Hi Jason, On 1/18/21 1:25 PM, Jason Wang wrote: > > On 2021/1/18 上午11:58, Joseph Qi wrote: >> module parameter 'virtblk_queue_depth' was firstly introduced for >> testing/benchmarking purposes described in commit fc4324b4597c >> ("virtio-blk: base queue-depth on virtqueue ringsize or module param"). >> Since we have different virtio-blk devices which have different >> capabilities, it requires that we support per-device queue depth instead >> of per-module. So defaultly use vq free elements if module parameter >> 'virtblk_queue_depth' is not set. > > > I wonder if it's better to use sysfs instead (or whether it has already had something like this in the blocker layer). > Thanks for quick response. Do you mean adjust /sys/block/vdX/queue/nr_requests? But current logic in virtblk_probe() is, virtblk_queue_depth is used as a saved value for first probed vdev, not purely module parameter. Thanks, Joseph