s" % (
                s["file"],
                fmt_pct(pct(s["fill_avg"], base["fill_avg"])),
                fmt_pct(pct(s["unit_avg"], base["unit_avg"])),
                fmt_pct(pct(s["unmap_avg"], base["unmap_avg"])),
                fmt_pct(pct(s["faults"], base["faults"])),
                fmt_pct(pct(s["pre"].get("pre_free"), base["pre"].get("pre_free")))))
        print()

    # ⑤ 机器可读行
    print("# 机器可读行 (key=value, 与用例记录同风格):")
    for s in stats:
        row = ("ROW file=%s size_mib=%s mode=%s ballast_mib=%s runs=%d "
               "fill_ms_avg=%.3f fill_ms_min=%.3f fill_ms_max=%.3f "
               "unit_avg=%.1f unit_label=%s mmap_us_avg=%.1f unmap_ms_avg=%.3f "
               "faults_avg=%s majflt_avg=%s" % (
                   s["file"], s["size_mib"], s["mode"], s["ballast"], s["runs"],
                   s["fill_avg"], s["fill_min"], s["fill_max"],
                   s["unit_avg"], s["unit_label"], s["mmap_avg"], s["unmap_avg"],
                   "-1" if s["faults"] is None else "%.1f" % s["faults"],
                   "-1" if s["majflt"] is None else "%.1f" % s["majflt"]))
        for m in METRICS:
            v = s["pre"].get("pre_" + m)
            row += " pre_%s_avg=%s" % (m, "-1" if v is None else "%.1f" % v)
        for m in METRICS:
            if s["has_post"]:
                v = s["post"].get("post_" + m)
                row += " post_%s_avg=%s" % (m, "-1" if v is None else "%.1f" % v)
        print(row)
    for s in stats[1:]:
        row = ("DELTA file=%s vs=%s fill_ms_pct=%s unit_pct=%s unmap_ms_pct=%s faults_pct=%s" % (
            s["file"], base["file"],
            fmt_pct(pct(s["fill_avg"], base["fill_avg"])),
            fmt_pct(pct(s["unit_avg"], base["unit_avg"])),
            fmt_pct(pct(s["unmap_avg"], base["unmap_avg"])),
            fmt_pct(pct(s["faults"], base["faults"]))))
        for m in METRICS:
            p = pct(s["pre"].get("pre_" + m), base["pre"].get("pre_" + m))
            if p is not None:
                row += " pre_%s_pct=%s" % (m, fmt_pct(p))
        if s["has_post"] and base["has_post"]:
            for m in METRICS:
                p = pct(s["post"].get("post_" + m), base["post"].get("post_" + m))
                if p is not None:
                    row += " post_%s_pct=%s" % (m, fmt_pct(p))
        print(row)

if __name__ == "__main__":
    main()