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Date: Tue, 24 Jun 2014 14:59:37 -0700 (PDT)
From: David Rientjes <rientjes@google.com>
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To: Maksym Planeta <mcsim.planeta@gmail.com>
cc: Alexander Viro <viro@zeniv.linux.org.uk>,
        Thomas Knauth <thomas.knauth@gmx.de>, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sysctl: Add a feature to drop caches selectively
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On Tue, 24 Jun 2014, Maksym Planeta wrote:

> To clean the page cache one can use /proc/sys/vm/drop_caches. But this
> drops the whole page cache. In contrast to that sdrop_caches enables
> ability to drop the page cache selectively by path string.
> 
> Suggested-by: Thomas Knauth <thomas.knauth@gmx.de>
> Signed-off-by: Maksym Planeta <mcsim.planeta@gmail.com>

Could you include some information in the commit message about why this is 
useful?  Specifically, why you want to drop pagecache only from a specific 
path.

The name of the sysctl is also quite non-descriptive.