From owner-freebsd-current Mon Jan 20 00:06:26 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.4/8.8.4) id AAA18239 for current-outgoing; Mon, 20 Jan 1997 00:06:26 -0800 (PST) Received: from labinfo.iet.unipi.it (labinfo.iet.unipi.it [131.114.9.5]) by freefall.freebsd.org (8.8.4/8.8.4) with SMTP id AAA18231; Mon, 20 Jan 1997 00:06:17 -0800 (PST) Received: from localhost (luigi@localhost) by labinfo.iet.unipi.it (8.6.5/8.6.5) id IAA13617; Mon, 20 Jan 1997 08:22:29 +0100 From: Luigi Rizzo Message-Id: <199701200722.IAA13617@labinfo.iet.unipi.it> Subject: Re: possible madvise MADV_FREE improvement To: dyson@FreeBSD.ORG Date: Mon, 20 Jan 1997 08:22:28 +0100 (MET) Cc: dtc@scrooge.ee.swin.oz.au, current@FreeBSD.ORG In-Reply-To: <199701200206.VAA00126@dyson.iquest.net> from "John S. Dyson" at Jan 19, 97 09:05:47 pm X-Mailer: ELM [version 2.4 PL23] Content-Type: text Sender: owner-current@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk > > Below is a patch which seems to improve madvise MADV_FREE; stops the > > page-ins in the example recently posted. It also brings the call > > closer to reliably zeroing the pages. > > > Thanks for the bug report, and I will be committing a fix in a little > while (next hour or so) for the problem. Note that MADV_FREE does not > guarantee that the page will be zeroed in any way. Specificially, MADV_FREE > allows the system to optionally dispose of the contents of the page range, when does the system decide for disposing the pages, and wouldn't it be nice (and easy to implement) to have an option to force this behaviour ? Luigi -----------------------------+-------------------------------------- Luigi Rizzo | Dip. di Ingegneria dell'Informazione email: luigi@iet.unipi.it | Universita' di Pisa tel: +39-50-568533 | via Diotisalvi 2, 56126 PISA (Italy) fax: +39-50-568522 | http://www.iet.unipi.it/~luigi/ _____________________________|______________________________________