pcp
[Top] [All Lists]

Re: [pcp] Slow pmdapapi fetching

To: fche@xxxxxxxxxx (Frank Ch. Eigler)
Subject: Re: [pcp] Slow pmdapapi fetching
From: Lukas Berk <lberk@xxxxxxxxxx>
Date: Tue, 27 Jan 2015 10:45:24 -0500
Cc: Nathan Scott <nathans@xxxxxxxxxx>, PCP <pcp@xxxxxxxxxxx>
Delivered-to: pcp@xxxxxxxxxxx
In-reply-to: <y0my4op9c7c.fsf@xxxxxxxx> (Frank Ch. Eigler's message of "Mon, 26 Jan 2015 21:41:59 -0500")
References: <258293690.15607144.1421974332709.JavaMail.zimbra@xxxxxxxxxx> <765513326.15612778.1421976592499.JavaMail.zimbra@xxxxxxxxxx> <y0my4op9c7c.fsf@xxxxxxxx>
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/24.4 (gnu/linux)
Hey Frank,

fche@xxxxxxxxxx (Frank Ch. Eigler) writes:
[...]
> The two commits on pcpfans.git fche/papi improve on this situation by
> moving code from the papi-pmda "inner loop" (the papi_fetchCallBack
> function) into the higher level papi_fetch one.  With default pminfo
> and papi-pmda batching values, both those pminfo calls should finish
> in much less than a second.  The knobs exposed by the code let you
> benchmark the improvements on your own hardware too.

Thanks for taking a look at this.  The changes look good to me.  I've
also verified that the updated QA passes all tests on my machine.

> Before:
>   # pmstore papi.control.batch 9999
>   # pmstore papi.control.reset ""
>   # /bin/time pminfo -f papi >/dev/null
> 0.00user 0.00system 0:02.68elapsed
>   # /bin/time pminfo -b1 -f papi >/dev/null
> 0.00user 0.01system 0:03.30elapsed
>
> After:
>   # pmstore papi.control.batch 10
>   # pmstore papi.control.reset ""
>   # /bin/time pminfo -f papi >/dev/null
> 0.00user 0.00system 0:00.19elapsed
>   # /bin/time pminfo -f papi >/dev/null
> 0.00user 0.00system 0:00.11elapsed

I'm also seeing a healthy performance improvement on my machine.

# time pminfo -v papi > /dev/null
Before:
real 0m3.070s, user 0m0.009s, sys 0m0.011s
real 0m0.726s, user 0m0.006s, sys 0m0.014s
real 0m0.713s, user 0m0.006s, sys 0m0.010s

After:
real 0m0.252s, user 0m0.009s, sys 0m0.011s
real 0m0.165s, user 0m0.005s, sys 0m0.010s
real 0m0.168s, user 0m0.008s, sys 0m0.006s

If the commits on fche/papi could get picked up for dev that'd be
greatly appreciated.

Cheers,

Lukas

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