From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with SMTP id 635D56B01EE for ; Mon, 12 Apr 2010 04:34:28 -0400 (EDT) Date: Mon, 12 Apr 2010 18:34:20 +1000 From: Nick Piggin Subject: Re: hugepages will matter more in the future Message-ID: <20100412083420.GV5683@laptop> References: <20100411110015.GA10149@elte.hu> <4BC1B034.4050302@redhat.com> <20100411115229.GB10952@elte.hu> <4BC1EE13.7080702@redhat.com> <4BC1F31E.2050009@redhat.com> <20100412074557.GA18485@elte.hu> <20100412081431.GT5683@laptop> <20100412082218.GA7380@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100412082218.GA7380@elte.hu> Sender: owner-linux-mm@kvack.org To: Ingo Molnar Cc: Avi Kivity , Linus Torvalds , Jason Garrett-Glaser , Mike Galbraith , Andrea Arcangeli , Pekka Enberg , Andrew Morton , linux-mm@kvack.org, Marcelo Tosatti , Adam Litke , Izik Eidus , Hugh Dickins , Rik van Riel , Mel Gorman , Dave Hansen , Benjamin Herrenschmidt , Mike Travis , KAMEZAWA Hiroyuki , Christoph Lameter , Chris Wright , bpicco@redhat.com, KOSAKI Motohiro , Balbir Singh , Arnd Bergmann , "Michael S. Tsirkin" , Peter Zijlstra , Johannes Weiner , Daisuke Nishimura , Arjan van de Ven List-ID: On Mon, Apr 12, 2010 at 10:22:18AM +0200, Ingo Molnar wrote: > > * Nick Piggin wrote: > > > > 2) or we accept the fact that the application space is shifting to the > > > meta-kernels - and then we should agressively optimize Linux for those > > > meta-kernels and not pretend that they are 'specialized'. They literally > > > represent tens of thousands of applications apiece. > > > > And if meta-kernels (or whatever you want to call a common or important > > workload) see some speedup that is deemed to be worth the cost of the patch, > > then it will probably get merged. Same as anything else. > > I call a 'meta kernel' something that people code thousands of apps for, > instead of coding on the native kernel. JVM/DBs/Firefox are such frameworks. > (you can call it middleware i guess) > > By all means they are not a 'single special-purpose workload' but represent > literally tens of thousands of apps. I don't think I said anything like 'single special-purpose workload'. I said 'common or important workload'. And they are not fundamentally different (in context of evaluating and accepting a performance improvement) than any other workload. I'm not saying they don't matter. The interesting fact is also that such type of thing is also much more suitable for doing optimisation tricks. JVMs and RDBMS typically can make use of hugepages already, for example. -- 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