On Wed, 06 Oct 2021, Charles Hedrick wrote: > > It tried running vmplayer. Shortly after starting to create a new VM, > vmplayer hung. I had another window with a shell. I went into the > directory with the vm files and did “ls -ltrc”. It didn’t quite hang, > but look about a minute to finish I also saw log entries from VMware > complaining that disk operations took several seconds. Useful information to provide when a process appears to hang on NFS include: - cat /proc/$PID/stack - rpcdebug -m nfs -s all; rpcdebug -m rpc -s all ; sleep 2 ; rpcdebug -m rpc -c all; rpcdebug -m nfs -c all then collect kernel logs - tcpdump -w filename.pcap -s 0 -c 1000 port 2049 and compress filename.pcap and put it somewhere we can find it. - trace-cmd record -e 'nfs:*' sleep 2 trace-cmd report > filename > > We’re probably an unusual installation. We’re a CS department, with > researchers and also a large time-sharing environment for students > (spread across many machines, with a graphical interface using Xrdb, > etc). Our people use every piece of software under the sun. Probably not all that unusual. There certainly are lots of large and varied NFS sites out there. > > Client and server are both Ubuntu 20.04. Server is on ZFS with NVMe storage. If it is possible to reproduce without ZFS, that would provide useful information. I don't think it is *likely* that ZFS causes the problem, but neither would I be surprised if it did. NeilBrown
