On Thu, 2017-08-31 at 15:42 +0100, Mel Gorman wrote:

On Thu, Aug 31, 2017 at 08:46:28AM +0200, Paolo Valente wrote:

quoted

[SECOND TAKE, with just the name of one of the tester fixed]
=20
Hi,
while testing the read-write unfairness issues reported by Mel, I
found BFQ failing to guarantee good responsiveness against heavy
random sync writes in the background, i.e., multiple writers doing
random writes and systematic fdatasync [1]. The failure was caused by
three related bugs, because of which BFQ failed to guarantee to
high-weight processes the expected fraction of the throughput.
=20

=20
Queued on top of Ming's most recent series even though that's still a wor=

k

in progress. I should know in a few days how things stand.

It seems to have cured an interactivity issue I regularly meet during
kbuild final link/depmod phase of fat kernel kbuild, especially bad
with evolution mail usage during that on spinning rust. =C2=A0Can't really
say for sure given this is not based on measurement.

	-Mike=C2=A0