Re: [PATCH 5/6] perf_counter: add more context information

From: Corey Ashford
Date: Mon Apr 06 2009 - 17:15:39 EST




Peter Zijlstra wrote:
On Mon, 2009-04-06 at 13:16 -0700, Corey Ashford wrote:

One downside of this approach is that you if you specify "no header" (currently not possible, but maybe later?), you will not be able to get the level bits.
Would this be desirable?

I think it would. For one use case I'm working on right now, simple profiling, all I need are ip's. If I could omit the header, that would reduce the frequency of sigio's by a factor of three, and make it faster to read up the ip's when the SIGIO's occur.

Self-profiling?

So you're interested in getting the smallest possible record size, that
would still be 2 u64, right? Otherwise you don't get the IP context that
started this.



Self-profiling mainly, yes. PAPI specs an ability for remote monitoring of processes and threads, but I think it's only partially implemented.

So when you are talking about IP context, you mean pid/tid?

Regards,

- Corey

Corey Ashford
Software Engineer
IBM Linux Technology Center, Linux Toolchain
Beaverton, OR
503-578-3507
cjashfor@xxxxxxxxxx

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