Messages in this thread | | | Date | Mon, 24 Nov 2014 13:46:50 -0500 (EST) | From | Pankaj Gupta <> | Subject | Re: [PATCH v2 net-next 3/3] tuntap: Increase the number of queues in tun. |
| |
Adding Michael to CC.
> > Networking under kvm works best if we allocate a per-vCPU RX and TX > queue in a virtual NIC. This requires a per-vCPU queue on the host side. > > It is now safe to increase the maximum number of queues. > Preceding patches: > net: allow large number of rx queues > tuntap: Reduce the size of tun_struct by using flex array > > made sure this won't cause failures due to high order memory > allocations. Increase it to 256: this is the max number of vCPUs > KVM supports. > > Signed-off-by: Pankaj Gupta <pagupta@redhat.com> > Reviewed-by: David Gibson <dgibson@redhat.com> > --- > drivers/net/tun.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c > index e3fa65a..a19dc5f8 100644 > --- a/drivers/net/tun.c > +++ b/drivers/net/tun.c > @@ -113,10 +113,11 @@ struct tap_filter { > unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN]; > }; > > -/* DEFAULT_MAX_NUM_RSS_QUEUES were chosen to let the rx/tx queues allocated > for > - * the netdevice to be fit in one page. So we can make sure the success of > - * memory allocation. TODO: increase the limit. */ > -#define MAX_TAP_QUEUES DEFAULT_MAX_NUM_RSS_QUEUES > +/* MAX_TAP_QUEUES 256 is chosen to allow rx/tx queues to be equal > + * to max number of vCPUS in guest. Also, we are making sure here > + * queue memory allocation do not fail. > + */ > +#define MAX_TAP_QUEUES 256 > #define MAX_TAP_FLOWS 4096 > > #define TUN_FLOW_EXPIRE (3 * HZ) > -- > 1.8.3.1 > >
| |