[ Resending this mail with a dropbox link to the traces (instead of a file attachment), since it didn't go through the last time. ] On 5/21/19 10:38 AM, Paolo Valente wrote: > >> So, instead of only sending me a trace, could you please: >> 1) apply this new patch on top of the one I attached in my previous email >> 2) repeat your test and report results > > One last thing (I swear!): as you can see from my script, I tested the > case low_latency=0 so far. So please, for the moment, do your test > with low_latency=0. You find the whole path to this parameter in, > e.g., my script. > No problem! :) Thank you for sharing patches for me to test! I have good news :) Your patch improves the throughput significantly when low_latency = 0. Without any patch: dd if=/dev/zero of=/root/test.img bs=512 count=10000 oflag=dsync 10000+0 records in 10000+0 records out 5120000 bytes (5.1 MB, 4.9 MiB) copied, 58.0915 s, 88.1 kB/s With both patches applied: dd if=/dev/zero of=/root/test0.img bs=512 count=10000 oflag=dsync 10000+0 records in 10000+0 records out 5120000 bytes (5.1 MB, 4.9 MiB) copied, 3.87487 s, 1.3 MB/s The performance is still not as good as mq-deadline (which achieves 1.6 MB/s), but this is a huge improvement for BFQ nonetheless! A tarball with the trace output from the 2 scenarios you requested, one with only the debug patch applied (trace-bfq-add-logs-and-BUG_ONs), and another with both patches applied (trace-bfq-boost-injection) is available here: https://www.dropbox.com/s/pdf07vi7afido7e/bfq-traces.tar.gz?dl=0 Thank you! Regards, Srivatsa VMware Photon OS
