On Mon, Nov 29, 2021 at 11:13:34PM -0800, dai.ngo@xxxxxxxxxx wrote: > Just to be clear, the problem of pynfs with 4.0 is that the server takes > ~55 secs to expire 1026 4.0 courteous clients, which comes out to ~50ms > per client. This causes the test to time out in waiting for RPC reply of > the OPEN that triggers the conflicts. > > I don't know exactly where the time spent in the process of expiring a > client. But as Bruce mentioned, it could be related to the time to access > /var/lib/nfs to remove the client's persistent record. Could you try something like strace -r -$(pidof) -oTRACE and maybe we could take a look at TRACE? My hope would be that there'd be a clear set of syscalls whose time, multiplied by 1026, explains most of that 55 seconds. Then it might be worth checking whether there are any easy optimizations possible. --b.