Re: [PATCH 11/24] huge tmpfs: shrinker to migrate and free underused holes

2015-03-24 Thread Hugh Dickins
On Tue, 24 Mar 2015, Kirill A. Shutemov wrote: > On Sun, Mar 22, 2015 at 09:40:02PM -0700, Hugh Dickins wrote: > > (I think Kirill has a problem of that kind in his page_remove_rmap scan). (And this one I mentioned to you at the conference :) > > > > It will be interesting to see what Kirill doe

Re: [PATCH 11/24] huge tmpfs: shrinker to migrate and free underused holes

2015-03-24 Thread Kirill A. Shutemov
On Sun, Mar 22, 2015 at 09:40:02PM -0700, Hugh Dickins wrote: > (I think Kirill has a problem of that kind in his page_remove_rmap scan). > > It will be interesting to see what Kirill does to maintain the stats > for huge pagecache: but he will have no difficulty in finding fields > to store count

Re: [PATCH 11/24] huge tmpfs: shrinker to migrate and free underused holes

2015-03-23 Thread Kirill A. Shutemov
On Mon, Mar 23, 2015 at 02:50:09PM +0200, Kirill A. Shutemov wrote: > On Sun, Mar 22, 2015 at 09:40:02PM -0700, Hugh Dickins wrote: > > (I think Kirill has a problem of that kind in his page_remove_rmap scan). > > Ouch! Thanks for noticing this. > > It should work fine while we are anon-THP only

Re: [PATCH 11/24] huge tmpfs: shrinker to migrate and free underused holes

2015-03-23 Thread Kirill A. Shutemov
On Sun, Mar 22, 2015 at 09:40:02PM -0700, Hugh Dickins wrote: > (I think Kirill has a problem of that kind in his page_remove_rmap scan). Ouch! Thanks for noticing this. It should work fine while we are anon-THP only, but it need to be fixed to work with files. -- Kirill A. Shutemov -- To uns

Re: [PATCH 11/24] huge tmpfs: shrinker to migrate and free underused holes

2015-03-22 Thread Hugh Dickins
On Thu, 19 Mar 2015, Konstantin Khlebnikov wrote: > On 21.02.2015 07:09, Hugh Dickins wrote: > > > > The "team_usage" field added to struct page (in union with "private") > > is somewhat vaguely named: because while the huge page is sparsely > > occupied, it counts the occupancy; but once the huge

Re: [PATCH 11/24] huge tmpfs: shrinker to migrate and free underused holes

2015-03-19 Thread Konstantin Khlebnikov
On 21.02.2015 07:09, Hugh Dickins wrote: Using 2MB for each small file is wasteful, and on average even a large file is likely to waste 1MB at the end. We could say that a huge tmpfs is only suitable for huge files, but I would much prefer not to limit it in that way, and would not be very able

[PATCH 11/24] huge tmpfs: shrinker to migrate and free underused holes

2015-02-20 Thread Hugh Dickins
Using 2MB for each small file is wasteful, and on average even a large file is likely to waste 1MB at the end. We could say that a huge tmpfs is only suitable for huge files, but I would much prefer not to limit it in that way, and would not be very able to test such a filesystem. In our model, t