pcp
[Top] [All Lists]

Re: New perfevent PMDA

To: "White, Joseph" <jpwhite4@xxxxxxxxxxx>
Subject: Re: New perfevent PMDA
From: fche@xxxxxxxxxx (Frank Ch. Eigler)
Date: Thu, 26 Jun 2014 16:43:57 -0400
Cc: "pcp@xxxxxxxxxxx" <pcp@xxxxxxxxxxx>
Delivered-to: pcp@xxxxxxxxxxx
In-reply-to: <CFD1D0CD.C138%jpwhite4@xxxxxxxxxxx> (Joseph White's message of "Thu, 26 Jun 2014 17:29:50 +0000")
References: <CFD1D0CD.C138%jpwhite4@xxxxxxxxxxx>
User-agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/21.4 (gnu/linux)
Hi, Joe -

> [...] This linux-specific pmda exposes the hardware performance
> counters available on recent x86 systems. This pmda has been running
> on our cluster the last 10 months without problems (I've been
> meaning to submit this for inclusion for a while!). [...]

Thank you for posting.  As you probably know, we have recently started
expending effort in a very similar direction, so will need to compare
& contrast the two to figure out how to proceed.

Can you offer a few bits of explanation?

- We have considered using libpfm*/etc. also, but have been leaning toward
  papi, for cross-OS portability.  Did you also consider this?

- The systemwide permanent occupation of the hardware counters by the
  PMDA could easily be problematic.  Did you consider on-demand
  enablement instead?

- The configuration file appears to hard-code the perfcounters to be
  multiplexed/available.  Did you consider automatically enumerating
  all the available ones on the platform instead?

- Were you considering extending the PMDA to per-process or per-cgroup
  bindings?


- FChE

<Prev in Thread] Current Thread [Next in Thread>