On Tue 31 Jul 2018 06:47:53 PM CEST, Alberto Garcia wrote: > On Wed 04 Jul 2018 04:54:10 PM CEST, Stefan Hajnoczi wrote: >> Throttle groups consist of members sharing one throttling state >> (including bps/iops limits). Round-robin scheduling is used to ensure >> fairness. If a group member already has a timer pending then other >> groups members do not schedule their own timers. The next group >> member will have its turn when the existing timer expires. >> >> A hang may occur when a group member leaves while it had a timer >> scheduled. > > Ok, I can reproduce this if I run fio with iodepth=1.
I managed to write a test case for this, but unfortunately it seems that this patch is not enough and it's still possible to hang QEMU 3.0.0-rc2. I expect to have a fix for tomorrow. Berto
