From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 25 Feb 2008 15:07:24 +0000 From: Andy Whitcroft Subject: Re: Page scan keeps touching kernel text pages Message-ID: <20080225150724.GF2604@shadowen.org> References: <20080224144710.GD31293@lazybastard.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20080224144710.GD31293@lazybastard.org> Sender: owner-linux-mm@kvack.org Return-Path: To: =?iso-8859-1?Q?J=F6rn?= Engel Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On Sun, Feb 24, 2008 at 03:47:11PM +0100, Jorn Engel wrote: > While tracking down some unrelated bug I noticed that shrink_page_list() > keeps testing very low page numbers (aka kernel text) until deciding > that the page lacks a mapping and cannot get freed. Looks like a waste > of cpu and cachelines to me. > > Is there a better reason for this behaviour than lack of a patch? shrink_page_list() would be expected to be passed pages pulled from the active or inactive lists via isolate_lru_pages()? I would not have expected to find the kernel text on the LRU and therefore not expect to see it passed to shrink_page_list()? I would expect to find pages below the kernel text as real pages, and potentially on the LRU on some architectures. Which architecture are you seeing this? Which zones do the pages belong? -apw -- 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-mm.org/ . Don't email: email@kvack.org