On Sat, Aug 06, 2022 at 09:20:03AM -0600, Jens Axboe wrote:
bdev based polled O_DIRECT is currently quite a bit faster than
passthru on the same device, and one of the reaons is that we're not
able to use the bio caching for passthru IO.
If REQ_POLLED is set on the request, use the fs bio set for grabbing a
bio from the caches, if available. This saves 5-6% of CPU over head
for polled passthru IO.
For passthru path, bio is always freed in the task-context (and not in
irq) so must this be tied to polled-io only?
