From: Jason Wang <hidden> Date: 2015-10-23 04:57:13
We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.
With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.
Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <redacted>
---
drivers/net/macvtap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
From: David Miller <davem@davemloft.net> Date: 2015-10-23 09:19:04
From: Jason Wang <redacted>
Date: Fri, 23 Oct 2015 00:57:05 -0400
We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.
With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.
Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <redacted>
From: "Michael S. Tsirkin" <mst@redhat.com> Date: 2015-10-23 13:37:42
On Fri, Oct 23, 2015 at 12:57:05AM -0400, Jason Wang wrote:
We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.
With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.
Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <redacted>
Thanks!
Does this mean we should look at re-adding NETIF_F_FRAGLIST
to virtio-net as well?
From: Jason Wang <hidden> Date: 2015-10-26 03:16:05
On 10/23/2015 09:37 PM, Michael S. Tsirkin wrote:
On Fri, Oct 23, 2015 at 12:57:05AM -0400, Jason Wang wrote:
quoted
We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.
With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.
Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <redacted>
Thanks!
Does this mean we should look at re-adding NETIF_F_FRAGLIST
to virtio-net as well?
Not sure I get the point, but probably not. This is for receiving and
skb_copy_datagram_iter() can deal with frag list.
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From: "Michael S. Tsirkin" <mst@redhat.com> Date: 2015-10-26 06:09:35
On Mon, Oct 26, 2015 at 11:15:57AM +0800, Jason Wang wrote:
On 10/23/2015 09:37 PM, Michael S. Tsirkin wrote:
quoted
On Fri, Oct 23, 2015 at 12:57:05AM -0400, Jason Wang wrote:
quoted
We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.
With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.
Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <redacted>
Thanks!
Does this mean we should look at re-adding NETIF_F_FRAGLIST
to virtio-net as well?
Not sure I get the point, but probably not. This is for receiving and
skb_copy_datagram_iter() can deal with frag list.
Point is:
- bridge within guest
- assigned device creating gro skbs with frag list bridged to virtio
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the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Jason Wang <hidden> Date: 2015-10-26 06:53:46
On 10/26/2015 02:09 PM, Michael S. Tsirkin wrote:
On Mon, Oct 26, 2015 at 11:15:57AM +0800, Jason Wang wrote:
quoted
On 10/23/2015 09:37 PM, Michael S. Tsirkin wrote:
quoted
On Fri, Oct 23, 2015 at 12:57:05AM -0400, Jason Wang wrote:
quoted
We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.
With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.
Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <redacted>
Thanks!
Does this mean we should look at re-adding NETIF_F_FRAGLIST
to virtio-net as well?
Not sure I get the point, but probably not. This is for receiving and
skb_copy_datagram_iter() can deal with frag list.
Point is:
- bridge within guest
- assigned device creating gro skbs with frag list bridged to virtio
I see, but this problem looks not specific to virtio. Most cards does
not support frag list.
From: "Michael S. Tsirkin" <mst@redhat.com> Date: 2015-10-26 08:30:27
On Mon, Oct 26, 2015 at 02:53:38PM +0800, Jason Wang wrote:
On 10/26/2015 02:09 PM, Michael S. Tsirkin wrote:
quoted
On Mon, Oct 26, 2015 at 11:15:57AM +0800, Jason Wang wrote:
quoted
On 10/23/2015 09:37 PM, Michael S. Tsirkin wrote:
quoted
On Fri, Oct 23, 2015 at 12:57:05AM -0400, Jason Wang wrote:
quoted
We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.
With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.
Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <redacted>
Thanks!
Does this mean we should look at re-adding NETIF_F_FRAGLIST
to virtio-net as well?
Not sure I get the point, but probably not. This is for receiving and
skb_copy_datagram_iter() can deal with frag list.
Point is:
- bridge within guest
- assigned device creating gro skbs with frag list bridged to virtio
I see, but this problem looks not specific to virtio. Most cards does
not support frag list.
These will be slower when used with a bridge then, won't they?
--
MST
From: Jason Wang <hidden> Date: 2015-10-27 02:58:32
On 10/26/2015 04:30 PM, Michael S. Tsirkin wrote:
On Mon, Oct 26, 2015 at 02:53:38PM +0800, Jason Wang wrote:
quoted
On 10/26/2015 02:09 PM, Michael S. Tsirkin wrote:
quoted
On Mon, Oct 26, 2015 at 11:15:57AM +0800, Jason Wang wrote:
quoted
On 10/23/2015 09:37 PM, Michael S. Tsirkin wrote:
quoted
On Fri, Oct 23, 2015 at 12:57:05AM -0400, Jason Wang wrote:
quoted
We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.
With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.
Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <redacted>
Thanks!
Does this mean we should look at re-adding NETIF_F_FRAGLIST
to virtio-net as well?
Not sure I get the point, but probably not. This is for receiving and
skb_copy_datagram_iter() can deal with frag list.
Point is:
- bridge within guest
- assigned device creating gro skbs with frag list bridged to virtio
I see, but this problem looks not specific to virtio. Most cards does
not support frag list.
These will be slower when used with a bridge then, won't they?
For forwarding, not sure. GRO has latency and cpu overhead anyway.
Anyway I can try to add the support for this.
From: "Michael S. Tsirkin" <mst@redhat.com> Date: 2015-10-27 09:05:55
On Tue, Oct 27, 2015 at 10:58:25AM +0800, Jason Wang wrote:
On 10/26/2015 04:30 PM, Michael S. Tsirkin wrote:
quoted
On Mon, Oct 26, 2015 at 02:53:38PM +0800, Jason Wang wrote:
quoted
On 10/26/2015 02:09 PM, Michael S. Tsirkin wrote:
quoted
On Mon, Oct 26, 2015 at 11:15:57AM +0800, Jason Wang wrote:
quoted
On 10/23/2015 09:37 PM, Michael S. Tsirkin wrote:
quoted
On Fri, Oct 23, 2015 at 12:57:05AM -0400, Jason Wang wrote:
quoted
We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.
With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.
Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <redacted>
Thanks!
Does this mean we should look at re-adding NETIF_F_FRAGLIST
to virtio-net as well?
Not sure I get the point, but probably not. This is for receiving and
skb_copy_datagram_iter() can deal with frag list.
Point is:
- bridge within guest
- assigned device creating gro skbs with frag list bridged to virtio
I see, but this problem looks not specific to virtio. Most cards does
not support frag list.
These will be slower when used with a bridge then, won't they?
For forwarding, not sure. GRO has latency and cpu overhead anyway.
Right but that's up to the user. You aren't disabling GRO
on source, you are just splitting it up.
Anyway I can try to add the support for this.
Which reminds me: on modern devices there are commands to control
offloads, so for these, we should support turning offloads on/off using
ethtool.
--
MST
From: Jason Wang <hidden> Date: 2015-10-28 02:51:25
On 10/27/2015 05:05 PM, Michael S. Tsirkin wrote:
On Tue, Oct 27, 2015 at 10:58:25AM +0800, Jason Wang wrote:
quoted
On 10/26/2015 04:30 PM, Michael S. Tsirkin wrote:
quoted
On Mon, Oct 26, 2015 at 02:53:38PM +0800, Jason Wang wrote:
quoted
On 10/26/2015 02:09 PM, Michael S. Tsirkin wrote:
quoted
On Mon, Oct 26, 2015 at 11:15:57AM +0800, Jason Wang wrote:
quoted
On 10/23/2015 09:37 PM, Michael S. Tsirkin wrote:
quoted
On Fri, Oct 23, 2015 at 12:57:05AM -0400, Jason Wang wrote:
quoted
We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.
With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.
Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <redacted>
Thanks!
Does this mean we should look at re-adding NETIF_F_FRAGLIST
to virtio-net as well?
Not sure I get the point, but probably not. This is for receiving and
skb_copy_datagram_iter() can deal with frag list.
Point is:
- bridge within guest
- assigned device creating gro skbs with frag list bridged to virtio
I see, but this problem looks not specific to virtio. Most cards does
not support frag list.
These will be slower when used with a bridge then, won't they?
For forwarding, not sure. GRO has latency and cpu overhead anyway.
Right but that's up to the user. You aren't disabling GRO
on source, you are just splitting it up.
quoted
Anyway I can try to add the support for this.
Which reminds me: on modern devices there are commands to control
offloads, so for these, we should support turning offloads on/off using
ethtool.
Trying to implement frag list but see a problem. Looks like driver need
to scan the possible number of io vectors? (Since vhost support max to
UIO_MAXIOV number of io vectors). Looks like there's no clarification on
this in the spec. (Which only limit the length of descriptor chain to
Queue size).