From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pavel Emelyanov <xemul@parallels.com>
Subject: Re: [PATCH v3 3/4] limit nr_dentries per superblock
Date: Mon, 15 Aug 2011 16:12:55 +0400
Message-ID: <4E490D47.8050105@parallels.com>
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Cc: Dave Chinner <david@fromorbit.com>,
	Glauber Costa <glommer@parallels.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
	"containers@lists.linux-foundation.org"
	<containers@lists.linux-foundation.org>,
	Al Viro <viro@zeniv.linux.org.uk>,
	Hugh Dickins <hughd@google.com>,
	Nick Piggin <npiggin@kernel.dk>,
	Andrea Arcangeli <aarcange@redhat.com>,
	Rik van Riel <riel@redhat.com>,
	Dave Hansen <dave@linux.vnet.ibm.com>,
	James Bottomley <jbottomley@parallels.com>,
	Eric Dumazet <eric.dumazet@gmail.com>,
	Christoph Lameter <cl@linux.com>,
	David Rientjes <rientjes@google.com>
To: Pekka Enberg <penberg@kernel.org>
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On 08/15/2011 03:55 PM, Pekka Enberg wrote:
> On Mon, Aug 15, 2011 at 2:32 PM, Pavel Emelyanov <xemul@parallels.com> wrote:
>>> Couldn't you simply do per-container "struct kmem_accounted_cache" in struct superblock?
>>
>> If by this you mean "account for all the kmem associated with particular superblock" then
>> this is OK for us, but this can't be done in a simple
>>
>>        if (used + size > limit)
>>                return -ENOMEM
>>        else {
>>                used += size;
>>                return 0;
>>        }
>>
>> manner, since once we hit the limit we should shrink the unused dentries. And most of the
>> patches are about this.
> 
> So you want to shrink dentries that were allocated in the container
> that hit the dcache limit? How does this patch set deal with that? Or
> are you referring to some other patches?

Yes, this patchset does only the API part. The full idea is implemented (with poor API though) here:
http://lwn.net/Articles/441164/

>                          Pekka
> .
>