On Wed, Apr 8, 2015 at 2:06 AM, Luigi Rizzo <ri...@iet.unipi.it> wrote:
On Tue, Apr 7, 2015 at 6:54 PM, Alexander Graf <ag...@suse.de> wrote:
On 04/01/2015 10:15 AM, Jason Wang wrote:
This patch increases the maximum number of virtqueues for pci from
64
to 513. This will allow booting a virtio-net-pci device with 256
queue
pairs.
...
* configuration space */
#define VIRTIO_PCI_CONFIG_SIZE(dev)
VIRTIO_PCI_CONFIG_OFF(msix_enabled(dev))
-#define VIRTIO_PCI_QUEUE_MAX 64
+#define VIRTIO_PCI_QUEUE_MAX 513
513 is an interesting number. Any particular reason for it? Maybe
this was mentioned before and I just missed it ;)
quite large, too. I thought multiple queue pairs were useful
to split the load for multicore machines, but targeting VMs with
up to 256 cores (and presumably an equal number in the host)
seems really forward looking.
Probably not, since KVM can support up to 255 vcpus now.
On the other hand, the message is dated april first...
cheers
luigi
