Re: Is it safe for kthreadd to drain_all_pages?

2017-04-13 Thread Andrea Arcangeli
Hello, On Sat, Apr 08, 2017 at 07:09:10PM +0100, Mel Gorman wrote: > On Sat, Apr 08, 2017 at 10:04:20AM -0700, Hugh Dickins wrote: > > On Fri, 7 Apr 2017, Hugh Dickins wrote: > > > On Fri, 7 Apr 2017, Michal Hocko wrote: > > > > On Fri 07-04-17 09:58:17, Hugh Dickins wrote: > > > > > On Fri, 7

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-13 Thread Andrea Arcangeli
Hello, On Sat, Apr 08, 2017 at 07:09:10PM +0100, Mel Gorman wrote: > On Sat, Apr 08, 2017 at 10:04:20AM -0700, Hugh Dickins wrote: > > On Fri, 7 Apr 2017, Hugh Dickins wrote: > > > On Fri, 7 Apr 2017, Michal Hocko wrote: > > > > On Fri 07-04-17 09:58:17, Hugh Dickins wrote: > > > > > On Fri, 7

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-08 Thread Mel Gorman
On Sat, Apr 08, 2017 at 10:04:20AM -0700, Hugh Dickins wrote: > On Fri, 7 Apr 2017, Hugh Dickins wrote: > > On Fri, 7 Apr 2017, Michal Hocko wrote: > > > On Fri 07-04-17 09:58:17, Hugh Dickins wrote: > > > > On Fri, 7 Apr 2017, Michal Hocko wrote: > > > > > On Fri 07-04-17 09:25:33, Hugh Dickins

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-08 Thread Mel Gorman
On Sat, Apr 08, 2017 at 10:04:20AM -0700, Hugh Dickins wrote: > On Fri, 7 Apr 2017, Hugh Dickins wrote: > > On Fri, 7 Apr 2017, Michal Hocko wrote: > > > On Fri 07-04-17 09:58:17, Hugh Dickins wrote: > > > > On Fri, 7 Apr 2017, Michal Hocko wrote: > > > > > On Fri 07-04-17 09:25:33, Hugh Dickins

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-08 Thread Hugh Dickins
On Fri, 7 Apr 2017, Hugh Dickins wrote: > On Fri, 7 Apr 2017, Michal Hocko wrote: > > On Fri 07-04-17 09:58:17, Hugh Dickins wrote: > > > On Fri, 7 Apr 2017, Michal Hocko wrote: > > > > On Fri 07-04-17 09:25:33, Hugh Dickins wrote: > > > > [...] > > > > > 24 hours so far, and with a clean

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-08 Thread Hugh Dickins
On Fri, 7 Apr 2017, Hugh Dickins wrote: > On Fri, 7 Apr 2017, Michal Hocko wrote: > > On Fri 07-04-17 09:58:17, Hugh Dickins wrote: > > > On Fri, 7 Apr 2017, Michal Hocko wrote: > > > > On Fri 07-04-17 09:25:33, Hugh Dickins wrote: > > > > [...] > > > > > 24 hours so far, and with a clean

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-07 Thread Hugh Dickins
On Fri, 7 Apr 2017, Michal Hocko wrote: > On Fri 07-04-17 09:58:17, Hugh Dickins wrote: > > On Fri, 7 Apr 2017, Michal Hocko wrote: > > > On Fri 07-04-17 09:25:33, Hugh Dickins wrote: > > > [...] > > > > 24 hours so far, and with a clean /var/log/messages. Not conclusive > > > > yet, and of

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-07 Thread Hugh Dickins
On Fri, 7 Apr 2017, Michal Hocko wrote: > On Fri 07-04-17 09:58:17, Hugh Dickins wrote: > > On Fri, 7 Apr 2017, Michal Hocko wrote: > > > On Fri 07-04-17 09:25:33, Hugh Dickins wrote: > > > [...] > > > > 24 hours so far, and with a clean /var/log/messages. Not conclusive > > > > yet, and of

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-07 Thread Michal Hocko
On Fri 07-04-17 09:58:17, Hugh Dickins wrote: > On Fri, 7 Apr 2017, Michal Hocko wrote: > > On Fri 07-04-17 09:25:33, Hugh Dickins wrote: > > [...] > > > 24 hours so far, and with a clean /var/log/messages. Not conclusive > > > yet, and of course I'll leave it running another couple of days, but

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-07 Thread Michal Hocko
On Fri 07-04-17 09:58:17, Hugh Dickins wrote: > On Fri, 7 Apr 2017, Michal Hocko wrote: > > On Fri 07-04-17 09:25:33, Hugh Dickins wrote: > > [...] > > > 24 hours so far, and with a clean /var/log/messages. Not conclusive > > > yet, and of course I'll leave it running another couple of days, but

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-07 Thread Hugh Dickins
On Fri, 7 Apr 2017, Michal Hocko wrote: > On Fri 07-04-17 09:25:33, Hugh Dickins wrote: > [...] > > 24 hours so far, and with a clean /var/log/messages. Not conclusive > > yet, and of course I'll leave it running another couple of days, but > > I'm increasingly sure that it works as you intended:

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-07 Thread Hugh Dickins
On Fri, 7 Apr 2017, Michal Hocko wrote: > On Fri 07-04-17 09:25:33, Hugh Dickins wrote: > [...] > > 24 hours so far, and with a clean /var/log/messages. Not conclusive > > yet, and of course I'll leave it running another couple of days, but > > I'm increasingly sure that it works as you intended:

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-07 Thread Michal Hocko
On Fri 07-04-17 09:25:33, Hugh Dickins wrote: [...] > 24 hours so far, and with a clean /var/log/messages. Not conclusive > yet, and of course I'll leave it running another couple of days, but > I'm increasingly sure that it works as you intended: I agree that > >

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-07 Thread Michal Hocko
On Fri 07-04-17 09:25:33, Hugh Dickins wrote: [...] > 24 hours so far, and with a clean /var/log/messages. Not conclusive > yet, and of course I'll leave it running another couple of days, but > I'm increasingly sure that it works as you intended: I agree that > >

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-07 Thread Hugh Dickins
On Thu, 6 Apr 2017, Hugh Dickins wrote: > On Thu, 6 Apr 2017, Mel Gorman wrote: > > On Wed, Apr 05, 2017 at 01:59:49PM -0700, Hugh Dickins wrote: > > > Hi Mel, > > > > > > I suspect that it's not safe for kthreadd to drain_all_pages(); > > > but I have

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-07 Thread Hugh Dickins
On Thu, 6 Apr 2017, Hugh Dickins wrote: > On Thu, 6 Apr 2017, Mel Gorman wrote: > > On Wed, Apr 05, 2017 at 01:59:49PM -0700, Hugh Dickins wrote: > > > Hi Mel, > > > > > > I suspect that it's not safe for kthreadd to drain_all_pages(); > > > but I have

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-06 Thread Hugh Dickins
On Thu, 6 Apr 2017, Mel Gorman wrote: > On Wed, Apr 05, 2017 at 01:59:49PM -0700, Hugh Dickins wrote: > > Hi Mel, > > > > I suspect that it's not safe for kthreadd to drain_all_pages(); > > but I haven't studied flush_work() etc, so don't really know what > > I

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-06 Thread Hugh Dickins
On Thu, 6 Apr 2017, Mel Gorman wrote: > On Wed, Apr 05, 2017 at 01:59:49PM -0700, Hugh Dickins wrote: > > Hi Mel, > > > > I suspect that it's not safe for kthreadd to drain_all_pages(); > > but I haven't studied flush_work() etc, so don't really know what > > I

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-06 Thread Mel Gorman
On Wed, Apr 05, 2017 at 01:59:49PM -0700, Hugh Dickins wrote: > Hi Mel, > > I suspect that it's not safe for kthreadd to drain_all_pages(); > but I haven't studied flush_work() etc, so don't really know what > I'm talking about: hoping that you will jump to a realization. >

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-06 Thread Mel Gorman
On Wed, Apr 05, 2017 at 01:59:49PM -0700, Hugh Dickins wrote: > Hi Mel, > > I suspect that it's not safe for kthreadd to drain_all_pages(); > but I haven't studied flush_work() etc, so don't really know what > I'm talking about: hoping that you will jump to a realization. >

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-06 Thread Michal Hocko
On Wed 05-04-17 13:59:49, Hugh Dickins wrote: > Hi Mel, > > I suspect that it's not safe for kthreadd to drain_all_pages(); > but I haven't studied flush_work() etc, so don't really know what > I'm talking about: hoping that you will jump to a realization. > > 4.11-rc has

Re: Is it safe for kthreadd to drain_all_pages?

2017-04-06 Thread Michal Hocko
On Wed 05-04-17 13:59:49, Hugh Dickins wrote: > Hi Mel, > > I suspect that it's not safe for kthreadd to drain_all_pages(); > but I haven't studied flush_work() etc, so don't really know what > I'm talking about: hoping that you will jump to a realization. > > 4.11-rc has

Is it safe for kthreadd to drain_all_pages?

2017-04-05 Thread Hugh Dickins
Hi Mel, I suspect that it's not safe for kthreadd to drain_all_pages(); but I haven't studied flush_work() etc, so don't really know what I'm talking about: hoping that you will jump to a realization. 4.11-rc has been giving me hangs after hours of swapping load. At first they looked like

Is it safe for kthreadd to drain_all_pages?

2017-04-05 Thread Hugh Dickins
Hi Mel, I suspect that it's not safe for kthreadd to drain_all_pages(); but I haven't studied flush_work() etc, so don't really know what I'm talking about: hoping that you will jump to a realization. 4.11-rc has been giving me hangs after hours of swapping load. At first they looked like