Linux perf 工具 - 如何同时分析多个进程？如何提取 CPU 周期的百分比？

Question

我正在尝试在我的 CPU 上分析一组进程。为了非常精确，我想使用perf stat命令来查看我的进程使用了​​多少 CPU 周期。这与 top 不同，在那里我只看到快照中使用的 CPU 百分比。

不幸的是，我没有找到同时分析多个进程的方法。这可能吗？

作为第二个问题：是否可以不仅看到使用的 CPU 周期，还可以看到在同一时间间隔内使用的 CPU 周期总量（或百分比）？

Answer 1

您可以尝试perf stat -p PID1,PID2,PID3为您想要的每个 pid运行（使用 pidof、pgrep 等获取它们...）http://man7.org/linux/man-pages/man1/perf-stat.1.html

 -p, --pid=<pid>
    stat events on existing process id (comma separated list)

还有一个有用的-I msecs选项来启用定期打印和--per-thread分离线程。

还可以尝试在系统范围内perf stat -a使用-A或一些 --per-* 选项：http ://man7.org/linux/man-pages/man1/perf-stat.1.html

   -a, --all-cpus
       system-wide collection from all CPUs (default if no target is
       specified)
   -A, --no-aggr
       Do not aggregate counts across all monitored CPUs.

   --per-socket
       Aggregate counts per processor socket for system-wide mode
       measurements. This is a useful mode to detect imbalance between
       sockets. To enable this mode, use --per-socket in addition to -a.
       (system-wide). The output includes the socket number and the
       number of online processors on that socket. This is useful to
       gauge the amount of aggregation.

   --per-core
       Aggregate counts per physical processor for system-wide mode
       measurements. This is a useful mode to detect imbalance between
       physical cores. To enable this mode, use --per-core in addition
       to -a. (system-wide). The output includes the core number and the
       number of online logical processors on that physical processor.

   --per-thread
       Aggregate counts per monitored threads, when monitoring threads
       (-t option) or processes (-p option).