Re: [Qemu-devel] [PATCH v1 0/2] Add live migration support in the PVRDMA device

[Yuval Shaia]

On Wed, Aug 28, 2019 at 07:53:26PM +0530, Sukrit Bhatnagar wrote:
> This series enables the migration of various GIDs used by the device.    
> This is in addition to the successful migration of PCI and MSIX states
> as well as various DMA addresses and ring page information.
>     
> We have a setup having two hosts and two VMs running atop them.    
> Migrations are performed over the local network.    
> 
> We also have performed various ping-pong tests (ibv_rc_pingpong) in the    
> guest(s) after adding GID migration support and this is the current status:   
>  
> - ping-pong to localhost succeeds, when performed before starting the    
>   migration and after the completion of migration.    
> - ping-pong to a peer succeeds, both before and after migration as above,    
>   provided that both VMs are running on/migrated to the same host.    
>   So, if two VMs were started on two different hosts, and one of them    
>   was migrated to the other host, the ping-pong was successful.    

This limitation looks to me like wrongly configured network. This patch-set
should enable any migration.

After our last meeting, please confirm.

In addition, i don't see why non-VM peer (i.e. Bare-metal) is not
supported. Can you run a test and update with the results?

>   Similarly, if two VMs are migrated to the same host, then after migration,  
>   
>   the ping-pong was successful.    
> - ping-pong to a peer on the remote host is not working as of now.    
>     
> Our next goal is to achieve successful migration with live traffic.    
>     
> This is the same as the RFC v3 series posted earlier:
> https://lists.gnu.org/archive/html/qemu-devel/2019-07/msg04752.html
> https://lists.gnu.org/archive/html/qemu-devel/2019-07/msg04753.html
> https://lists.gnu.org/archive/html/qemu-devel/2019-07/msg04754.html
> 
> 
> Sukrit Bhatnagar (2):
>   hw/pvrdma: make DSR mapping idempotent in load_dsr()
>   hw/pvrdma: add live migration support
> 
>  hw/rdma/vmw/pvrdma_main.c | 94 +++++++++++++++++++++++++++++++++++----
>  1 file changed, 86 insertions(+), 8 deletions(-)
> 
> -- 
> 2.21.0
> 
>