Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-10 Thread Joonsoo Kim
On Wed, Feb 04, 2015 at 03:39:25PM +0100, Vlastimil Babka wrote: > On 02/03/2015 06:07 PM, Joonsoo Kim wrote: > >2015-02-04 0:51 GMT+09:00 Vlastimil Babka : > >>Ah, I think I see where the misunderstanding comes from now. So to clarify, > >>let's consider > >> > >>1. single compaction run - single

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-10 Thread Joonsoo Kim
On Wed, Feb 04, 2015 at 03:39:25PM +0100, Vlastimil Babka wrote: On 02/03/2015 06:07 PM, Joonsoo Kim wrote: 2015-02-04 0:51 GMT+09:00 Vlastimil Babka vba...@suse.cz: Ah, I think I see where the misunderstanding comes from now. So to clarify, let's consider 1. single compaction run - single

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-04 Thread Vlastimil Babka
On 02/03/2015 06:07 PM, Joonsoo Kim wrote: 2015-02-04 0:51 GMT+09:00 Vlastimil Babka : Ah, I think I see where the misunderstanding comes from now. So to clarify, let's consider 1. single compaction run - single invocation of compact_zone(). It can start from cached pfn's from previous run, or

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-04 Thread Vlastimil Babka
On 02/03/2015 06:07 PM, Joonsoo Kim wrote: 2015-02-04 0:51 GMT+09:00 Vlastimil Babka vba...@suse.cz: Ah, I think I see where the misunderstanding comes from now. So to clarify, let's consider 1. single compaction run - single invocation of compact_zone(). It can start from cached pfn's from

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-03 Thread Joonsoo Kim
2015-02-04 0:51 GMT+09:00 Vlastimil Babka : > On 02/03/2015 04:00 PM, Joonsoo Kim wrote: >> 2015-02-03 18:05 GMT+09:00 Vlastimil Babka : >>> On 02/03/2015 07:49 AM, Joonsoo Kim wrote: On Mon, Jan 19, 2015 at 11:05:15AM +0100, Vlastimil Babka wrote: Hello, I don't have any

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-03 Thread Vlastimil Babka
On 02/03/2015 04:00 PM, Joonsoo Kim wrote: > 2015-02-03 18:05 GMT+09:00 Vlastimil Babka : >> On 02/03/2015 07:49 AM, Joonsoo Kim wrote: >>> On Mon, Jan 19, 2015 at 11:05:15AM +0100, Vlastimil Babka wrote: >>> >>> Hello, >>> >>> I don't have any elegant idea, but, have some humble opinion. >>> >>>

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-03 Thread Joonsoo Kim
2015-02-03 18:05 GMT+09:00 Vlastimil Babka : > On 02/03/2015 07:49 AM, Joonsoo Kim wrote: >> On Mon, Jan 19, 2015 at 11:05:15AM +0100, Vlastimil Babka wrote: >> >> Hello, >> >> I don't have any elegant idea, but, have some humble opinion. >> >> The point is that migrate scanner should scan whole

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-03 Thread Vlastimil Babka
On 02/03/2015 07:49 AM, Joonsoo Kim wrote: > On Mon, Jan 19, 2015 at 11:05:15AM +0100, Vlastimil Babka wrote: > > Hello, > > I don't have any elegant idea, but, have some humble opinion. > > The point is that migrate scanner should scan whole zone. > Although your pivot approach makes some

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-03 Thread Joonsoo Kim
2015-02-03 18:05 GMT+09:00 Vlastimil Babka vba...@suse.cz: On 02/03/2015 07:49 AM, Joonsoo Kim wrote: On Mon, Jan 19, 2015 at 11:05:15AM +0100, Vlastimil Babka wrote: Hello, I don't have any elegant idea, but, have some humble opinion. The point is that migrate scanner should scan whole

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-03 Thread Vlastimil Babka
On 02/03/2015 07:49 AM, Joonsoo Kim wrote: On Mon, Jan 19, 2015 at 11:05:15AM +0100, Vlastimil Babka wrote: Hello, I don't have any elegant idea, but, have some humble opinion. The point is that migrate scanner should scan whole zone. Although your pivot approach makes some sense and it

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-03 Thread Vlastimil Babka
On 02/03/2015 04:00 PM, Joonsoo Kim wrote: 2015-02-03 18:05 GMT+09:00 Vlastimil Babka vba...@suse.cz: On 02/03/2015 07:49 AM, Joonsoo Kim wrote: On Mon, Jan 19, 2015 at 11:05:15AM +0100, Vlastimil Babka wrote: Hello, I don't have any elegant idea, but, have some humble opinion. The point

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-03 Thread Joonsoo Kim
2015-02-04 0:51 GMT+09:00 Vlastimil Babka vba...@suse.cz: On 02/03/2015 04:00 PM, Joonsoo Kim wrote: 2015-02-03 18:05 GMT+09:00 Vlastimil Babka vba...@suse.cz: On 02/03/2015 07:49 AM, Joonsoo Kim wrote: On Mon, Jan 19, 2015 at 11:05:15AM +0100, Vlastimil Babka wrote: Hello, I don't have

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-02 Thread Joonsoo Kim
On Mon, Jan 19, 2015 at 11:05:15AM +0100, Vlastimil Babka wrote: > Even after all the patches compaction received in last several versions, it > turns out that its effectivneess degrades considerably as the system ages > after reboot. For example, see how success rates of stress-highalloc from >

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-02-02 Thread Joonsoo Kim
On Mon, Jan 19, 2015 at 11:05:15AM +0100, Vlastimil Babka wrote: Even after all the patches compaction received in last several versions, it turns out that its effectivneess degrades considerably as the system ages after reboot. For example, see how success rates of stress-highalloc from

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-01-20 Thread Vlastimil Babka
On 01/19/2015 11:05 AM, Vlastimil Babka wrote: > Preliminary testing with THP-like allocations has shown similar improvements, > which is somewhat surprising, because THP allocations do not use sync > and thus do not defer compaction; but changing the pivot is currently tied > to restarting from

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-01-20 Thread Vlastimil Babka
On 01/19/2015 11:05 AM, Vlastimil Babka wrote: Preliminary testing with THP-like allocations has shown similar improvements, which is somewhat surprising, because THP allocations do not use sync and thus do not defer compaction; but changing the pivot is currently tied to restarting from

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-01-19 Thread Vlastimil Babka
Looks like wrapping got busted in the results part. Let's try again: - Even after all the patches compaction received in last several versions, it turns out that its effectivneess degrades considerably as the system ages after reboot. For example, see how success rates of stress-highalloc

[RFC PATCH 0/5] compaction: changing initial position of scanners

2015-01-19 Thread Vlastimil Babka
Even after all the patches compaction received in last several versions, it turns out that its effectivneess degrades considerably as the system ages after reboot. For example, see how success rates of stress-highalloc from mmtests degrades when we re-execute it several times, first time being

Re: [RFC PATCH 0/5] compaction: changing initial position of scanners

2015-01-19 Thread Vlastimil Babka
Looks like wrapping got busted in the results part. Let's try again: - Even after all the patches compaction received in last several versions, it turns out that its effectivneess degrades considerably as the system ages after reboot. For example, see how success rates of stress-highalloc

[RFC PATCH 0/5] compaction: changing initial position of scanners

2015-01-19 Thread Vlastimil Babka
Even after all the patches compaction received in last several versions, it turns out that its effectivneess degrades considerably as the system ages after reboot. For example, see how success rates of stress-highalloc from mmtests degrades when we re-execute it several times, first time being