Hi James- > On Aug 18, 2016, at 12:09 AM, james harvey <jamespharvey20@xxxxxxxxx> wrote: > > A year ago, on 7/30/2015, Chuck Lever said NFS/RDMA wasn't yet working > with NFSv4.1 and NFSv4.2, as a known issue. > > I was able to use "vers=4.0" to get around the issue. > > I see v4.2 seems to mount properly, but before switching over to it, I > wanted to see if it's considered stable, or still to be avoided. Can you tell why you'd like to use it? Which NFSv4.2 feature is interesting to you? I don't test it regularly, simply because - The complete tests on each version take a long time to run - NFSv4.2 features are all optional, and the Linux NFSv4.2 implementation adds only a couple that probably won't be affected by RDMA. READ_PLUS will need some attention at some point, but I think Anna is still polishing the upper layer implementation. - I don't have any specific tests for security labels, which add to the size of the NFSv4 GETATTR receive buffer whether labels are actually retrieved or not. So there is a little NFSv4.2 testing we get for free just by using NFSv4.0. - There's yet a lot of non-version-specific work to do on RPC-over-RDMA. The main blocker before was support for bi-directional RPC, which all minorversions of NFSv4 use after mv 1, and that should be working as well as it does for NFSv4.1. NFSv4.2 itself should work, but I might choose to stay with NFSv4.1 for now if it were up to me, unless you have need of one of the new features. For example, there is no standard specification describing how READ_PLUS is supposed to work on RPC-over-RDMA (that's in the works). -- Chuck Lever -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
