On 09/06/2018 01:10 PM, Vlastimil Babka wrote:

quoted

We can and should think about this much more but I would like to have
this regression closed. So can we address GFP_THISNODE part first and
build more complex solution on top?

Is there any objection to my patch which does the similar thing to your
patch v2 in a different location?

Similar but not the same. It fixes the madvise case, but I wonder about
the no-madvise defrag=defer case, where Zi Yan reports it still causes
swapping.

Ah, but that should be the same with Andrea's variant 2) patch. There
should only be difference with defrag=always, which is direct reclaim
with __GFP_NORETRY, Andrea's patch would drop __GFP_THISNODE and your
not. Maybe Zi Yan can do the same kind of tests with Andrea's patch [1]
to confirm?

[1] https://marc.info/?l=linux-mm&m=153476267026951