From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id 9B8777F4E for ; Tue, 24 Sep 2013 09:04:42 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay1.corp.sgi.com (Postfix) with ESMTP id 5F3738F8050 for ; Tue, 24 Sep 2013 07:04:39 -0700 (PDT) Received: from aserp1040.oracle.com (aserp1040.oracle.com [141.146.126.69]) by cuda.sgi.com with ESMTP id vU4kENamFM42HCEN (version=TLSv1 cipher=AES256-SHA bits=256 verify=NO) for ; Tue, 24 Sep 2013 07:04:38 -0700 (PDT) Message-ID: <52419C20.8040105@oracle.com> Date: Tue, 24 Sep 2013 22:05:20 +0800 From: Jeff Liu MIME-Version: 1.0 Subject: Re: [PATCH] xfs: improve xfs_iext_destroy() by freeing extent indirection array directly References: <523C5E92.8000406@oracle.com> <20130923003617.GM12541@dastard> <523FCA18.1000204@oracle.com> <20130923235017.GX9901@dastard> In-Reply-To: <20130923235017.GX9901@dastard> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: "xfs@oss.sgi.com" On 09/24/2013 07:50 AM, Dave Chinner wrote: > On Mon, Sep 23, 2013 at 12:56:56PM +0800, Jeff Liu wrote: >> On 09/23/2013 08:36 AM, Dave Chinner wrote: >> >>> On Fri, Sep 20, 2013 at 10:41:22PM +0800, Jeff Liu wrote: >>>> From: Jie Liu >>>> >>>> To free the incore file extents stores at the indirection array, we >>>> call the common routine xfs_iext_irec_remove() to remove a record >>>> from the array one at a time in reverse order, which will resize an >>>> extent indirection array repeatedly according to the array size. >>>> >>>> This is not often the case to make a file with thousands extent records >>>> stores at an indirection array, but above operation is inefficient and >>>> could result in memory fragments. >>> >>> Yes, it may be inefficient, but I don't see that it's a contributor >>> to memory fragmentation as the reallocated buffer is freed shortly >>> after it has been allocated as the array shrinks. Do you have any >>> evidence to suggest that such behaviour is actually fragmenting >>> memory? If so, is the any test case that reproduces this problem? >> >> Ah, yes, it should not cause memory fragmentation. >> >> The benefits is that this change could save alloc/free buffers depending >> on the number of extents records are stored at indirection array. > > OK, can you send a new version with an updated commit message? Sure, will post it soon. Thanks, -Jeff _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs