Re: [patch 7/7] mm: reduce rmap overhead for ex-KSM page copies created on swap faults

2012-12-19 Thread Johannes Weiner
On Wed, Dec 19, 2012 at 02:01:19AM -0500, Simon Jeons wrote: > On Mon, 2012-12-17 at 13:12 -0500, Johannes Weiner wrote: > > When ex-KSM pages are faulted from swap cache, the fault handler is > > not capable of re-establishing anon_vma-spanning KSM pages. In this > > case, a copy of the page is

Re: [patch 7/7] mm: reduce rmap overhead for ex-KSM page copies created on swap faults

2012-12-19 Thread Johannes Weiner
On Wed, Dec 19, 2012 at 02:01:19AM -0500, Simon Jeons wrote: On Mon, 2012-12-17 at 13:12 -0500, Johannes Weiner wrote: When ex-KSM pages are faulted from swap cache, the fault handler is not capable of re-establishing anon_vma-spanning KSM pages. In this case, a copy of the page is created

Re: [patch 7/7] mm: reduce rmap overhead for ex-KSM page copies created on swap faults

2012-12-18 Thread Simon Jeons
On Mon, 2012-12-17 at 13:12 -0500, Johannes Weiner wrote: > When ex-KSM pages are faulted from swap cache, the fault handler is > not capable of re-establishing anon_vma-spanning KSM pages. In this > case, a copy of the page is created instead, just like during a COW > break. > > These freshly

Re: [patch 7/7] mm: reduce rmap overhead for ex-KSM page copies created on swap faults

2012-12-18 Thread Simon Jeons
On Mon, 2012-12-17 at 13:12 -0500, Johannes Weiner wrote: When ex-KSM pages are faulted from swap cache, the fault handler is not capable of re-establishing anon_vma-spanning KSM pages. In this case, a copy of the page is created instead, just like during a COW break. These freshly made

Re: [patch 7/7] mm: reduce rmap overhead for ex-KSM page copies created on swap faults

2012-12-17 Thread Hugh Dickins
On Mon, 17 Dec 2012, Johannes Weiner wrote: > When ex-KSM pages are faulted from swap cache, the fault handler is > not capable of re-establishing anon_vma-spanning KSM pages. In this > case, a copy of the page is created instead, just like during a COW > break. > > These freshly made copies

[patch 7/7] mm: reduce rmap overhead for ex-KSM page copies created on swap faults

2012-12-17 Thread Johannes Weiner
When ex-KSM pages are faulted from swap cache, the fault handler is not capable of re-establishing anon_vma-spanning KSM pages. In this case, a copy of the page is created instead, just like during a COW break. These freshly made copies are known to be exclusive to the faulting VMA and there is

[patch 7/7] mm: reduce rmap overhead for ex-KSM page copies created on swap faults

2012-12-17 Thread Johannes Weiner
When ex-KSM pages are faulted from swap cache, the fault handler is not capable of re-establishing anon_vma-spanning KSM pages. In this case, a copy of the page is created instead, just like during a COW break. These freshly made copies are known to be exclusive to the faulting VMA and there is

Re: [patch 7/7] mm: reduce rmap overhead for ex-KSM page copies created on swap faults

2012-12-17 Thread Hugh Dickins
On Mon, 17 Dec 2012, Johannes Weiner wrote: When ex-KSM pages are faulted from swap cache, the fault handler is not capable of re-establishing anon_vma-spanning KSM pages. In this case, a copy of the page is created instead, just like during a COW break. These freshly made copies are