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0ce2da1483
Adding the support to read rusage data once the workload is finished and
display the system/user time values:
$ perf stat --null perf bench sched pipe
...
Performance counter stats for 'perf bench sched pipe':
5.342599256 seconds time elapsed
2.544434000 seconds user
4.549691000 seconds sys
It works only in non -r mode and only for workload target.
So as of now, for workload targets, we display 3 types of timings. The
time we meassure in perf stat from enable to disable+period:
5.342599256 seconds time elapsed
The time spent in user and system lands, displayed only for workload
session/target:
2.544434000 seconds user
4.549691000 seconds sys
Those times are the very same displayed by 'time' tool. They are
returned by wait4 call via the getrusage struct interface.
Committer notes:
Had to rename some variables to avoid this on older systems such as
centos:6:
builtin-stat.c: In function 'print_footer':
builtin-stat.c:1831: warning: declaration of 'stime' shadows a global declaration
/usr/include/time.h:297: warning: shadowed declaration is here
Committer testing:
# perf stat --null time perf bench sched pipe
# Running 'sched/pipe' benchmark:
# Executed 1000000 pipe operations between two processes
Total time: 5.526 [sec]
5.526534 usecs/op
180945 ops/sec
1.00user 6.25system 0:05.52elapsed 131%CPU (0avgtext+0avgdata 8056maxresident)k
0inputs+0outputs (0major+606minor)pagefaults 0swaps
Performance counter stats for 'time perf bench sched pipe':
5.530978744 seconds time elapsed
1.004037000 seconds user
6.259937000 seconds sys
#
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180605121313.31337-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
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In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.