On Mon, Sep 20, 2021 at 09:54:31AM +0100, Mel Gorman wrote: > This has been lightly tested only and the testing was useless as the > relevant code was not executed. The workload configurations I had that > used to trigger these corner cases no longer work (yey?) and I'll need > to implement a new synthetic workload. If someone is aware of a realistic > workload that forces reclaim activity to the point where reclaim stalls > then kindly share the details. The stereeotypical "stalling on I/O" problem is to plug in one of the crap USB drives you were given at a trade show and simply dd if=/dev/zero of=/dev/sdb sync You can also set up qemu to have extremely slow I/O performance: https://serverfault.com/questions/675704/extremely-slow-qemu-storage-performance-with-qcow2-images
