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Date: Wed, 15 Sep 2010 23:11:58 +0530
From: Balbir Singh <balbir@linux.vnet.ibm.com>
To: Richard Guenther <rguenther@suse.de>
Cc: Nikanth Karthikesan <knikanth@suse.de>,
        KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>, linux-mm@kvack.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Michael Matz <matz@novell.com>, Matt Mackall <mpm@selenic.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] After swapout/swapin private dirty mappings are
 reported clean in smaps
Message-ID: <20100915174157.GA22371@balbir.in.ibm.com>
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* Richard Guenther <rguenther@suse.de> [2010-09-15 16:14:17]:

> On Wed, 15 Sep 2010, Balbir Singh wrote:
> 
> > * Nikanth Karthikesan <knikanth@suse.de> [2010-09-15 12:01:11]:
> > 
> > > How? Current smaps information without this patch provides incorrect 
> > > information. Just because a private dirty page became part of swap cache, it 
> > > shown as clean and backed by a file. If it is shown as clean and backed by 
> > > swap then it is fine.
> > >
> > 
> > How is GDB using this information?  
> 
> GDB counts the number of dirty and swapped pages in a private mapping and
> based on that decides whether it needs to dump it to a core file or not.
> If there are no dirty or swapped pages gdb assumes it can reconstruct
> the mapping from the original backing file.  This way for example
> shared libraries do not end up in the core file.
>

Thanks for clarifying 

-- 
	Three Cheers,
	Balbir