From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 7 Jun 2000 16:09:31 +0200 From: Jamie Lokier Subject: Re: [PATCH] VM kswapd autotuning vs. -ac7 Message-ID: <20000607160931.C22749@pcep-jamie.cern.ch> References: <20000607143242.D30951@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20000607143242.D30951@redhat.com>; from sct@redhat.com on Wed, Jun 07, 2000 at 02:32:42PM +0100 Sender: owner-linux-mm@kvack.org Return-Path: To: "Stephen C. Tweedie" Cc: Christoph Rohland , Rik van Riel , linux-mm@kvack.org List-ID: Stephen C. Tweedie wrote: > The main reason SHM needs its own swap code is that normal anonymous > pages are referred to only from ptes --- the ptes either point to > the physical page containing the page, or to the swap entry. We > cannot use that for SHM, because SysV SHM segments must be persistent > even if there are no attachers, and hence no ptes to maintain the > location of the pages. It might be possible to create MMs without tasks specifically to map the SHM segments. -- Jamie -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux.eu.org/Linux-MM/