From mboxrd@z Thu Jan 1 00:00:00 1970 From: Diego Calleja Subject: Re: [RFC] VM: I have a dream... Date: Tue, 24 Jan 2006 16:04:27 +0100 Message-ID: <20060124160427.1ed68461.diegocg@gmail.com> References: <200601212108.41269.a1426z@gawab.com> <986ed62e0601221155x6a57e353vf14db02cc219c09@mail.gmail.com> <728201270601230705k25e6890ejd716dbfc393208b8@mail.gmail.com> <280A351A008C409CEF43A734@dhcp-2-206.wgops.com> <17365.23510.525066.57628@gargle.gargle.HOWL> <728201270601240636p58fead78m781fb104c3d73da9@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: nikita@clusterfs.com, mloftis@wgops.com, barryn@pobox.com, a1426z@gawab.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Return-path: Received: from uproxy.gmail.com ([66.249.92.206]:20097 "EHLO uproxy.gmail.com") by vger.kernel.org with ESMTP id S964991AbWAXPGC convert rfc822-to-8bit (ORCPT ); Tue, 24 Jan 2006 10:06:02 -0500 Received: by uproxy.gmail.com with SMTP id s2so145500uge for ; Tue, 24 Jan 2006 07:06:01 -0800 (PST) To: Ram Gupta In-Reply-To: <728201270601240636p58fead78m781fb104c3d73da9@mail.gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org El Tue, 24 Jan 2006 08:36:50 -0600, Ram Gupta escribi=F3: > This feature is interesting though I am not sure about the fast boot > part of OSX. > as at boot time these applications are all started first time. So > there were no access pattern as yet. They still have to be demand > paged. But yes later accesses may be faster. The stats are saved on disk (at least on windows). You don't really care about "later accesses" when everything is already in cache, this is supposed to speed up cold-cache startup. I don't know if mac os x does it for every app, the darwin code I saw was only for the startup of the system not for every app, but maybe that part was in another module Linux is the one desktop lacking something like this, both windows and max os x have things like this. I've wondered for long time if it's worth of it and if it could improve things in linux. The prefault part is easy once you get the data. The hard part is to get the statistics: I wonder if mincore(), /proc/$PID/maps=20 and the recently posted /proc/$PID/pmap and all the statistics the kernel can provide today are enought, or it's neccesary something more complex. - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html