From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rik van Riel <riel@redhat.com>
Subject: Re: [PATCH 2/3] fs/superblock: Avoid locking counting inodes and
 dentries before reclaiming them
Date: Thu, 22 May 2014 11:59:34 -0400
Message-ID: <537E1EE6.8080102@redhat.com>
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Cc: Johannes Weiner <hannes@cmpxchg.org>,
	Hugh Dickins <hughd@google.com>,
	Tim Chen <tim.c.chen@linux.intel.com>,
	Dave Chinner <david@fromorbit.com>,
	Yuanhan Liu <yuanhan.liu@linux.intel.com>,
	Bob Liu <bob.liu@oracle.com>, Jan Kara <jack@suse.cz>,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	Linux-MM <linux-mm@kvack.org>,
	Linux-FSDevel <linux-fsdevel@vger.kernel.org>
To: Mel Gorman <mgorman@suse.de>,
	Andrew Morton <akpm@linux-foundation.org>
Return-path: <linux-fsdevel-owner@vger.kernel.org>
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On 05/22/2014 05:09 AM, Mel Gorman wrote:
> From: Tim Chen <tim.c.chen@linux.intel.com>
> 
> We remove the call to grab_super_passive in call to super_cache_count.
> This becomes a scalability bottleneck as multiple threads are trying to do
> memory reclamation, e.g. when we are doing large amount of file read and
> page cache is under pressure.  The cached objects quickly got reclaimed
> down to 0 and we are aborting the cache_scan() reclaim.  But counting
> creates a log jam acquiring the sb_lock.

> Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
> Signed-off-by: Mel Gorman <mgorman@suse.de>

Acked-by: Rik van Riel <riel@redhat.com>


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