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2015-07-20perf bench futex: Add lock_pi stresserDavidlohr Bueso
Allows a way of measuring low level kernel implementation of FUTEX_LOCK_PI and FUTEX_UNLOCK_PI. The program comes in two flavors: (i) single futex (default), all threads contend on the same uaddr. For the sake of the benchmark, we call into kernel space even when the lock is uncontended. The kernel will set it to TID, any waters that come in and contend for the pi futex will be handled respectively by the kernel. (ii) -M option for multiple futexes, each thread deals with its own futex. This is a trivial scenario and only measures kernel handling of 0->TID transition. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Mel Gorman <mgorman@suse.de> Link: http://lkml.kernel.org/r/1436259353.12255.78.camel@stgolabs.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08perf bench futex: Support parallel waker threadsDavidlohr Bueso
The futex-wake benchmark only measures wakeups done within a single process. While this has value in its own, it does not really generate any hb->lock contention. A new benchmark 'wake-parallel' is added, by extending the futex-wake code such that we can measure parallel waker threads. The program output shows the avg per-thread latency in order to complete its share of wakeups: Run summary [PID 13474]: blocking on 512 threads (at [private] futex 0xa88668), 8 threads waking up 64 at a time. [Run 1]: Avg per-thread latency (waking 64/512 threads) in 0.6230 ms (+-15.31%) [Run 2]: Avg per-thread latency (waking 64/512 threads) in 0.5175 ms (+-29.95%) [Run 3]: Avg per-thread latency (waking 64/512 threads) in 0.7578 ms (+-18.03%) [Run 4]: Avg per-thread latency (waking 64/512 threads) in 0.8944 ms (+-12.54%) [Run 5]: Avg per-thread latency (waking 64/512 threads) in 1.1204 ms (+-23.85%) Avg per-thread latency (waking 64/512 threads) in 0.7826 ms (+-9.91%) Naturally, different combinations of numbers of blocking and waker threads will exhibit different information. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Davidlohr Bueso <dbueso@suse.de> Link: http://lkml.kernel.org/r/1431110280-20231-1-git-send-email-dave@stgolabs.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-06-19perf bench: Add --repeat optionDavidlohr Bueso
There are a number of benchmarks that do single runs and as a result does not really help users gain a general idea of how the workload performs. So the user must either manually do multiple runs or just use single bogus results. This option will enable users to specify the amount of runs (arbitrarily defaulted to 10, to use the existing benchmarks default) through the '--repeat' option. Add it to perf-bench instead of implementing it always in each specific benchmark. Signed-off-by: Davidlohr Bueso <davidlohr@hp.com> Cc: Aswin Chandramouleeswaran <aswin@hp.com> Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Jiri Olsa <jolsa@kernel.org> Link: http://lkml.kernel.org/r/1402942467-10671-2-git-send-email-davidlohr@hp.com [ Kept the existing default of 10, changing it to something else should be done on separate patch ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-04-14perf bench: Update manpage to mention numa and futexRamkumar Ramachandra
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1395964219-22173-3-git-send-email-artagnon@gmail.com Signed-off-by: Jiri Olsa <jolsa@redhat.com>
2012-07-02perf bench: Fix confused variable namings and descriptions in mem subsystemHitoshi Mitake
As Namhyung Kim pointed, there are confused namings and descriptions of words "cycle" and "clock" in mem-memset.c and mem-memcpy.c. With the option "-c" (or "--clock", now renamed as "--cycle"), mem subsystem measures cost of memset() and memcpy() with cpu-cycles event. But current mem subsystem source code contains lots of confused variable namings and descriptions with "clock" (e.g. the variable use_clock). This is a very bad style because there is another software event named "cpu-clock". This patch replaces wrong usage of "clock" to "cycle". v2: modified Documentation/perf-bench.txt for the descriptions of --cycle option Signed-off-by: Hitoshi Mitake <h.mitake@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/1341236777-18457-1-git-send-email-h.mitake@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-06-27perf bench: Documentation updateNamhyung Kim
The current perf-bench documentation has a couple of typos and even lacks entire description of mem subsystem. Fix it. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1340172486-17805-1-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-05-05perf tools: Fixup minor doc formatting issuesArnaldo Carvalho de Melo
Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-08perf: cleanup some DocumentationRandy Dunlap
Correct typos in perf bench & perf sched help text. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>, Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20100331113100.cc898487.randy.dunlap@oracle.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
2009-11-10perf bench: Add new document about perf-benchHitoshi Mitake
This patch adds new document about perf-bench. Man page and html will be provided for user. Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1257853855-28934-3-git-send-email-mitake@dcl.info.waseda.ac.jp> Signed-off-by: Ingo Molnar <mingo@elte.hu>