Re: [PATCH v3 0/3] Enable >0 order folio memory compaction

From: Baolin Wang
Date: Mon Feb 05 2024 - 03:16:50 EST




On 2/3/2024 12:15 AM, Zi Yan wrote:
From: Zi Yan <ziy@xxxxxxxxxx>

Hi all,

This patchset enables >0 order folio memory compaction, which is one of
the prerequisitions for large folio support[1]. It includes the fix[4] for
V2 and is on top of mm-everything-2024-01-29-07-19.

I am aware of that split free pages is necessary for folio
migration in compaction, since if >0 order free pages are never split
and no order-0 free page is scanned, compaction will end prematurely due
to migration returns -ENOMEM. Free page split becomes a must instead of
an optimization.

lkp ncompare results for default LRU (-no-mglru) and CONFIG_LRU_GEN are
shown at the bottom (on a 8-CPU (Intel Xeon E5-2650 v4 @ 2.20GHz) 16G VM).
In sum, most of vm-scalability applications do not see performance change,
and the others see ~4% to ~26% performance boost under default LRU and
~2% to ~6% performance boost under CONFIG_LRU_GEN.

For the whole series, looks good to me. And I did not find any regression after running thpcompact. So feel free to add:
Reviewed-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Tested-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>