Re: No useful callgraphs on Fedora 27
William Cohen <[email protected]>
| Newsgroups | gmane.linux.oprofile |
|---|---|
| Message-ID | <[email protected]> |
On 02/11/2018 04:31 AM, Clemens Eisserer wrote: > Hi, > > I would like to use oprofile to analyze some interaction between a poor > performing graphical program and the Xorg x-server. > I know the function which consumes most of the cpu cycles (fbBltOne), > and a callstack could help to diagnose which X11 protocol request > causes this behaviour. > > However on fedora 27, despite having all the debuginfo-packages > installed, I don't get a useful callgraph: > > > CPU: AMD64 family15h, speed 4000 MHz (estimated) > Counted CPU_CLK_UNHALTED events (CPU Clocks not Halted) with a unit > mask of 0x00 (No unit mask) count 100000 > samples % image name symbol name > ------------------------------------------------------------------------------- > 167267 37.1351 libfb.so fbBltOne > 167267 100.000 libfb.so fbBltOne [self] > ------------------------------------------------------------------------------- > 45871 10.1839 libc-2.26.so __memcpy_ssse3 > 45871 100.000 libc-2.26.so __memcpy_ssse3 [self] > ------------------------------------------------------------------------------- > 17944 3.9838 kallsyms copy_user_generic_string > 17944 100.000 kallsyms copy_user_generic_string [self] > ------------------------------------------------------------------------------- > > Any ideas what could be wrong with my system? You might also get data with "perf record ..." and "perf report" to see if it has the same problem. It is possible that some of the recent changes patches for spectre might be causing a problem extracting backtraces. Similar problems have been observed in other tools such as systemtap: https://sourceware.org/ml/systemtap/2018-q1/msg00013.html -Wil > > Thank you in advance & best regards, Clemens > > PS: Sorry for the cross-post (sysprof mailing list), I posted there > before I realized there isn't much traffic going on. > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > oprofile-list mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/oprofile-list ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ oprofile-list mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/oprofile-list