Can we increase vring size over 1024?

Gonglei (Arei)
2016-09-02T06:55:58Z

Hi Michael & all,

Michael, you made a presentation about the virto 1.1's new features in KVM Forum last week.
That's wonderful!

And I'd like to know can we increase vring size over 1024, such as 4096 or 8192?

My colleage had asked the same question in 2014, but she didn't get a definite answare,
So, I want to rewake up the dissusstion about this. Becase for the virtio-crypto device,
I also need to increase the vring size to get better performance and thoughput, but the Qemu
side limit the thought as VIRTQUEUE_MAX_SIZE is 1024.

[QA-virtio]:Why vring size is limited to 1024?
http://qemu.11.n7.nabble.com/QA-virtio-Why-vring-size-is-limited-to-1024-td292450.html

Avi Kivity said that google cloud exposed the vring size to 16k.

Regards,
-Gonglei