I have run callgrind with my application like this:
valgrind --tool=callgrind MyApplication
and then call:
callgrind_annotate --auto=yes ./callgrind.out.2489
I see output like:
768,097,560 PROGRAM TOTALS
--------------------------------------------------------------------------------
Ir file:function
--------------------------------------------------------------------------------
18,624,794 /build/buildd/eglibc-2.11.1/elf/dl-lookup.c:do_lookup_x
[/lib/ld-2.11.1.so]
18,149,492 /src/js/src/jsgc.cpp:JS_CallTracer'2
[/src/firefox-debug-objdir/js/src/libmozjs.so]
16,328,897 /src/layout/style/nsCSSDataBlock.cpp:nsCSSExpandedDataBlock::DoAssertInitialState()
[/src/firefox-debug-objdir/toolkit/library/libxul.so]
13,376,634 /build/buildd/eglibc-2.11.1/nptl/pthread_getspecific.c:pthread_getspecific
[/lib/libpthread-2.11.1.so]
13,005,623 /build/buildd/eglibc-2.11.1/malloc/malloc.c:_int_malloc
[/lib/libc-2.11.1.so]
10,404,453 ???:0x0000000000009190 [/usr/lib/libpangocairo-1.0.so.0.2800.0]
10,358,646 /src/xpcom/io/nsFastLoadFile.cpp:NS_AccumulateFastLoadChecksum(unsigned
int*, unsigned char const*, unsigned int, int)
[/src/firefox-debug-objdir/toolkit/library/libxul.so]
8,543,634 /src/js/src/jsscan.cpp:js_GetToken
[/src/firefox-debug-objdir/js/src/libmozjs.so]
7,451,273 /src/xpcom/typelib/xpt/src/xpt_arena.c:XPT_ArenaMalloc
[/src/firefox-debug-objdir/toolkit/library/libxul.so]
7,335,131 ???:g_type_check_instance_is_a [/usr/lib/libgobject-2.0.so.0.2400.0]
I have a few questions:
What does the number on the right mean? Does it mean it spend accumulative that long in calling the function on the right? How can I tell how many times that function has been called and Does that include the time spend in calling the functions called by that function?
What does line with ???
mean? e.g. ???:0x0000000000009190 [/usr/lib/libpangocairo-1.0.so.0.2800.0]
To use Callgrind, you must specify --tool=callgrind on the Valgrind command line or use the supplied script callgrind . Callgrind's cache simulation is based on the Cachegrind tool of the Valgrind package.
Overview. Callgrind is a profiling tool that records the call history among functions in a program's run as a call-graph. By default, the collected data consists of the number of instructions executed, their relationship to source lines, the caller/callee relationship between functions, and the numbers of such calls.
Callgrind records the count of instructions, not the actual time spent in a function. If you have a program where the bottleneck is file I/O, the costs associated with reading and writing files won't show up in the profile, as those are not CPU-intensive tasks.
Use KCachegrind. Deciphering the text output is just meaningless.
As Let_Me_Be already answered, KCachegrind is the preferred way to go. Also make sure the dot
command is available on your system in order to generate graphs with it. There's also the callgrind_annotate
tool, which can do some basic processing at the command-line level.
Regarding your second question, these are calls inside libraries without debugging information. Usually it's not that interesting, but if you really need that information, you should compile the library yourself with debugging symbols (and optimization flags, since you're profiling).
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