Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752165AbYKRKHa (ORCPT ); Tue, 18 Nov 2008 05:07:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751361AbYKRKHV (ORCPT ); Tue, 18 Nov 2008 05:07:21 -0500 Received: from smtp119.mail.mud.yahoo.com ([209.191.84.76]:33373 "HELO smtp119.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751356AbYKRKHV (ORCPT ); Tue, 18 Nov 2008 05:07:21 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:X-YMail-OSG:X-Yahoo-Newman-Property:From:To:Subject:Date:User-Agent:Cc:References:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-Disposition:Message-Id; b=3XhkeHuCiqcpX3uxPFYXDZw/KlI1SlJt67LVHkZl98CPWQKf7nYOe4RQCyQ7jkkE2M26sZuYxPEOspe3JoBeNUUzRi148lIkODshJK9vrc3DDW74JuXpZGgXNT8lwkA0PS6lJXzJmkCYPVXtyuW+t/RxXlPGCk2ppYKvHroexvc= ; X-YMail-OSG: xcQodJ4VM1k1mM7OsHTEJSQTC78vvQKIK0XMQwDTcLCtJToS8TXikkWYPJqGpRmXtXNndzF1F0srT0HC5KwUXfkuL783dO0YQbqDwk5a.oDXaKqNZnRDm1lmFDQOrFYbnUO3ycEiIaVaHEfJt7paMJyXLt.t1GuJ6SgMt9MW X-Yahoo-Newman-Property: ymail-3 From: Nick Piggin To: Paul Mackerras Subject: Re: Large stack usage in fs code (especially for PPC64) Date: Tue, 18 Nov 2008 21:07:12 +1100 User-Agent: KMail/1.9.5 Cc: Linus Torvalds , Steven Rostedt , LKML , Benjamin Herrenschmidt , linuxppc-dev@ozlabs.org, Andrew Morton , Ingo Molnar , Thomas Gleixner References: <18721.62958.479215.822513@cargo.ozlabs.ibm.com> In-Reply-To: <18721.62958.479215.822513@cargo.ozlabs.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200811182107.12747.nickpiggin@yahoo.com.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 877 Lines: 19 On Tuesday 18 November 2008 09:53, Paul Mackerras wrote: > I'd love to be able to use a 4k base page size if I could still get > the reduction in page faults and the expanded TLB reach that we get > now with 64k pages. If we could allocate the page cache for large > files with order-4 allocations wherever possible that would be a good > start. That can still have nasty side-effects like fragmentation and 64k granular reclaim. It also adds complexity to mapping the pages to userspace. Christoph's patchset IIRC also only did page cache, wheras I suppose your kernbench workload is gaining mainly from anonymous page faults. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/