Re: [PATCH] vmscan: do not throttle kthreads due to too_many_isolated

2015-12-02 Thread Michal Hocko
On Tue 01-12-15 14:25:45, Vladimir Davydov wrote: > On Fri, Nov 27, 2015 at 04:01:33PM +0100, Michal Hocko wrote: > > On Fri 27-11-15 16:40:03, Vladimir Davydov wrote: [...] > > > The problem is not about our driver, in fact. I'm pretty sure one can > > > hit it when using memcg along with loop or

Re: [PATCH] vmscan: do not throttle kthreads due to too_many_isolated

2015-12-01 Thread Vladimir Davydov
On Fri, Nov 27, 2015 at 04:01:33PM +0100, Michal Hocko wrote: > On Fri 27-11-15 16:40:03, Vladimir Davydov wrote: > > On Fri, Nov 27, 2015 at 01:50:05PM +0100, Michal Hocko wrote: > > > On Thu 26-11-15 11:16:24, Vladimir Davydov wrote: > [...] > > > > Anyway, kthreads that use GFP_NOIO and/or mempo

Re: [PATCH] vmscan: do not throttle kthreads due to too_many_isolated

2015-11-27 Thread Michal Hocko
On Fri 27-11-15 16:40:03, Vladimir Davydov wrote: > On Fri, Nov 27, 2015 at 01:50:05PM +0100, Michal Hocko wrote: > > On Thu 26-11-15 11:16:24, Vladimir Davydov wrote: [...] > > > Anyway, kthreads that use GFP_NOIO and/or mempool aren't safe either, > > > because it isn't an allocation context prob

Re: [PATCH] vmscan: do not throttle kthreads due to too_many_isolated

2015-11-27 Thread Vladimir Davydov
On Fri, Nov 27, 2015 at 01:50:05PM +0100, Michal Hocko wrote: > On Thu 26-11-15 11:16:24, Vladimir Davydov wrote: > > On Wed, Nov 25, 2015 at 07:27:57PM +0300, Vladimir Davydov wrote: > > > On Wed, Nov 25, 2015 at 04:45:13PM +0100, Vlastimil Babka wrote: > > > > On 11/25/2015 04:36 PM, Vladimir Dav

Re: [PATCH] vmscan: do not throttle kthreads due to too_many_isolated

2015-11-27 Thread Michal Hocko
On Thu 26-11-15 11:16:24, Vladimir Davydov wrote: > On Wed, Nov 25, 2015 at 07:27:57PM +0300, Vladimir Davydov wrote: > > On Wed, Nov 25, 2015 at 04:45:13PM +0100, Vlastimil Babka wrote: > > > On 11/25/2015 04:36 PM, Vladimir Davydov wrote: > > > > Block device drivers often hand off io request pro

Re: [PATCH] vmscan: do not throttle kthreads due to too_many_isolated

2015-11-26 Thread Vladimir Davydov
On Wed, Nov 25, 2015 at 07:27:57PM +0300, Vladimir Davydov wrote: > On Wed, Nov 25, 2015 at 04:45:13PM +0100, Vlastimil Babka wrote: > > On 11/25/2015 04:36 PM, Vladimir Davydov wrote: > > > Block device drivers often hand off io request processing to kernel > > > threads (example: device mapper).

Re: [PATCH] vmscan: do not throttle kthreads due to too_many_isolated

2015-11-25 Thread Vladimir Davydov
On Wed, Nov 25, 2015 at 04:45:13PM +0100, Vlastimil Babka wrote: > On 11/25/2015 04:36 PM, Vladimir Davydov wrote: > > Block device drivers often hand off io request processing to kernel > > threads (example: device mapper). If such a thread calls kmalloc, it can > > dive into direct reclaim path a

Re: [PATCH] vmscan: do not throttle kthreads due to too_many_isolated

2015-11-25 Thread Vlastimil Babka
On 11/25/2015 04:36 PM, Vladimir Davydov wrote: > Block device drivers often hand off io request processing to kernel > threads (example: device mapper). If such a thread calls kmalloc, it can > dive into direct reclaim path and end up waiting for too_many_isolated > to return false, blocking write