From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Cox Subject: Re: [RFC] VM: I have a dream... Date: Thu, 02 Feb 2006 15:11:29 +0000 Message-ID: <1138893090.9861.25.camel@localhost.localdomain> References: <200601301621.24051.a1426z@gawab.com> <8F530CA8-1AC8-4AE5-8F1E-DC6518BD7D42@mac.com> <200601311856.17569.a1426z@gawab.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Kyle Moffett , Bryan Henderson , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:40076 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S1751123AbWBBPKS (ORCPT ); Thu, 2 Feb 2006 10:10:18 -0500 To: Al Boldi In-Reply-To: <200601311856.17569.a1426z@gawab.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Maw, 2006-01-31 at 18:56 +0300, Al Boldi wrote: > So with 64bits widely available now, and to let Linux spread its wings and > really fly, how could tmpfs merged w/ swap be tweaked to provide direct > mapped access into this linear address space? Why bother. You can already create a private large file and mmap it if you want to do this, and you will get better performance than being smeared around swap with everyone else. Currently swap means your data is mixed in with other stuff. Swap could do preallocation of each vma when running in limited overcommit modes and it would run a lot faster if you did but you would pay a lot in flexibility and efficiency, as well as needing a lot more swap. Far better to let applications wanting to work this way do it themselves. Just mmap and the cache balancing and pager will do the rest for you.