[PATCH RFC v1 0/5] Add SCSI per device tagsets

[Christoph Hellwig]

On Fri, Feb 18, 2022 at 06:41:52PM +0000, Melanie Plageman (Microsoft) wrote:
> Currently a single blk_mq_tag_set is associated with a Scsi_Host. When SCSI
> controllers are limited, attaching multiple devices to the same controller is
> required. In cloud environments with relatively high latency persistent storage,
> requiring all devices on a controller to share a single blk_mq_tag_set
> negatively impacts performance.

So add more controllers instead of completely breaking the architecture.