perf record: Add record.build-id config option
Namhyung Kim
maintainerPATCH 1/1 perf record: Add record.build-id config option
Post processing at perf record takes long time on big machines. What it does is to find build-id of related binaries. Sometimes we just want to skip the processing and get the result quickly. Add a new config option to control this behavior.
The record.build-id config variable can have one of following:
- cache: post-process data and save/update the binaries into the build-id cache (in ~/.debug). This is default.
- no-cache: post-process data but not update the build-id cache. Same effect with using -N option.
- skip: skip post-processing and not update the cache. Same effect with using -B option.
--- tools/perf/Documentation/perf-record.txt | 11 ++++++++++- tools/perf/builtin-record.c | 13 +++++++++++++ 2 files changed, 23 insertions(+), 1 deletion(-)
tools/perf/Documentation/perf-record.txt +10 -1
@@ -207,11 +207,20 @@ comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0- 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. +-B:: +--no-buildid:: +Do not save the buildid of (used) binaries in the data file. This skips +post-processing after recoring which might take some time on big machines. +The Downside is that it can resolve into a wrong symbol after a binary is +rebuilt later. You can also set "record.build-id" config variable to +'skip' to have same effect. + -N:: --no-buildid-cache:: Do not update the buildid cache. This saves some overhead in situations where the information in the perf.data file (which includes buildids) -is sufficient. +is sufficient. You can also set "record.build-id" config variable to +'no-cache' to have same effect. -G name,...:: --cgroup name,...::
tools/perf/builtin-record.c +13 -0
@@ -837,6 +837,19 @@ int record_callchain_opt(const struct option *opt,static int perf_record_config (const char *var,const char *value,void *cb) { +struct record *rec = cb; + +if (!strcmp (var,"record.build-id" )) { +if (!strcmp (value,"cache" )) + rec->no_buildid_cache = false; +else if (!strcmp (value,"no-cache" )) + rec->no_buildid_cache = true; +else if (!strcmp (value,"skip" )) + rec->no_buildid = true; +else +return -1 ; +return 0 ; + }if (!strcmp (var,"record.call-graph" )) var ="call-graph.record-mode" ;/* fall-through */
Signature · 1 line
2.6.4
Quoted 5 lines · Namhyung Kim
Post processing at perf record takes long time on big machines. What it does is to find build-id of related binaries. Sometimes we just want to skip the processing and get the result quickly. Add a new config option to control this behavior.
Quoted 8 lines
The record.build-id config variable can have one of following:
- cache: post-process data and save/update the binaries into the build-id cache (in ~/.debug). This is default.
- no-cache: post-process data but not update the build-id cache. Same effect with using -N option.
- skip: skip post-processing and not update the cache. Same effect with using -B option.
thanks,
jirka
Quoted 7 lines · Namhyung Kim
Post processing at perf record takes long time on big machines. What it does is to find build-id of related binaries. Sometimes we just want to skip the processing and get the result quickly. Add a new config option to control this behavior.
The record.build-id config variable can have one of following:
Quoted 8 lines
- cache: post-process data and save/update the binaries into the build-id cache (in ~/.debug). This is default.
- no-cache: post-process data but not update the build-id cache. Same effect with using -N option.
- skip: skip post-processing and not update the cache. Same effect with using -B option.Reported-by Peter Zijlstra <[email protected]>
Nice!
Em Tue, Dec 15, 2015 at 10:49:56AM +0900, Namhyung Kim escreveu:
Quoted 4 lines
Post processing at perf record takes long time on big machines. What it does is to find build-id of related binaries. Sometimes we just want to skip the processing and get the result quickly. Add a new config option to control this behavior.
Applied, after changing the above comment to:
-------------------------------------------------------------------
Post processing at 'perf record' takes a long time on big machines.
What it does is to find the build-id of binaries found in the event stream, so that it can make sure, at report time, that the symtabs (Be it ELF, kallsyms, etc) being used to resolve symbols are the ones matching the binaries found at record time.
Sometimes we just want to skip this processing of events at the end of the session to get quicker results, making sure the binaries haven't changed from 'record' to 'report' time.
-------------------------------------------------------------------
The comments on the documentation already stressed that, but I improved that a bit as well
Quoted 22 lines
The record.build-id config variable can have one of following:
- cache: post-process data and save/update the binaries into the build-id cache (in ~/.debug). This is default.
- no-cache: post-process data but not update the build-id cache. Same effect with using -N option.
- skip: skip post-processing and not update the cache. Same effect with using -B option.Reported-by Peter Zijlstra <[email protected]>Cc Taeung Song <[email protected]>Signed-off-by Namhyung Kim <[email protected]>--- tools/perf/Documentation/perf-record.txt | 11 ++++++++++- tools/perf/builtin-record.c | 13 +++++++++++++ 2 files changed, 23 insertions(+), 1 deletion(-)tools/perf/Documentation/perf-record.txt +0
-0
tools/perf/Documentation/perf-record.txt comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0- · line 216
Quoted 10 lines
tools/perf/Documentation/perf-record.txt +7
-0@@ -207,11 +207,20 @@ comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0- 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. +-B:: +--no-buildid:: +Do not save the buildid of (used) binaries in the data file. This skips +post-processing after recoring which might take some time on big machines. +The Downside is that it can resolve into a wrong symbol after a binary is +rebuilt later. You can also set "record.build-id" config variable to +'skip' to have same effect.
Do not save the build ids of binaries in the perf.data files. This skips post processing after recording, which sometimes makes the final step in the recording process to take a long time, as it needs to process all events looking for mmap records. The downside is that it can misresolve symbols if the workload binaries used when recording get locally rebuilt or upgraded, because the only key available in this case is the pathname. You can also set the "record.build-id" config variable to 'skip to have this behaviour permanently.
tools/perf/Documentation/perf-record.txt comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0- · line 223
Quoted 8 lines
tools/perf/Documentation/perf-record.txt +3
-1+ -N:: --no-buildid-cache:: Do not update the buildid cache. This saves some overhead in situations where the information in the perf.data file (which includes buildids) -is sufficient. +is sufficient. You can also set "record.build-id" config variable to +'no-cache' to have same effect.
the
the
Quoted 29 lines
tools/perf/Documentation/perf-record.txt +0
-0-G name,...:: --cgroup name,...::tools/perf/builtin-record.c +13
-0@@ -837,6 +837,19 @@ int record_callchain_opt(const struct option *opt,static int perf_record_config (const char *var,const char *value,void *cb) { +struct record *rec = cb; + +if (!strcmp (var,"record.build-id" )) { +if (!strcmp (value,"cache" )) + rec->no_buildid_cache = false; +else if (!strcmp (value,"no-cache" )) + rec->no_buildid_cache = true; +else if (!strcmp (value,"skip" )) + rec->no_buildid = true; +else +return -1 ; +return 0 ; + }if (!strcmp (var,"record.call-graph" )) var ="call-graph.record-mode" ;/* fall-through */ Signature · 1 line
2.6.4
tip-bot for Namhyung Kim
merge botperf record: Add record.build-id config option
Commit-ID: 7a29c087ff80f5d534bd6729c852099fc572c8d0 Gitweb: http://git.kernel.org/tip/7a29c087ff80f5d534bd6729c852099fc572c8d0 Author: Namhyung Kim <[email protected]> AuthorDate: Tue, 15 Dec 2015 10:49:56 +0900 Committer: Arnaldo Carvalho de Melo <[email protected]> CommitDate: Tue, 15 Dec 2015 11:46:16 -0300
perf record: Add record.build-id config option
Post processing at 'perf record' takes a long time on big machines.
What it does is to find the build-id of binaries found in the event stream, so that it can make sure, at 'report' time, that the symtabs (be it ELF, kallsyms, etc) being used to resolve symbols are the ones matching the binaries found at 'record' time.
Sometimes we just want to skip this processing of events at the end of the session to get quicker results, making sure the binaries haven't changed from 'record' to 'report' time.
Add a new config option to control this behavior.
The record.build-id config variable can have one of the following values:
- cache: post-process data and save/update the binaries into the build-id cache (in ~/.debug). This is the default.
- no-cache: post-process the data but not update the build-id cache. Same effect as using the -N option.
- skip: skip post-processing and do not update the cache. Same effect as using the -B option.
--- tools/perf/Documentation/perf-record.txt | 14 +++++++++++++- tools/perf/builtin-record.c | 13 +++++++++++++ 2 files changed, 26 insertions(+), 1 deletion(-)
tools/perf/Documentation/perf-record.txt +13 -1
@@ -207,11 +207,23 @@ comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0- 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. +-B:: +--no-buildid:: +Do not save the build ids of binaries in the perf.data files. This skips +post processing after recording, which sometimes makes the final step in +the recording process to take a long time, as it needs to process all +events looking for mmap records. The downside is that it can misresolve +symbols if the workload binaries used when recording get locally rebuilt +or upgraded, because the only key available in this case is the +pathname. You can also set the "record.build-id" config variable to +'skip to have this behaviour permanently. + -N:: --no-buildid-cache:: Do not update the buildid cache. This saves some overhead in situations where the information in the perf.data file (which includes buildids) -is sufficient. +is sufficient. You can also set the "record.build-id" config variable to +'no-cache' to have the same effect. -G name,...:: --cgroup name,...::
tools/perf/builtin-record.c +13 -0
@@ -837,6 +837,19 @@ int record_callchain_opt(const struct option *opt,static int perf_record_config (const char *var,const char *value,void *cb) { +struct record *rec = cb; + +if (!strcmp (var,"record.build-id" )) { +if (!strcmp (value,"cache" )) + rec->no_buildid_cache = false; +else if (!strcmp (value,"no-cache" )) + rec->no_buildid_cache = true; +else if (!strcmp (value,"skip" )) + rec->no_buildid = true; +else +return -1 ; +return 0 ; + }if (!strcmp (var,"record.call-graph" )) var ="call-graph.record-mode" ;/* fall-through */
Hi, Namhyung
I found accidentally a missing thing on Documentation/perf-record.txt. A trifling thing..
Quoted 53 lines · tip-bot for Namhyung Kim
Commit-ID: 7a29c087ff80f5d534bd6729c852099fc572c8d0 Gitweb: http://git.kernel.org/tip/7a29c087ff80f5d534bd6729c852099fc572c8d0 Author: Namhyung Kim <[email protected]> AuthorDate: Tue, 15 Dec 2015 10:49:56 +0900 Committer: Arnaldo Carvalho de Melo <[email protected]> CommitDate: Tue, 15 Dec 2015 11:46:16 -0300perf record: Add record.build-id config option
Post processing at 'perf record' takes a long time on big machines.
What it does is to find the build-id of binaries found in the event stream, so that it can make sure, at 'report' time, that the symtabs (be it ELF, kallsyms, etc) being used to resolve symbols are the ones matching the binaries found at 'record' time.
Sometimes we just want to skip this processing of events at the end of the session to get quicker results, making sure the binaries haven't changed from 'record' to 'report' time.
Add a new config option to control this behavior.
The record.build-id config variable can have one of the following values:
- cache: post-process data and save/update the binaries into the build-id cache (in ~/.debug). This is the default.
- no-cache: post-process the data but not update the build-id cache. Same effect as using the -N option.
- skip: skip post-processing and do not update the cache. Same effect as using the -B option.Reported-and-Acked-by Peter Zijlstra (Intel) <[email protected]>Signed-off-by Namhyung Kim <[email protected]>Acked-by Jiri Olsa <[email protected]>Cc David Ahern <[email protected]>Cc Taeung Song <[email protected]>[ Added some more text to the documentation ]Signed-off-by Arnaldo Carvalho de Melo <[email protected]>--- tools/perf/Documentation/perf-record.txt | 14 +++++++++++++- tools/perf/builtin-record.c | 13 +++++++++++++ 2 files changed, 26 insertions(+), 1 deletion(-)tools/perf/Documentation/perf-record.txt +0
-0@@ -207,11 +207,23 @@ comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0- 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.
tools/perf/Documentation/perf-record.txt comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0- · line 219
Quoted 10 lines
tools/perf/Documentation/perf-record.txt +10
-0+-B:: +--no-buildid:: +Do not save the build ids of binaries in the perf.data files. This skips +post processing after recording, which sometimes makes the final step in +the recording process to take a long time, as it needs to process all +events looking for mmap records. The downside is that it can misresolve +symbols if the workload binaries used when recording get locally rebuilt +or upgraded, because the only key available in this case is the +pathname. You can also set the "record.build-id" config variable to +'skip to have this behaviour permanently.
The 'skip' needs to be surrounded by single quotes. A single quote is missing.
Thanks,
Taeung
Quoted 36 lines
tools/perf/Documentation/perf-record.txt +3
-1+ -N:: --no-buildid-cache:: Do not update the buildid cache. This saves some overhead in situations where the information in the perf.data file (which includes buildids) -is sufficient. +is sufficient. You can also set the "record.build-id" config variable to +'no-cache' to have the same effect. -G name,...:: --cgroup name,...::tools/perf/builtin-record.c +13
-0@@ -837,6 +837,19 @@ int record_callchain_opt(const struct option *opt,static int perf_record_config (const char *var,const char *value,void *cb) { +struct record *rec = cb; + +if (!strcmp (var,"record.build-id" )) { +if (!strcmp (value,"cache" )) + rec->no_buildid_cache = false; +else if (!strcmp (value,"no-cache" )) + rec->no_buildid_cache = true; +else if (!strcmp (value,"skip" )) + rec->no_buildid = true; +else +return -1 ; +return 0 ; + }if (!strcmp (var,"record.call-graph" )) var ="call-graph.record-mode" ;/* fall-through */