From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nick Piggin Subject: Re: kswapd min order, slub max order [was Re: -mm merge plans for 2.6.24] Date: Tue, 2 Oct 2007 19:10:58 +1000 References: <20071001142222.fcaa8d57.akpm@linux-foundation.org> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200710021910.58983.nickpiggin@yahoo.com.au> Sender: owner-linux-mm@kvack.org Return-Path: To: Hugh Dickins Cc: Andrew Morton , Chritoph Lameter , Mel Gorman , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Wednesday 03 October 2007 02:06, Hugh Dickins wrote: > On Mon, 1 Oct 2007, Andrew Morton wrote: > > # > > # slub && antifrag > > # > > have-kswapd-keep-a-minimum-order-free-other-than-order-0.patch > > only-check-absolute-watermarks-for-alloc_high-and-alloc_harder-allocation > >s.patch slub-exploit-page-mobility-to-increase-allocation-order.patch > > slub-reduce-antifrag-max-order.patch > > > > I think this stuff is in the "mm stuff we don't want to merge" > > category. If so, I really should have dropped it ages ago. > > I agree. I spent a while last week bisecting down to see why my heavily > swapping loads take 30%-60% longer with -mm than mainline, and it was > here that they went bad. Trying to keep higher orders free is costly. Yeah, no there's no way we'd merge that. > On the other hand, hasn't SLUB efficiency been built on the expectation > that higher orders can be used? And it would be a twisted shame for > high performance to be held back by some idiot's swapping load. IMO it's a bad idea to create all these dependencies like this. If SLUB can get _more_ performance out of using higher order allocations, then fine. If it is starting off at a disadvantage at the same order, then it that should be fixed first, right? -- 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