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Subject: RE: [PATCH 2/5] vmevent: Convert from deferred timer to deferred
 work
Thread-Topic: [PATCH 2/5] vmevent: Convert from deferred timer to deferred
 work
Thread-Index: AQHNP/HM8KMmZkc4xkKq2ZDXaeCP2Zbvq0sAgAA7gACAACLOoP//4JWAgAAi/oD//+B6AIAAIckQ
Date: Fri, 8 Jun 2012 07:28:18 +0000
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> -----Original Message-----
> From: ext KOSAKI Motohiro [mailto:kosaki.motohiro@gmail.com]
> Sent: 08 June, 2012 10:23
...
> > If you wakeup only by signal when memory situation changed you can be
> not mlocked.
> > Mlocking uses memory very inefficient way and usually cannot be applied
> for apps which wants to be notified due to resources restrictions.
> 
> That's your choice. If you don't need to care cache dropping, We don't
> enforce it. I only pointed out your explanation was technically incorrect.

My explanation is correct. That is an overhead you have to pay if start to use API based on polling from user-space and this overhead narrows API applicability.
Moving all times/tracking to kernel avoid useless wakeups in user-space.