Re: [PATCH 2/2] perf callchain: Use global caching provided by libunwind

From: Namhyung Kim
Date: Tue Sep 23 2014 - 08:54:15 EST


On Tue, Sep 23, 2014 at 9:28 PM, Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
> On Tue, Sep 23, 2014 at 03:30:28PM +0900, Namhyung Kim wrote:
>> The libunwind provides two caching policy which are global and
>> per-thread. As perf unwinds callchains in a single thread, it'd
>> sufficient to use global caching.
>>
>> This speeds up my perf report from 14s to 7s on a ~260MB data file.
>> Although the output contains a slight difference (~0.01% in terms of
>> number of lines printed) on callchains which were not resolved.
>
> hum, the speedup is nice, but what was the diff output.. any example?
> The new version does not print some lines or different ones?

I don't have the result now - will post the diff when I go to the
office tomorrow. But IIRC new version only adds new lines..

Thanks,
Namhyung
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