* Re: [dpdk-users] VHOST-USER interface between ovs-dpdk and a VM
@ 2017-05-23 15:16 Avi Cohen (A)
0 siblings, 0 replies; 2+ messages in thread
From: Avi Cohen (A) @ 2017-05-23 15:16 UTC (permalink / raw)
To: users
Sorry - step 4 below is incorrect:
There is a copy between guest OS and guest user-space.
Now the question is - what is the different of # of copies (copies of packet from host to guest application) between this setup (OVS-DPDK) and setup with standard OVS (no dpdk)
Best regards
> -----Original Message-----
> From: Avi Cohen (A)
> Sent: Tuesday, 23 May, 2017 4:27 PM
> To: users@dpdk.org
> Subject: VHOST-USER interface between ovs-dpdk and a VM
>
> Hi,
> I'm trying to understand the packet life-cycle in ovs-dpdk (running on host)
> communicating with a VM through vhost-user interface:
> 1. packet is received via physical port to the device.
> 2.DMA transfer to mempools on huge-pages allocated by dpdk-ovs - in user-
> space.
> 3. ovs-dpdk copies this packet to the shared-vring of the associated guest
> (shared between ovs-dpdk userspace process and guest)
[Avi Cohen (A)]
4. no more copies in
> the guest - i.e. when any application running on the guest wants to consume the
> packet - there is a zero copy between the shared-vring and the guest
> application.
>
> Is that correct ? how 4 is implemented ? this is a communication between OS
> in guest and application in guest . so how this is implemented with zero copy ?
>
> Best Regards
> avi
^ permalink raw reply [flat|nested] 2+ messages in thread
* [dpdk-users] VHOST-USER interface between ovs-dpdk and a VM
@ 2017-05-23 13:27 Avi Cohen (A)
0 siblings, 0 replies; 2+ messages in thread
From: Avi Cohen (A) @ 2017-05-23 13:27 UTC (permalink / raw)
To: users
Hi,
I'm trying to understand the packet life-cycle in ovs-dpdk (running on host) communicating with a VM through vhost-user interface:
1. packet is received via physical port to the device.
2.DMA transfer to mempools on huge-pages allocated by dpdk-ovs - in user-space.
3. ovs-dpdk copies this packet to the shared-vring of the associated guest (shared between ovs-dpdk userspace process and guest)
4. no more copies in the guest - i.e. when any application running on the guest wants to consume the packet - there is a zero copy between the shared-vring and the guest application.
Is that correct ? how 4 is implemented ? this is a communication between OS in guest and application in guest . so how this is implemented with zero copy ?
Best Regards
avi
^ permalink raw reply [flat|nested] 2+ messages in thread
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