From mboxrd@z Thu Jan 1 00:00:00 1970 From: Fredrik Gustafsson Subject: Re: [PATCH v2 0/5] New hash table implementation Date: Thu, 26 Sep 2013 13:08:18 +0200 Message-ID: <20130926110818.GE6615@paksenarrion.iveqy.com> References: <522FAAC4.2080601@gmail.com> <52416058.90008@gmail.com> <20130926101648.GD6615@paksenarrion.iveqy.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Fredrik Gustafsson , Karsten Blees , Git List To: Duy Nguyen X-From: git-owner@vger.kernel.org Thu Sep 26 13:00:41 2013 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1VP9JJ-0008Qo-2M for gcvg-git-2@plane.gmane.org; Thu, 26 Sep 2013 13:00:41 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756469Ab3IZLAh convert rfc822-to-quoted-printable (ORCPT ); Thu, 26 Sep 2013 07:00:37 -0400 Received: from mail-la0-f53.google.com ([209.85.215.53]:52906 "EHLO mail-la0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756019Ab3IZLAg (ORCPT ); Thu, 26 Sep 2013 07:00:36 -0400 Received: by mail-la0-f53.google.com with SMTP id el20so794945lab.12 for ; Thu, 26 Sep 2013 04:00:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=PUZjipwVyfgxWUOckEqy9Usxi1QnNGVNfjCczf1Ft6g=; b=aOipcekXDDSHV69uCEVu7evpWm7j7Txu2MxsYMszMaAE8x7UcLrOkoCpWVNqilV7Ja szX5F+CEw21y9IJSrTWFEOxSTVdIg3WTAG9Zbi8ZjRcn0PFAXBcxUb0unXj0hz1xIqaq hP/75SbkNNMcnvt/RT29/oOGDQYU65cCYpqIzJO94/7QrQtqj6PSoHNc0yP0oOAMFSEq 3Su+VUjPCbo+Pus4wM1eoakEgOd/nzRQ2Y/spJ4vzcfzcI+0u4CXWAqvFHhJ+yUboAo2 xla7uGUm4/j9rDK4RBXo/m+/I8It81luZp7beNe98A4ESJIN+NKCHkU4dqU+sk1pnylx zB3w== X-Received: by 10.152.228.130 with SMTP id si2mr230165lac.32.1380193235083; Thu, 26 Sep 2013 04:00:35 -0700 (PDT) Received: from paksenarrion.iveqy.com (c83-250-237-167.bredband.comhem.se. [83.250.237.167]) by mx.google.com with ESMTPSA id yl7sm2030913lbb.0.1969.12.31.16.00.00 (version=TLSv1 cipher=RC4-SHA bits=128/128); Thu, 26 Sep 2013 04:00:34 -0700 (PDT) Received: from iveqy by paksenarrion.iveqy.com with local (Exim 4.72) (envelope-from ) id 1VP9Qg-0000hD-FL; Thu, 26 Sep 2013 13:08:18 +0200 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On Thu, Sep 26, 2013 at 05:26:27PM +0700, Duy Nguyen wrote: > On Thu, Sep 26, 2013 at 5:16 PM, Fredrik Gustafsson = wrote: > > On Tue, Sep 24, 2013 at 11:50:16AM +0200, Karsten Blees wrote: > >> Tests can be reproduced with 'time echo "perfhash[map] 10= 00" | ./test-hashmap', see test-hashmap.c for definition of method flag= s. > > > > So I'm still curious about the actual performance improvements for = git. > > I runned git describe on the linux kernel with both the old hashmap= and > > this new one: > > > > ... > > > > I can't see any improvements at all here. What do I miss? Am I runn= ing > > git describe in the wrong way? Does linux.git have too few tags to = be > > important? >=20 > I wonder if it makes any difference if there are a lot more refs. I > hear gerrit creates a lot but don't know how many. linux-2.6 has ~350 > refs. How about increasing the number of refs to 3500 refs? So I runned: for i in $(git rev-list HEAD ); do git tag "tag$i" $i ; done in my linux repo and aborted it after a while: iveqy@minilla:/srv/slask/linux$ git tag | wc -l 9323 So it's a few at least. Not sure how those artificial tagnames would hurt or improve the performance. Old hashtable =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D iveqy@minilla:/srv/slask/linux$ time ../git/git describe HEAD=20 v3.12-rc2-83-g4b97280 real 0m0.384s user 0m0.288s sys 0m0.092s iveqy@minilla:/srv/slask/linux$ time ../git/git describe HEAD=20 v3.12-rc2-83-g4b97280 real 0m0.383s user 0m0.284s sys 0m0.100s iveqy@minilla:/srv/slask/linux$ time ../git/git describe HEAD=20 v3.12-rc2-83-g4b97280 real 0m0.386s user 0m0.312s sys 0m0.072s New hashtable =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D iveqy@minilla:/srv/slask/linux$ time ../git/git describe HEAD=20 v3.12-rc2-83-g4b97280 real 0m0.382s user 0m0.300s sys 0m0.084s iveqy@minilla:/srv/slask/linux$ time ../git/git describe HEAD=20 v3.12-rc2-83-g4b97280 real 0m0.382s user 0m0.288s sys 0m0.092s iveqy@minilla:/srv/slask/linux$ time ../git/git describe HEAD=20 v3.12-rc2-83-g4b97280 real 0m0.384s user 0m0.296s sys 0m0.088s --=20 Med v=E4nliga h=E4lsningar =46redrik Gustafsson tel: 0733-608274 e-post: iveqy@iveqy.com