On 8/8/19 1:03 PM, Johannes Weiner wrote: > psi tracks the time tasks wait for refaulting pages to become > uptodate, but it does not track the time spent submitting the IO. The > submission part can be significant if backing storage is contended or > when cgroup throttling (io.latency) is in effect - a lot of time is > spent in submit_bio(). In that case, we underreport memory pressure. > > Annotate submit_bio() to account submission time as memory stall when > the bio is reading userspace workingset pages. Applied for 5.4. -- Jens Axboe