From mboxrd@z Thu Jan  1 00:00:00 1970
X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/7073
Path: news.gmane.org!not-for-mail
From: Rich Felker <dalias@libc.org>
Newsgroups: gmane.linux.lib.musl.general
Subject: Re: [PATCH] x86_64/memset: use "small block" code for blocks
 up to 30 bytes long
Date: Tue, 17 Feb 2015 16:12:47 -0500
Message-ID: <20150217211247.GI23507@brightrain.aerifal.cx>
References: <20150215040655.GM23507@brightrain.aerifal.cx>
 <CAK1hOcPQ=mADeAUP3i-Xt3rvHmgUrVVoz2yUEOkUEYQ2xRVN2g@mail.gmail.com>
 <20150215150313.GO23507@brightrain.aerifal.cx>
 <CAK1hOcMgM5j-EtOk2aPao6ma=M7PVyA_3U=22+8HbPu+S9GXdw@mail.gmail.com>
 <20150216173634.GA23507@brightrain.aerifal.cx>
 <CAK1hOcOEznkzfBGDJwWvdaNXTKwEiiz88r=9tEQF--T=CQvXJg@mail.gmail.com>
 <20150217161222.GF23507@brightrain.aerifal.cx>
 <CAK1hOcOaN4SnpO2jMGib3tFEf+c8=Tu8Nwi2YnOhzefpSSqTng@mail.gmail.com>
 <20150217174045.GH23507@brightrain.aerifal.cx>
 <CAK1hOcMtnZLy7Kw36YQWdi3tzmACepAWjQ=_82GuE_NUHd0hpw@mail.gmail.com>
Reply-To: musl@lists.openwall.com
NNTP-Posting-Host: plane.gmane.org
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Trace: ger.gmane.org 1424207592 6009 80.91.229.3 (17 Feb 2015 21:13:12 GMT)
X-Complaints-To: usenet@ger.gmane.org
NNTP-Posting-Date: Tue, 17 Feb 2015 21:13:12 +0000 (UTC)
Cc: musl <musl@lists.openwall.com>
To: Denys Vlasenko <vda.linux@googlemail.com>
Original-X-From: musl-return-7086-gllmg-musl=m.gmane.org@lists.openwall.com Tue Feb 17 22:13:10 2015
Return-path: <musl-return-7086-gllmg-musl=m.gmane.org@lists.openwall.com>
Envelope-to: gllmg-musl@m.gmane.org
Original-Received: from mother.openwall.net ([195.42.179.200])
	by plane.gmane.org with smtp (Exim 4.69)
	(envelope-from <musl-return-7086-gllmg-musl=m.gmane.org@lists.openwall.com>)
	id 1YNpS8-0002Br-Tx
	for gllmg-musl@m.gmane.org; Tue, 17 Feb 2015 22:13:09 +0100
Original-Received: (qmail 23783 invoked by uid 550); 17 Feb 2015 21:13:07 -0000
Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm
Precedence: bulk
List-Post: <mailto:musl@lists.openwall.com>
List-Help: <mailto:musl-help@lists.openwall.com>
List-Unsubscribe: <mailto:musl-unsubscribe@lists.openwall.com>
List-Subscribe: <mailto:musl-subscribe@lists.openwall.com>
Original-Received: (qmail 23684 invoked from network); 17 Feb 2015 21:13:00 -0000
Content-Disposition: inline
In-Reply-To: <CAK1hOcMtnZLy7Kw36YQWdi3tzmACepAWjQ=_82GuE_NUHd0hpw@mail.gmail.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
Original-Sender: Rich Felker <dalias@aerifal.cx>
Xref: news.gmane.org gmane.linux.lib.musl.general:7073
Archived-At: <http://permalink.gmane.org/gmane.linux.lib.musl.general/7073>

On Tue, Feb 17, 2015 at 07:53:28PM +0100, Denys Vlasenko wrote:
> On Tue, Feb 17, 2015 at 6:40 PM, Rich Felker <dalias@libc.org> wrote:
> >> With your program I see similar results:
> >>
> >> ....
> >> size 50: min=10, avg=10           min=10, avg=10
> >> size 52: min=10, avg=10           min=10, avg=10
> >
> > The ... was the part where mine seemed better. :)
> 
> Do you seriously think I would go as low as lying by omission?
> Here are the full, unabridged files of three runs of both algorithms.

No, that's not what I meant, and I'm sorry for making it sound that
way. I just meant it was the interesting part I wanted to compare. For
me, I get ~1 cycle difference for a number of the small runs, but on
your test that measures rates in a way that's probably more applicable
to real-world use, there was no measureable difference one way or the
other.

Rich