From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <42C09AB3.7030907@yahoo.com.au> Date: Tue, 28 Jun 2005 10:32:51 +1000 From: Nick Piggin MIME-Version: 1.0 Subject: Re: [rfc] lockless pagecache References: <42BF9CD1.2030102@yahoo.com.au> <20050627004624.53f0415e.akpm@osdl.org> <42BFB287.5060104@yahoo.com.au> <20050627131710.GC13945@kvack.org> In-Reply-To: <20050627131710.GC13945@kvack.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Benjamin LaHaise Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: Benjamin LaHaise wrote: > On Mon, Jun 27, 2005 at 06:02:15PM +1000, Nick Piggin wrote: > >>However I think for Oracle and others that use shared memory like >>this, they are probably not doing linear access, so that would be a >>net loss. I'm not completely sure (I don't have access to real loads >>at the moment), but I would have thought those guys would have looked >>into fault ahead if it were a possibility. > > > Shared memory overhead doesn't show up on any of the database benchmarks > I've seen, as they tend to use huge pages that are locked in memory, and > thus don't tend to access the page cache at all after ramp up. > To be quite honest I don't have any real workloads here that stress it, however I was told that it is a problem for oracle database. If there is anyone else who has problems then I'd be interested to hear them as well. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com -- 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: aart@kvack.org