From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 30 Jul 2008 18:23:18 +0100 From: Mel Gorman Subject: Re: [RFC] [PATCH 0/5 V2] Huge page backed user-space stacks Message-ID: <20080730172317.GA14138@csn.ul.ie> References: <20080730014308.2a447e71.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20080730014308.2a447e71.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Eric Munson , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, libhugetlbfs-devel@lists.sourceforge.net List-ID: On (30/07/08 01:43), Andrew Morton didst pronounce: > On Mon, 28 Jul 2008 12:17:10 -0700 Eric Munson wrote: > > > Certain workloads benefit if their data or text segments are backed by > > huge pages. > > oh. As this is a performance patch, it would be much better if its > description contained some performance measurement results! Please. > I ran these patches through STREAM (http://www.cs.virginia.edu/stream/). STREAM itself was patched to allocate data from the stack instead of statically for the test. They completed without any problem on x86, x86_64 and PPC64 and each test showed a performance gain from using hugepages. I can post the raw figures but they are not currently in an eye-friendly format. Here are some plots of the data though; x86: http://www.csn.ul.ie/~mel/postings/stack-backing-20080730/x86-stream-stack.ps x86_64: http://www.csn.ul.ie/~mel/postings/stack-backing-20080730/x86_64-stream-stack.ps ppc64-small: http://www.csn.ul.ie/~mel/postings/stack-backing-20080730/ppc64-small-stream-stack.ps ppc64-large: http://www.csn.ul.ie/~mel/postings/stack-backing-20080730/ppc64-large-stream-stack.ps The test was to run STREAM with different array sizes (plotted on X-axis) and measure the average throughput (y-axis). In each case, backing the stack with large pages with a performance gain. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- 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