我编写了一个用于监视子进程资源的程序。我使用 wait4 函数的第四个参数来获取子进程的 CPU 使用率，效果很好。但我可以用它来获取内存使用情况，它看起来与“ps”的输出不同。我也尝试解析/proc/pid/status，但有时它并不准确，因为某些子进程解析得太快。有人可以给我一些建议或解决方案吗？非常感谢。
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一旦进程终止，即使进程入口仍然存在于内核中，该进程的所有资源都会被内核释放。所以，我不希望能够从 /proc 读取进程的内存大小。
此外，该进程没有“使用的最大内存”统计信息。
我能想到的确定进程最大内存量的唯一方法如下：
- 在执行时定期对进程状态进行采样并获取当前内存使用情况，
- 用于
strace捕获进程进行的所有系统调用并对其进行处理以确定进程使用了多少内存，或者 - 使用共享库来拦截进程进行的内存分配系统调用，捕获详细信息并找到报告的方法
除非绝对需要非常高的准确性，否则我可能会选择（1）。
可能有分析或统计工具可以帮助完成这项任务，但我不知道。
使用跟踪
这是一个程序，说明了strace用于此目的的用途：
allocit.c
#include <stdio.h>
#include <stdlib.h>
int main ()
{
int cur;
cur = 0;
while ( cur < 1000 )
{
malloc(1024);
cur++;
}
return 0;
}
使用 strace ( strace ./allocit) 运行它会得到如下输出：
execve("./allocit", ["./allocit"], [/* 49 vars */]) = 0
brk(0) = 0x1b991000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x2ae49dccd000
uname({sys="Linux", node="fearless.office.tmcs", ...}) = 0
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/home/jdoe/lib/tls/x86_64/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/home/jdoe/lib/tls/x86_64", 0x7fff896b2900) = -1 ENOENT (No such file or directory)
open("/home/jdoe/lib/tls/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/home/jdoe/lib/tls", 0x7fff896b2900) = -1 ENOENT (No such file or directory)
open("/home/jdoe/lib/x86_64/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/home/jdoe/lib/x86_64", 0x7fff896b2900) = -1 ENOENT (No such file or directory)
open("/home/jdoe/lib/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/home/jdoe/lib", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
open("/software/ticketmaster/lib/tls/x86_64/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/software/ticketmaster/lib/tls/x86_64", 0x7fff896b2900) = -1 ENOENT (No such file or directory)
open("/software/ticketmaster/lib/tls/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/software/ticketmaster/lib/tls", 0x7fff896b2900) = -1 ENOENT (No such file or directory)
open("/software/ticketmaster/lib/x86_64/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/software/ticketmaster/lib/x86_64", 0x7fff896b2900) = -1 ENOENT (No such file or directory)
open("/software/ticketmaster/lib/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/software/ticketmaster/lib", 0x7fff896b2900) = -1 ENOENT (No such file or directory)
open("/usr/lib/oracle/11.2/client64/lib/tls/x86_64/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/usr/lib/oracle/11.2/client64/lib/tls/x86_64", 0x7fff896b2900) = -1 ENOENT (No such file or directory)
open("/usr/lib/oracle/11.2/client64/lib/tls/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/usr/lib/oracle/11.2/client64/lib/tls", 0x7fff896b2900) = -1 ENOENT (No such file or directory)
open("/usr/lib/oracle/11.2/client64/lib/x86_64/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/usr/lib/oracle/11.2/client64/lib/x86_64", 0x7fff896b2900) = -1 ENOENT (No such file or directory)
open("/usr/lib/oracle/11.2/client64/lib/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/usr/lib/oracle/11.2/client64/lib", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=123338, ...}) = 0
mmap(NULL, 123338, PROT_READ, MAP_PRIVATE, 3, 0) = 0x2ae49dcce000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\220\332!\2359\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1717800, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x2ae49dced000
mmap(0x399d200000, 3498328, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x399d200000
mprotect(0x399d34e000, 2093056, PROT_NONE) = 0
mmap(0x399d54d000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x14d000) = 0x399d54d000
mmap(0x399d552000, 16728, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x399d552000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x2ae49dcee000
arch_prctl(ARCH_SET_FS, 0x2ae49dcee210) = 0
mprotect(0x399d54d000, 16384, PROT_READ) = 0
mprotect(0x399d01b000, 4096, PROT_READ) = 0
munmap(0x2ae49dcce000, 123338) = 0
brk(0) = 0x1b991000
brk(0x1b9b2000) = 0x1b9b2000
brk(0x1b9d3000) = 0x1b9d3000
brk(0x1b9f4000) = 0x1b9f4000
brk(0x1ba15000) = 0x1ba15000
brk(0x1ba36000) = 0x1ba36000
brk(0x1ba57000) = 0x1ba57000
brk(0x1ba78000) = 0x1ba78000
brk(0x1ba99000) = 0x1ba99000
exit_group(0) = ?
注意所有brk()用于扩展堆的调用。
于 2013-09-02T03:43:44.040 回答