Messages in this thread | | | Date | Thu, 01 Mar 2012 12:06:46 +0400 | From | Konstantin Khlebnikov <> | Subject | Re: [PATCH resend] mm: drain percpu lru add/rotate page-vectors on cpu hot-unplug |
| |
Andrew Morton wrote: > On Tue, 28 Feb 2012 23:40:45 +0400 > Konstantin Khlebnikov<khlebnikov@openvz.org> wrote: > >> This cpu hotplug hook was accidentally removed in commit v2.6.30-rc4-18-g00a62ce >> ("mm: fix Committed_AS underflow on large NR_CPUS environment") > > That was a long time ago - maybe we should leave it removed ;) I mean, > did this bug(?) have any visible effect? If so, what was that effect?
It's because cpu hotplug/unplug isn't widely used feature. Visible effect -- some pages are borrowed in per-cpu page-vectors. Truncate can deal with it, but these pages cannot be reused while this cpu is offline. So this is like temporary memory leak.
> > IOW, the changelog didn't give anyone any reason to apply the patch to > anything!
Sorry, I'm just stuck in pile of patches. It seems I should stop and send them one by one. This one isn't critical, so there no reasons for pushing it into stable branches.
| |