aboutsummaryrefslogtreecommitdiffstats
path: root/tools/perf/Documentation
diff options
context:
space:
mode:
authorStephane Eranian <eranian@google.com>2010-06-17 11:39:01 +0200
committerArnaldo Carvalho de Melo <acme@redhat.com>2010-06-17 10:20:44 -0300
commita1ac1d3c085420ea8c809ebbee3bb212ed3616bd (patch)
treeaca14b46e24f277fe7601457039ef5e5ef1421f9 /tools/perf/Documentation
parent70c3856b2f1304e0abc65f1b96a8c60ddfc0fb9e (diff)
downloadkernel_samsung_tuna-a1ac1d3c085420ea8c809ebbee3bb212ed3616bd.zip
kernel_samsung_tuna-a1ac1d3c085420ea8c809ebbee3bb212ed3616bd.tar.gz
kernel_samsung_tuna-a1ac1d3c085420ea8c809ebbee3bb212ed3616bd.tar.bz2
perf record: Add option to avoid updating buildid cache
There are situations where there is enough information in the perf.data to process the samples. Updating the buildid cache may add unecessary overhead in terms of disk space and time (copying large elf images). A persistent option to do this already exists via the perfconfig file, simply do: [buildid] dir = /dev/null This patch provides a way to suppress builid cache updates on a per-run basis. It addds a new option, -N, to perf record. Buildids are still generated in the perf.data file. Cc: David S. Miller <davem@davemloft.net> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <4c19ef89.93ecd80a.40dc.fffff8e9@mx.google.com> Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/Documentation')
-rw-r--r--tools/perf/Documentation/perf-record.txt6
1 files changed, 6 insertions, 0 deletions
diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index 25576b4..3ee27dc 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -110,6 +110,12 @@ comma-sperated list with no space: 0,1. Ranges of CPUs are specified with -: 0-2
In per-thread mode with inheritance mode on (default), samples are captured only when
the thread executes on the designated CPUs. Default is to monitor all CPUs.
+-N::
+--no-buildid-cache::
+Do not update the builid cache. This saves some overhead in situations
+where the information in the perf.data file (which includes buildids)
+is sufficient.
+
SEE ALSO
--------
linkperf:perf-stat[1], linkperf:perf-list[1]