Profiling sleep times with perf

Question

I was looking for a way to find out where my program spends time. I read the perf tutorial and tried to profile sleep times as it is described there. I wrote the simplest possib

Answer 1

This works for me for "perf version 3.11.1" on an "openSUSE 13.1 (x86_64)" box.

Here is the output if you care:

# ========
# captured on: Sun Feb 16 09:49:38 2014
# hostname : *****************
# os release : 3.11.10-7-desktop
# perf version : 3.11.1
# arch : x86_64
# nrcpus online : 8
# nrcpus avail : 8
# cpudesc : Intel(R) Core(TM) i7-3840QM CPU @ 2.80GHz
# cpuid : GenuineIntel,6,58,9
# total memory : 32945368 kB
# cmdline : /usr/bin/perf inject -v -s -i perf.data.raw -o perf.data 
# event : name = sched:sched_stat_sleep, type = 2, config = 0x48, config1 = 0x0, config2 = 0x
# event : name = sched:sched_switch, type = 2, config = 0x51, config1 = 0x0, config2 = 0x0, e
# event : name = sched:sched_process_exit, type = 2, config = 0x4e, config1 = 0x0, config2 = 
# HEADER_CPU_TOPOLOGY info available, use -I to display
# HEADER_NUMA_TOPOLOGY info available, use -I to display
# pmu mappings: cpu = 4, software = 1, tracepoint = 2, uncore_cbox_0 = 6, uncore_cbox_1 = 7, 
# ========
#
# Samples: 0  of event 'sched:sched_stat_sleep'
# Event count (approx.): 0
#
# Overhead        Period  Command  Shared Object  Symbol
# ........  ............  .......  .............  ......
#


# Samples: 8  of event 'sched:sched_switch'
# Event count (approx.): 80099958776
#
# Overhead        Period  Command      Shared Object             Symbol
# ........  ............  .......  .................  .................
#
   100.00%   80099958776      bla  [kernel.kallsyms]  [k] thread_return
                |
                --- thread_return
                    thread_return
                    do_nanosleep
                    hrtimer_nanosleep
                    SyS_nanosleep
                    system_call_fastpath
                    0x7fbc0dec6570
                    __GI___libc_nanosleep
                    (nil)



# Samples: 0  of event 'sched:sched_process_exit'
# Event count (approx.): 0
#
# Overhead        Period  Command  Shared Object  Symbol
# ........  ............  .......  .............  ......
#


#
# (For a higher level overview, try: perf report --sort comm,dso)
#
}