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: > > [SECOND TAKE, with just the name of one of the tester fixed] > > > > 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. > > > > Queued on top of Ming's most recent series even though that's still a work > 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. Can't really say for sure given this is not based on measurement. -Mike
