On 12/04/2014 06:20 PM, Michael S. Tsirkin wrote: > On Thu, Dec 04, 2014 at 03:03:34AM +0008, Jason Wang wrote: >> > >> > >> > On Wed, Dec 3, 2014 at 5:52 PM, Michael S. Tsirkin <m...@redhat.com> wrote: >>> > >On Wed, Dec 03, 2014 at 12:49:37PM +0530, Pankaj Gupta wrote: >>>> > >> 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 patche: 'net: allow large number of rx queues' >>> > > >>> > >s/patche/patch/ >>> > > >>>> > >> 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 <pagu...@redhat.com> >>>> > >> Reviewed-by: David Gibson <dgib...@redhat.com> >>> > > >>> > >Hmm it's kind of nasty that each tun device is now using x16 memory. >>> > >Maybe we should look at using a flex array instead, and removing the >>> > >limitation altogether (e.g. make it INT_MAX)? >> > >> > But this only happens when IFF_MULTIQUEUE were used. > I refer to this field: > struct tun_file __rcu *tfiles[MAX_TAP_QUEUES]; > if we make MAX_TAP_QUEUES 256, this will use 4K bytes, > apparently unconditionally. > >
How about just allocate one tfile if IFF_MULTIQUEUE were disabled? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
