[Qemu-discuss] A question about virtio inside qemu

[Yaodong Yang]

Hi community,

I have a quick question about the virtio inside qemu. When the user application sends to a specific virtual disk a large number of read requests in a very short time, where should these requests be queued? Inside the virtqueue? virtqueue available ring or the underlying bdrv_read_aio()?

Currently, I run one guest vm with two virtual disks (one for ubuntu system, the other is to serve the data access.) When the system is running, I can check there are for instance 50 inflight requests to read or write the system virtual disk. However, the inflight requests to the data virtual disk is always one. Which is not reasonable, because inside the vm we calculated the avery response time for each request is much larger than the time interval between two adjacent requests.

My ultimate goal is to get the number of in-flight requests for a certain virtual disk. Could someone give me some hints?

Thanks a lot! I appreciate your help!

Yaodong