From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id ABA7B6B0047 for ; Thu, 25 Feb 2010 18:42:51 -0500 (EST) Message-ID: <4B870AF1.90300@redhat.com> Date: Thu, 25 Feb 2010 18:42:41 -0500 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH 14/15] readahead: reduce MMAP_LOTSAMISS for mmap read-around References: <20100224031001.026464755@intel.com> <20100224031055.594006457@intel.com> In-Reply-To: <20100224031055.594006457@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Wu Fengguang Cc: Andrew Morton , Jens Axboe , Nick Piggin , Chris Mason , Peter Zijlstra , Clemens Ladisch , Olivier Galibert , Vivek Goyal , Christian Ehrhardt , Matt Mackall , Linux Memory Management List , linux-fsdevel@vger.kernel.org, LKML List-ID: On 02/23/2010 10:10 PM, Wu Fengguang wrote: > Now that we lifts readahead size from 128KB to 512KB, > the MMAP_LOTSAMISS shall be shrinked accordingly. > > We shrink it a bit more, so that for sparse random access patterns, > only 10*512KB or ~5MB memory will be wasted, instead of the previous > 100*128KB or ~12MB. The new threshold "10" is still big enough to avoid > turning off read-around for typical executable/lib page faults. > > CC: Nick Piggin > Signed-off-by: Wu Fengguang Acked-by: Rik van Riel -- 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