Re: [PATCH-for-9.1 v2 2/3] migration: Remove RDMA protocol handling

[Zhijian Li (Fujitsu)]

on 4/10/2024 3:46 AM, Peter Xu wrote:

>> Is there document/link about the unittest/CI for migration tests, Why
>> are those tests missing?
>> Is it hard or very special to set up an environment for that? maybe we
>> can help in this regards.
> See tests/qtest/migration-test.c.  We put most of our migration tests
> there and that's covered in CI.
>
> I think one major issue is CI systems don't normally have rdma devices.
> Can rdma migration test be carried out without a real hardware?

Yeah,  RXE aka. SOFT-RoCE is able to emulate the RDMA, for example
$ sudo rdma link add rxe_eth0 type rxe netdev eth0  # on host
then we can get a new RDMA interface "rxe_eth0".
This new RDMA interface is able to do the QEMU RDMA migration.

Also, the loopback(lo) device is able to emulate the RDMA interface 
"rxe_lo", however when
I tried(years ago) to do RDMA migration over this 
interface(rdma:127.0.0.1:3333) , it got something wrong.
So i gave up enabling the RDMA migration qtest at that time.



Thanks
Zhijian



     

>
>>> It seems there can still be people joining this discussion.  I'll hold off
>>> a bit on merging this patch to provide enough window for anyone to chim in.
>> Thx for discussion and understanding.
> Thanks for all these inputs so far.  These can help us make a wiser and
> clearer step no matter which way we choose.