From mboxrd@z Thu Jan  1 00:00:00 1970
From: wangdi <di.wang@whamcloud.com>
Subject: [LSF/MM TOPIC] Parallelize file operation (like creation, unlink)
 under large shared directory
Date: Sat, 21 Jan 2012 12:54:42 -0800
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Cc: linux-fsdevel@vger.kernel.org,
	Jinshan Xiong <jinshan.xiong@whamcloud.com>
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Single directory performance is a critical in some use cases. For 
example the multiple application threads might create hundreds of 
thousands of files in a single directory simultaneously within a short 
window of time.

Currently, both filename lookup and file system modifying operations 
(such as create and unlink) are protected with a single lock for the 
entire directory. It might be useful to remove this lock, so multiple 
application threads can access the directory simultaneously.

Thanks
WangDi