Re: [PATCH v2 0/2] enable fsdax rdma migration

[address@hidden]

CCing  Marcel


On 23/08/2021 11:33, Li Zhijian wrote:
> Previous qemu are facing 2 problems when migrating a fsdax memory backend with
> RDMA protocol.
> (1) ibv_reg_mr failed with Operation not supported
> (2) requester(source) side could receive RNR NAK.
>
> For the (1), we can try to register memory region with ODP feature which
> has already been implemented in some modern HCA hardware/drivers.
> For the (2), IB provides advise API to prefetch pages in specific memory
> region. It can help driver reduce the page fault on responder(destination)
> side during RDMA_WRITE.
>
> CC: marcel.apfelbaum@gmail.com
>
> Li Zhijian (2):
>    migration/rdma: Try to register On-Demand Paging memory region
>    migration/rdma: advise prefetch write for ODP region
>
>   migration/rdma.c       | 117 +++++++++++++++++++++++++++++++++--------
>   migration/trace-events |   2 +
>   2 files changed, 98 insertions(+), 21 deletions(-)
>