On Sun, Feb 26, 2023 at 11:02:53PM +0700, Ammar Faizi wrote: > Hi, > > This is an RFC patchset that introduces the `wq_cpu_set` mount option. > This option lets the user specify a CPU set that the Btrfs workqueues > will use. > > Btrfs workqueues can slow sensitive user tasks down because they can use > any online CPU to perform heavy workloads on an SMP system. Add a mount > option to isolate the Btrfs workqueues to a set of CPUs. It is helpful > to avoid sensitive user tasks being preempted by Btrfs heavy workqueues. > > This option is similar to the taskset bitmask except that the comma > separator is replaced with a dot. The reason for this is that the mount > option parser uses commas to separate mount options. Hmm... the allowed cpumasks for unbounded workqueues can already be set through /sys/devices/virtual/workqueue/cpumask and also each individual workqueue can be exposed in the matching subdirectory by setting WQ_SYSFS. Wouldn't the proposed btrfs option be a bit reduandant? Thanks. -- tejun
