Re: [Qemu-devel] [PATCH v11 10/15] rdma: introduce capability x-rdma-pin-all

[Juan Quintela]

address@hidden wrote:
> From: "Michael R. Hines" <address@hidden>
>
> This capability allows you to disable dynamic chunk registration
> for better throughput on high-performance links.
>
> For example, using an 8GB RAM virtual machine with all 8GB of memory in
> active use and the VM itself is completely idle using a 40 gbps infiniband 
> link:
>
> 1. x-rdma-pin-all disabled total time: approximately 7.5 seconds @ 9.5 Gbps
> 2. x-rdma-pin-all enabled total time: approximately 4 seconds @ 26 Gbps
>
> These numbers would of course scale up to whatever size virtual machine
> you have to migrate using RDMA.
>
> Enabling this feature does *not* have any measurable affect on
> migration *downtime*. This is because, without this feature, all of the
> memory will have already been registered already in advance during
> the bulk round and does not need to be re-registered during the successive
> iteration rounds.
>
> Reviewed-by: Paolo Bonzini <address@hidden>
> Reviewed-by: Chegu Vinod <address@hidden>
> Reviewed-by: Eric Blake <address@hidden>
> Tested-by: Chegu Vinod <address@hidden>
> Tested-by: Michael R. Hines <address@hidden>
> Signed-off-by: Michael R. Hines <address@hidden>

Reviewed-by: Juan Quintela <address@hidden>