This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: [PATCH] Don't use SSE4_2 instructions on Intel Silvermont Micro Architecture.
- From: OndÅej BÃlka <neleai at seznam dot cz>
- To: Andi Kleen <andi at firstfloor dot org>
- Cc: Carlos O'Donell <carlos at redhat dot com>, Dmitrieva Liubov <liubov dot dmitrieva at gmail dot com>, "H.J. Lu" <hjl dot tools at gmail dot com>, GNU C Library <libc-alpha at sourceware dot org>
- Date: Fri, 21 Jun 2013 03:24:27 +0200
- Subject: Re: [PATCH] Don't use SSE4_2 instructions on Intel Silvermont Micro Architecture.
- References: <CAHjhQ93zmP525hqW-2RnHBREc_949XLnm7sE-CSv3Nj8PQgUig at mail dot gmail dot com> <CAMe9rOqT31AFq1S3V0Krh2CZnHu=FiyXqhg840fimRtfU4_hXQ at mail dot gmail dot com> <20130618064910 dot GA19972 at domone dot kolej dot mff dot cuni dot cz> <CAHjhQ90Fc0kdZfQrUwLwpKbz2va4X9rzf1EkGD-s-RH-iF7guQ at mail dot gmail dot com> <CAHjhQ92qfjdKZthqAwxCVuCnLqDr2stdEbQpne5rKhzJPeN_cQ at mail dot gmail dot com> <51C23583 dot 1070307 at redhat dot com> <CAHjhQ93vWnCiVVU9MPoGptjQtn2J2PCDT2B7ZfXiKt+Cv_Rh_w at mail dot gmail dot com> <51C307A5 dot 7030608 at redhat dot com> <20130620151711 dot GA4891 at domone dot kolej dot mff dot cuni dot cz> <51C317AA dot 6080502 at redhat dot com>
On Thu, Jun 20, 2013 at 10:54:34AM -0400, Carlos O'Donell wrote:
> On 06/20/2013 11:17 AM, OndÅej BÃlka wrote:
> > On Thu, Jun 20, 2013 at 09:46:13AM -0400, Carlos O'Donell wrote:
> >> On 06/20/2013 09:10 AM, Dmitrieva Liubov wrote:
> >>> What benchmarks do you mean? string/test-str** unit tests?
> >>
> >> I mean the new glibc microbenchmark suite :-)
> >>
>
> > What you have is currently nowhere near of state where you can get
> > usable results by it. It has five major flaws that i wrote earlier and
> > any of them is enough to have paper immidiately rejected.
>
> Please help us make the microbenchmark better.
>
Already tried and will not make same mistake again. Making it better is
simple, run it and check if outputs make sense. For two months a
performance of several functions was 100 times faster than it shoud be.
I do not have any confidence in benchmarks where you do not do such
basic stuff.
> Until then it's what I'm going to use to determine if Dmitrieva's
> patch makes performance objectively faster.
>
You said that you want performance objectively faster. A definition of objective is:
Condition in the realm of sensible experience independent of individual
thought and perceptible by all observer.
To see if this is a case I added Andi. Andi, could you browse sources
and tell if you think that benchtests are adequate to measure
performance?