Messages in this thread | | | Date | Tue, 15 Jun 2010 10:11:37 +0300 | From | Avi Kivity <> | Subject | Re: [RFC/T/D][PATCH 2/2] Linux/Guest cooperative unmapped page cache control |
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On 06/14/2010 08:40 PM, Balbir Singh wrote: > * Avi Kivity<avi@redhat.com> [2010-06-14 18:34:58]: > > >> On 06/14/2010 06:12 PM, Dave Hansen wrote: >> >>> On Mon, 2010-06-14 at 14:18 +0530, Balbir Singh wrote: >>> >>>> 1. A slab page will not be freed until the entire page is free (all >>>> slabs have been kfree'd so to speak). Normal reclaim will definitely >>>> free this page, but a lot of it depends on how frequently we are >>>> scanning the LRU list and when this page got added. >>>> >>> You don't have to be freeing entire slab pages for the reclaim to have >>> been useful. You could just be making space so that _future_ >>> allocations fill in the slab holes you just created. You may not be >>> freeing pages, but you're reducing future system pressure. >>> >> Depends. If you've evicted something that will be referenced soon, >> you're increasing system pressure. >> >> > I don't think slab pages care about being referenced soon, they are > either allocated or freed. A page is just a storage unit for the data > structure. A new one can be allocated on demand. >
If we're talking just about slab pages, I agree. If we're applying pressure on the shrinkers, then you are removing live objects which can be costly to reinstantiate.
-- error compiling committee.c: too many arguments to function
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