On Fri, Nov 11, 2016 at 04:46:34PM +0100, Hannes Reinecke wrote: > This patch enables full scsi-mq support for the hpsa driver. > Due to some reports of performance regressions this patch > also adds a parameter 'use_blk_mq' which can be used to > disable multiqueue support if required. This patch looks odd to me. The hardware does not seem to support multiple submission queues, which makes exposing nr_hw_queues > 1 rather pointless given that the block layer (using blk-mq or the legacy path) can already steer completions to the submitting cpu. You also mention there are performance regressions, but don't talk about any benefits. I also think per-driver module parameters for this are generally a rather bad idea. So what exactly are the benefits of this MQ-mode for a single submission queue device, and what do we need to do to get these without lying about the number of submission queues? -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
