gprof-learn - ZheNing Hu

Add a link parameter -pg during compilation; if using make, it would be CFLAGS+= -lg.

$ gprof -b git gmon.out  |head -64
Flat profile:

Each sample counts as 0.01 seconds.
  %   cumulative   self              self     total
 time   seconds   seconds    calls   s/call   s/call  name
 27.06      0.59     0.59  1968866     0.00     0.00  patch_delta
 16.51      0.95     0.36  2202293     0.00     0.00  unpack_object_header_buffer
 13.76      1.25     0.30  5327015     0.00     0.00  hashmap_get
 11.47      1.50     0.25   344036     0.00     0.00  unpack_entry
  8.72      1.69     0.19   521278     0.00     0.00  lookup_object
  4.13      1.78     0.09  1964667     0.00     0.00  hashmap_remove
  2.75      1.84     0.06   348709     0.00     0.00  get_object
  2.29      1.89     0.05        1     0.05     2.17  oid_array_for_each_unique
  1.38      1.92     0.03  6373452     0.00     0.00  use_pack
  0.92      1.94     0.02  2202293     0.00     0.00  unpack_compressed_entry
  0.92      1.96     0.02  1394836     0.00     0.00  grab_sub_body_contents
  0.92      1.98     0.02   348709     0.00     0.00  create_object
  0.92      2.00     0.02   348709     0.00     0.00  format_ref_array_item
  0.92      2.02     0.02    74557     0.00     0.00  fill_commit_graph_info

time: The percentage of total execution time spent in the function.
cumulative seconds: The sum of the execution time of the current function and all functions above it.
self seconds: The execution time of the current function alone.
calls: The total number of times the function was called. If the function was never called, or the number of calls could not be determined (possibly because the function was not compiled with profiling enabled), the calls field is empty.
self ms/call: If this function was profiled, the average number of microseconds per call; otherwise empty.
total ms/call: If this function was profiled, the average number of microseconds per call including its child functions; otherwise empty.
name: The name of the function.

References

Interpreting gprof’s Output

编译的时候加一个链接参数 -pg 如使用make 则是 CFLAGS+= -lg。

$ gprof -b git gmon.out  |head -64
Flat profile:

Each sample counts as 0.01 seconds.
  %   cumulative   self              self     total
 time   seconds   seconds    calls   s/call   s/call  name
 27.06      0.59     0.59  1968866     0.00     0.00  patch_delta
 16.51      0.95     0.36  2202293     0.00     0.00  unpack_object_header_buffer
 13.76      1.25     0.30  5327015     0.00     0.00  hashmap_get
 11.47      1.50     0.25   344036     0.00     0.00  unpack_entry
  8.72      1.69     0.19   521278     0.00     0.00  lookup_object
  4.13      1.78     0.09  1964667     0.00     0.00  hashmap_remove
  2.75      1.84     0.06   348709     0.00     0.00  get_object
  2.29      1.89     0.05        1     0.05     2.17  oid_array_for_each_unique
  1.38      1.92     0.03  6373452     0.00     0.00  use_pack
  0.92      1.94     0.02  2202293     0.00     0.00  unpack_compressed_entry
  0.92      1.96     0.02  1394836     0.00     0.00  grab_sub_body_contents
  0.92      1.98     0.02   348709     0.00     0.00  create_object
  0.92      2.00     0.02   348709     0.00     0.00  format_ref_array_item
  0.92      2.02     0.02    74557     0.00     0.00  fill_commit_graph_info

time: 函数在总调用时间占比。
cumulative seconds: 当前函数执行时间和之上所有函数执行时间的总和。
self seconds: 当前函数单独执行时间。
calls: 函数被调用的总次数。如果函数从未被调用，或者无法确定它被调用的次数(可能是因为函数没有启用分析编译)，则calls字段为空。
self ms/call: 如果这个函数被分析，则表示每次调用该函数的平均微秒数，否则为空。
total ms/call: 如果这个函数被分析，则表示所有调用该函数和其子函数的平均微秒数，否则为空。
name: 函数的名称。

参考

Interpreting gprof’s Output