Hi guys. Earlier this year I installed fio (from latest source) on a CentOS 7.4 install, and had nothing but stellar operation - very smooth, very good. Recently I've done the same on a CentOS 7.5 install, and I'm having difficulties. I've rolled back my target software to known good (we're storage developers), I've tested with both os drivers and spdk, and I've tried to roll back the fio snapshot as well, all to no avail. The symptom varies depending on whether or not I'm using spdk - without spdk, I see my performance drop but not to zero, after the test has run successfully for some random but usually small length of time. With spdk, I/O seems to stop completely after a similar length of time. With spdk the fio output line ceases to show ay bandwidth or IOPS info. The timer will count down to zero, but the job doesn't stop; the timer just resets itself to some large value and things continue to run. With spdk, before the problem I can use ctrl-C to interrupt the job; afterthe problem I can't - I have to use kill -9. Tests with spdk's "perf" utility have uniformly seemed to run perfectly - that's the primary reason I don't believe spdk is the issue here (well, that and the fact that I also have problems with the os drivers). The behavior in fio isn't exactly the same with and without os drivers, but it's problematic in both cases. I THINK I have probed old fio build points enough to think that this isn't arising from a recent change in fio. My main suspicion right now is that something is different in CentOS 7.5 that fio is unhappy with - is anyone aware of issues with that particular Linux distro? Thanks very much, Kip
