From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from icarus.com (icarus.icarus.com [64.105.89.2]) by ozlabs.org (Postfix) with ESMTP id 837A267A79 for ; Sat, 19 Feb 2005 05:58:46 +1100 (EST) Received: from [192.168.1.7] (wing [192.168.1.7]) (authenticated) by icarus.com (8.11.6/8.11.6) with ESMTP id j1IIwiA04235 for ; Fri, 18 Feb 2005 10:58:44 -0800 Message-ID: <42163AE4.1090503@icarus.com> Date: Fri, 18 Feb 2005 10:58:44 -0800 From: Stephen Williams MIME-Version: 1.0 To: linuxppc-embedded@ozlabs.org References: <42152ADD.8040104@icarus.com> <20050218004327.GB10915@gate.ebshome.net> <20050218005905.GC10915@gate.ebshome.net> In-Reply-To: <20050218005905.GC10915@gate.ebshome.net> Content-Type: text/plain; charset=us-ascii; format=flowed Subject: Re: Linux processes, tempfs and programs List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Eugene Surovegin wrote: | On Thu, Feb 17, 2005 at 04:43:27PM -0800, Eugene Surovegin wrote: | |>On Thu, Feb 17, 2005 at 03:38:05PM -0800, Stephen Williams wrote: |>>But if I do that, I want to remove the program from the directory |>>after I start it, so that the file does not take up ram space. Will |>>that actually work? I'm using exec(2) to execute the program file |>>wherever it is downloaded. Will a subsequent unlink of the file |>>have a result, or will the file continue to take up space as |>>backing store for the executable? |>I think unlink will remove the file from directory (so you won't be |>able to see it with ls), but it will still continue to to take space - |>you're right it will be used as backing store, at least for read-only |>segments, which can be discarded if memory is tight. Even if you mlock |>all executable in memory, I think there will be still at least one |>reference to this file, which will prevent freeing tmpfs memory. | | | A little correction, according to tmpfs doc, it lives completely in | page cache, so I think memory is not wasted for unmodified sections of | the loaded file (e.g. a second copy, when file is executed and loaded | into user-space, isn't being made). | | But as usual, make some measurements first :) So far as I can see in my simplistic tests, this still takes twice as much memory as leaving the executable on a disk somewhere. This seems to be an inevitable consequence of execve on Linux 2.4.x. That's a bummer. Any other suggestions? - -- Steve Williams "The woods are lovely, dark and deep. steve at icarus.com But I have promises to keep, http://www.icarus.com and lines to code before I sleep, http://www.picturel.com And lines to code before I sleep." -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.5 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFCFjrjrPt1Sc2b3ikRAjwvAKCogiZ5i+OHdsGskhsfC97+jxl/ygCgqAql P77LUWxMW87T7ReXVg27fj8= =j9KI -----END PGP SIGNATURE-----