On Thu 10 Nov 2022, at 11:36, Gareth Evans <donots...@fastmail.fm> wrote: [...] > I might be barking up the wrong tree ...
But simpler inquiries first. I was wondering if MD might be too high-level to cause what does seem more like a "scheduley" issue - https://www.thomas-krenn.com/de/wikiDE/images/d/d0/Linux-storage-stack-diagram_v4.10.pdf but, apparently, even relatively "normal" processes can cause high iowait too: NFS... https://www.howtouselinux.com/post/troubleshoot-high-iowait-issue-on-linux-system https://www.howtouselinux.com/post/use-linux-nfsiostat-to-troubleshoot-nfs-performance-issue SSH... Use iotop to find io-hogs... https://www.howtouselinux.com/post/quick-guide-to-fix-linux-iowait-issue https://www.howtouselinux.com/post/check-disk-io-usage-per-process-with-iotop-on-linux What's a typical wa value (%) from top? Thanks, G
