Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-02-14 Thread Hugh Dickins
On Thu, 14 Feb 2013, Mel Gorman wrote: > On Fri, Feb 08, 2013 at 11:33:40AM -0800, Hugh Dickins wrote: > > > > What I found is that a 4th cause emerges once KSM migration > > is properly working: that interval during page migration when the old > > page has been fully unmapped but the new not yet

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-02-14 Thread Mel Gorman
On Fri, Feb 08, 2013 at 11:33:40AM -0800, Hugh Dickins wrote: > > > > > > > > > 2. __ksm_enter() has a nice little optimization, to insert the new mm > > > just behind ksmd's cursor, so there's a full pass for it to stabilize > > > (or be removed) before ksmd addresses it. Nice when ksmd is runn

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-02-08 Thread Hugh Dickins
On Tue, 5 Feb 2013, Mel Gorman wrote: > On Fri, Jan 25, 2013 at 06:01:59PM -0800, Hugh Dickins wrote: > > Switching merge_across_nodes after running KSM is liable to oops on stale > > nodes still left over from the previous stable tree. It's not something > > that people will often want to do, but

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-02-05 Thread Mel Gorman
On Fri, Jan 25, 2013 at 06:01:59PM -0800, Hugh Dickins wrote: > Switching merge_across_nodes after running KSM is liable to oops on stale > nodes still left over from the previous stable tree. It's not something > that people will often want to do, but it would be lame to demand a reboot > when th

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-01-28 Thread Hugh Dickins
On Mon, 28 Jan 2013, Andrew Morton wrote: > On Fri, 25 Jan 2013 18:01:59 -0800 (PST) > Hugh Dickins wrote: > > > +static int remove_all_stable_nodes(void) > > +{ > > + struct stable_node *stable_node; > > + int nid; > > + int err = 0; > > + > > + for (nid = 0; nid < nr_node_ids; nid++) {

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-01-28 Thread Andrew Morton
On Fri, 25 Jan 2013 18:01:59 -0800 (PST) Hugh Dickins wrote: > +static int remove_all_stable_nodes(void) > +{ > + struct stable_node *stable_node; > + int nid; > + int err = 0; > + > + for (nid = 0; nid < nr_node_ids; nid++) { > + while (root_stable_tree[nid].rb_node)

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-01-27 Thread Simon Jeons
On Fri, 2013-01-25 at 18:01 -0800, Hugh Dickins wrote: > Switching merge_across_nodes after running KSM is liable to oops on stale > nodes still left over from the previous stable tree. It's not something > that people will often want to do, but it would be lame to demand a reboot > when they're t

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-01-27 Thread Hugh Dickins
On Sun, 27 Jan 2013, Simon Jeons wrote: > On Fri, 2013-01-25 at 18:01 -0800, Hugh Dickins wrote: > > Switching merge_across_nodes after running KSM is liable to oops on stale > > nodes still left over from the previous stable tree. It's not something > > Since this patch solve the problem, so the

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-01-27 Thread Hugh Dickins
On Sun, 27 Jan 2013, Simon Jeons wrote: > On Sun, 2013-01-27 at 15:05 -0800, Hugh Dickins wrote: > > On Sat, 26 Jan 2013, Simon Jeons wrote: > > > > How can this happen? We only permit switching merge_across_nodes when > > > > pages_shared is 0, and usually set run 2 to force that beforehand, whic

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-01-27 Thread Simon Jeons
On Fri, 2013-01-25 at 18:01 -0800, Hugh Dickins wrote: > Switching merge_across_nodes after running KSM is liable to oops on stale > nodes still left over from the previous stable tree. It's not something Since this patch solve the problem, so the description of merge_across_nodes(Value can be ch

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-01-27 Thread Simon Jeons
On Sun, 2013-01-27 at 15:05 -0800, Hugh Dickins wrote: > On Sat, 26 Jan 2013, Simon Jeons wrote: > > On Fri, 2013-01-25 at 18:01 -0800, Hugh Dickins wrote: > > > Switching merge_across_nodes after running KSM is liable to oops on stale > > > nodes still left over from the previous stable tree. It'

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-01-27 Thread Hugh Dickins
On Sat, 26 Jan 2013, Simon Jeons wrote: > On Fri, 2013-01-25 at 18:01 -0800, Hugh Dickins wrote: > > Switching merge_across_nodes after running KSM is liable to oops on stale > > nodes still left over from the previous stable tree. It's not something > > that people will often want to do, but it w

Re: [PATCH 6/11] ksm: remove old stable nodes more thoroughly

2013-01-26 Thread Simon Jeons
Hi Hugh, On Fri, 2013-01-25 at 18:01 -0800, Hugh Dickins wrote: > Switching merge_across_nodes after running KSM is liable to oops on stale > nodes still left over from the previous stable tree. It's not something > that people will often want to do, but it would be lame to demand a reboot > when