From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gir.skynet.ie (gir.skynet.ie [193.1.99.77]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id E779CDDE1D for ; Thu, 29 Nov 2007 03:12:09 +1100 (EST) Date: Wed, 28 Nov 2007 16:12:02 +0000 From: Mel Gorman To: Arnd Bergmann Subject: Re: [PATCH 1/2] powerpc: add hugepagesz boot-time parameter Message-ID: <20071128161201.GA10916@csn.ul.ie> References: <474CF68E.1040709@us.ibm.com> <200711280826.46820.arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 In-Reply-To: <200711280826.46820.arnd@arndb.de> Cc: linuxppc-dev@ozlabs.org, kniht@linux.vnet.ibm.com, Linux Memory Management List List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On (28/11/07 08:26), Arnd Bergmann didst pronounce: > On Wednesday 28 November 2007, Jon Tollefson wrote: > > This patch adds the hugepagesz boot-time parameter for ppc64 that lets > > you pick the size for your huge pages.  The choices available are 64K > > and 16M.  It defaults to 16M (previously the only choice) if nothing or > > an invalid choice is specified.  Tested 64K huge pages with the > > libhugetlbfs 1.2 release with its 'make func' and 'make stress' test > > invocations. > > How hard would it be to add the 1MB page size that some CPUs support > as well? On systems with small physical memory like the PS3, that > sounds very useful to me. > Does the PS3 support 1M pages in hardware? When I last looked, the magic ibm,segment-page-sizes file that described the supported pagesizes was missing from the device tree. In this situation, the default sizes become 4K and 16M because no other ones are advertised. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab