From mboxrd@z Thu Jan  1 00:00:00 1970
From: Boaz Harrosh <bharrosh@panasas.com>
Subject: Re: [LSF/MM TOPIC] Parallelize file operation (like creation, unlink)
 under large shared directory
Date: Sun, 22 Jan 2012 15:55:34 +0200
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To: wangdi <di.wang@whamcloud.com>
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On 01/21/2012 10:54 PM, wangdi wrote:
> 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.
> 

read NFSD here ;-)

> 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.
> 

I agree about create, unlink, and so on. But don't we have some lockless
look up in place since a few Kernels ago?

But yes the topic is very interesting, though I'd suspect its hard to
implement.

> Thanks
> WangDi
> 

Thanks
Boaz