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* On shrinkable caches
@ 2016-06-20 11:26 Nikolay Borisov
  2016-06-23  9:43 ` David Sterba
  0 siblings, 1 reply; 3+ messages in thread
From: Nikolay Borisov @ 2016-06-20 11:26 UTC (permalink / raw)
  To: linux-btrfs; +Cc: clm, dsterba

Hello,

I have a question regarding the SLAB_RECLAIM_ACCOUNT flag with which
BTRFS caches are created. Currently there isn't a single usage of
register_shrinker under fs/btrfs. Apart from the inode cache which is
being shrunk from the generic super_cache_scan I don't think the memory
used for those caches should be accounted as reclaimable?

Regards,
Nikolay

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: On shrinkable caches
  2016-06-20 11:26 On shrinkable caches Nikolay Borisov
@ 2016-06-23  9:43 ` David Sterba
  2016-06-23 10:03   ` Nikolay Borisov
  0 siblings, 1 reply; 3+ messages in thread
From: David Sterba @ 2016-06-23  9:43 UTC (permalink / raw)
  To: Nikolay Borisov; +Cc: linux-btrfs, clm, dsterba

On Mon, Jun 20, 2016 at 02:26:12PM +0300, Nikolay Borisov wrote:
> I have a question regarding the SLAB_RECLAIM_ACCOUNT flag with which
> BTRFS caches are created. Currently there isn't a single usage of
> register_shrinker under fs/btrfs.

The SLAB_RECLAIM_ACCOUNT flag has been there since the first versions in
2007 (when shrinkeres did not exist) but I can't find any specific
reason why.

> Apart from the inode cache which is
> being shrunk from the generic super_cache_scan I don't think the memory
> used for those caches should be accounted as reclaimable?

I agree, in most cases I don't see any possibility to reclaim the
objects earlier than the explicit free.

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: On shrinkable caches
  2016-06-23  9:43 ` David Sterba
@ 2016-06-23 10:03   ` Nikolay Borisov
  0 siblings, 0 replies; 3+ messages in thread
From: Nikolay Borisov @ 2016-06-23 10:03 UTC (permalink / raw)
  To: dsterba, linux-btrfs, clm



On 06/23/2016 12:43 PM, David Sterba wrote:
> On Mon, Jun 20, 2016 at 02:26:12PM +0300, Nikolay Borisov wrote:
>> I have a question regarding the SLAB_RECLAIM_ACCOUNT flag with which
>> BTRFS caches are created. Currently there isn't a single usage of
>> register_shrinker under fs/btrfs.
> 
> The SLAB_RECLAIM_ACCOUNT flag has been there since the first versions in
> 2007 (when shrinkeres did not exist) but I can't find any specific
> reason why.
> 
>> Apart from the inode cache which is
>> being shrunk from the generic super_cache_scan I don't think the memory
>> used for those caches should be accounted as reclaimable?
> 
> I agree, in most cases I don't see any possibility to reclaim the
> objects earlier than the explicit free.

If that's the case, then I'll be happy to send a patch.


^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2016-06-23 10:03 UTC | newest]

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