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From: Satoru Moriya <satoru.moriya@hds.com>
To: Richard Davies <richard@arachsys.com>
CC: KOSAKI Motohiro <kosaki.motohiro@gmail.com>,
        Jerome Marchand <jmarchan@redhat.com>,
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        Seiji Aguchi <seiji.aguchi@hds.com>,
        Minchan Kim <minchan.kim@gmail.com>
Date: Tue, 24 Apr 2012 18:14:37 -0400
Subject: RE: [RFC][PATCH] avoid swapping out with swappiness==0
Thread-Topic: [RFC][PATCH] avoid swapping out with swappiness==0
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On 04/24/2012 04:20 AM, Richard Davies wrote:
> 
> I have run into problems with heavy swapping with swappiness==0 and 
> was pointed to this thread ( 
> http://marc.info/?l=linux-mm&m=133522782307215 )

Did you test this patch with your workload?
If yes, how did it come out?

> I strongly believe that Linux should have a way to turn off swapping 
> unless absolutely necessary. This means that users like us can run 
> with swap present for emergency use, rather than having to disable it 
> because of the side effects.

Agreed. That is why I proposed the patch.

> Personally, I feel that swappiness==0 should have this (intuitive) 
> meaning, and that people running RHEL5 are extremely unlikely to run 
> 3.5 kernels(!)
> 
> However, swappiness==-1 or some other hack is definitely better than 
> no patch.


Regards,
Satoru