On Thu, Dec 07, 2023 at 12:31:05PM +0800, Li Feng wrote: > virtio-blk is generally used in cloud computing scenarios, where the > performance of virtual disks is very important. The mq-deadline scheduler > has a big performance drop compared to none with single queue. In my tests, > mq-deadline 4k readread iops were 270k compared to 450k for none. So here > the default scheduler of virtio-blk is set to "none". The test result shows you may not test HDD. backing of virtio-blk. none can lose IO merge capability more or less, so probably sequential IO perf drops in case of HDD backing. Thanks, Ming