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| author | Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com> | 2019-06-19 14:49:22 +0300 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-06-26 16:17:30 -0400 |
| commit | 0bdae7b3fbcd1d6d06096584915b9770fd07ccb2 (patch) | |
| tree | 97fa38a7971bbb0fcb834e6c8c00cfbfc9fc404b | |
| parent | 2daa6666765f6def370a1e5723f719f7174d12e2 (diff) | |
| download | trace-cmd-0bdae7b3fbcd1d6d06096584915b9770fd07ccb2.tar.gz | |
trace-cmd: Do not free pages from the lookup table in struct cpu_data in case trace file is loaded.
A major speed regression in trace-cmd v2.8 is reported by Johannes Berg
when parsing a huge trace.dat file:
"I have a ~1.7G file with just under 620k events (not exactly big by our standards),
and parsing speed (with -N to disable plugins) goes from ~4.5 seconds on commit
1ad32c24746 to >>4.5 minutes (I aborted there) on master.
I was talking to Steven about another issue, and he pointed me to
commit c2fc2bc296f7. Reverting that on master makes it take ~2 seconds,
so that'd actually be an improvement."
Proposed solution: do not free pages from "struct page **pages" lookup table
in struct cpu_data, in case a trace file is loaded. This reverts the behavior
for this use case, as it was before commit c2fc2bc296f7.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203411
Link: http://lore.kernel.org/linux-trace-devel/20190619114922.3169-1-tz.stoyanov@gmail.com
Fixes: c2fc2bc296f7 ("trace-cmd: Fix crash when trace-cmd is executed with args profile -F sleep 1")
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Tested-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| -rw-r--r-- | lib/trace-cmd/trace-input.c | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/lib/trace-cmd/trace-input.c b/lib/trace-cmd/trace-input.c index 61566bad..654101f5 100644 --- a/lib/trace-cmd/trace-input.c +++ b/lib/trace-cmd/trace-input.c @@ -986,15 +986,17 @@ static void __free_page(struct tracecmd_input *handle, struct page *page) free(page); - for (index = cpu_data->nr_pages - 1; index > 0; index--) - if (cpu_data->pages[index]) - break; - if (index < (cpu_data->nr_pages - 1)) { - pages = realloc(cpu_data->pages, (index + 1) * sizeof(*cpu_data->pages)); - if (!pages) - return; - cpu_data->pages = pages; - cpu_data->nr_pages = index + 1; + if (handle->use_pipe) { + for (index = cpu_data->nr_pages - 1; index > 0; index--) + if (cpu_data->pages[index]) + break; + if (index < (cpu_data->nr_pages - 1)) { + pages = realloc(cpu_data->pages, (index + 1) * sizeof(*cpu_data->pages)); + if (!pages) + return; + cpu_data->pages = pages; + cpu_data->nr_pages = index + 1; + } } } |