Re: [PATCH v2 00/10] try to reduce fragmenting fallbacks

Mel Gorman
2017-02-23T16:01:28Z

On Mon, Feb 20, 2017 at 01:30:33PM +0100, Vlastimil Babka wrote:
> On 02/13/2017 12:07 PM, Mel Gorman wrote:
> > On Fri, Feb 10, 2017 at 06:23:33PM +0100, Vlastimil Babka wrote:
> >
> > By and large, I like the series, particularly patches 7 and 8. I cannot
> > make up my mind about the RFC patches 9 and 10 yet. Conceptually they
> > seem sound but they are much more far reaching than the rest of the
> > series.
> >
> > It would be nice if patches 1-8 could be treated in isolation with data
> > on the number of extfrag events triggered, time spent in compaction and
> > the success rate. Patches 9 and 10 are tricy enough that they would need
> > data per patch where as patches 1-8 should be ok with data gathered for
> > the whole series.
>
> Ok let's try again with a fresh subthread after fixing automation and
> postprocessing...
>
> <SNIP>
>
> To sum up, patches 1-8 look OK to me. Patch 9 looks also very promising, but
> there's danger of increased allocation latencies due to the forced compaction.
> Patch 10 has either implementation bugs or there's some unforeseen consequence
> of its design.
>

I don't have anything useful to add other than the figures for patches
1-8 look good and the fact that fragmenting events that misplace unmovable
allocations is welcome.

--
Mel Gorman
SUSE Labs