On Fri, Aug 7, 2020 at 9:03 AM Mike Snitzer <snitzer@xxxxxxxxxx> wrote:
>
> - DM crypt improvement to optionally avoid async processing via
> workqueues for reads and/or writes -- via "no_read_workqueue" and
> "no_write_workqueue" features. This more direct IO processing
> improves latency and throughput with faster storage. Avoiding
> workqueue IO submission for writes (DM_CRYPT_NO_WRITE_WORKQUEUE) is
> a requirement for adding zoned block device support to DM crypt.
Is there a reason the async workqueue isn't removed entirely if it's not a win?
Or at least made to not be the default.
Now it seems to be just optionally disabled, which seems the wrong way
around to me.
I do not believe async crypto has ever worked or been worth it.
Off-loaded crypto in the IO path, yes. Async using a workqueue? Naah.
Or do I misunderstand?
Linus
