On 3/2/2020 7:43 PM, Sagi Grimberg wrote:

quoted

Hi Sagi & Max Gurtovoy,

Thanks for your pointers regarding mdts.

Looks like fixing this issue through mdts is more natural than fixing
through RDMA private data.

Issue is not occuring after appling the below patch(inspired by Max's
patch "nvmet-rdma: Implement set_mdts controller op").

So any consensus about merging the fix upstream, to fix this specific
issue?

I think we can do this asap.

Max, please send a patch for this.

sure, I'll do that.

But since nvmet/rdma uses RW API that may use multiple MR's per IO 
request we need to implement the set_mdts differently.

We need to update the value of max_rdma_ctxs that set the MR pool size. 
We can limit the RDMA transport to support upto 1 or 2 MB and get the 
factor we need for setting the max_rdma_ctxs.

I'll send a fix soon.

Thanks,