Oh yeah, iirc, the 1M IOPS driver was a block driver. For the SCSI over PCIe stuff, there was the big problem at the time that the entire SCSI layer in the ker

Oh yeah, iirc, the 1M IOPS driver was a block driver. For the SCSI over PCIe stuff, there was the big problem at the time that the entire SCSI layer in the kernel was a bottleneck, so you could make the driver as fast as you wanted, but your requests were still coming through a single queue managed by locks, so you were screwed. There was a whole ton of work done by Christoph Hellwig, Jens Axboe and others to make the SCSI layer "multiqueue" around that time to fix that.