From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff King Subject: Re: [PATCH 0/5] Suggested for PU: revision caching system to significantly speed up packing/walking Date: Sat, 8 Aug 2009 03:30:42 -0400 Message-ID: <20090808073042.GA20951@coredump.intra.peff.net> References: <4A7B95A8.2010000@vilain.net> <7vzlabp7e4.fsf@alter.siamese.dyndns.org> <7vfxc3ov8t.fsf@alter.siamese.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: Junio C Hamano , Nicolas Pitre , Johannes Schindelin , Sam Vilain , Michael J Gruber , "Shawn O. Pearce" , Andreas Ericsson , Christian Couder , "git@vger.kernel.org" To: Nick Edelen X-From: git-owner@vger.kernel.org Sat Aug 08 09:30:51 2009 Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1MZgOB-0007Hy-FC for gcvg-git-2@gmane.org; Sat, 08 Aug 2009 09:30:51 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754465AbZHHHao (ORCPT ); Sat, 8 Aug 2009 03:30:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754460AbZHHHao (ORCPT ); Sat, 8 Aug 2009 03:30:44 -0400 Received: from peff.net ([208.65.91.99]:45606 "EHLO peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754453AbZHHHan (ORCPT ); Sat, 8 Aug 2009 03:30:43 -0400 Received: (qmail 23999 invoked by uid 107); 8 Aug 2009 07:32:56 -0000 Received: from coredump.intra.peff.net (HELO coredump.intra.peff.net) (10.0.0.2) by peff.net (qpsmtpd/0.40) with (AES128-SHA encrypted) SMTP; Sat, 08 Aug 2009 03:32:56 -0400 Received: by coredump.intra.peff.net (sSMTP sendmail emulation); Sat, 08 Aug 2009 03:30:42 -0400 Content-Disposition: inline In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On Sat, Aug 08, 2009 at 09:27:55AM +0200, Nick Edelen wrote: > > IIRC from previous discussions, kernel.org's main performance problem is > > I/O, not CPU. Are there any provisions for sharing rev-caches between > > similar repositories, as we already do for objects? > > I haven't implemented a transmission protocol or anything, but it > would be perfectly possible to copy cache slices from one repo to > another. Generating the revision cache from scratch on large repos > can take several minutes, so this wouldn't be a bad idea. That might be useful, but I was thinking more of an "alternates"-like mechanism between repos. So that the data is stored only once on disk and in the disk cache, which is helpful for sites like kernel.org which serve many similar repositories. -Peff