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Date: Tue, 18 Dec 2012 10:27:46 -0800
From: Arun Sharma <asharma@fb.com>
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To: Minchan Kim <minchan@kernel.org>
CC: Andrew Morton <akpm@linux-foundation.org>, <linux-kernel@vger.kernel.org>,
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Subject: Re: [RFC v4 0/3] Support volatile for anonymous range
References: <1355813274-571-1-git-send-email-minchan@kernel.org>
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On 12/17/12 10:47 PM, Minchan Kim wrote:

> I hope more inputs from user-space allocator people and test patch
> with their allocator because it might need design change of arena
> management for getting real vaule.

jemalloc knows how to handle MADV_FREE on platforms that support it. 
This looks similar (we'll need a SIGBUS handler that does the right 
thing = zero the page + mark it as non-volatile in the common case).

All of this of course assumes that apps madvise the kernel through APIs 
exposed by the malloc implementation - not via a raw syscall.

In other words, some new user space code needs to be written to test 
this out fully. Sounds feasible though.

  -Arun