On 5/14/2020 9:18 PM, santosh.shilimkar@xxxxxxxxxx wrote:
On 5/14/20 8:13 AM, Aron Silverton wrote:
+Santosh
You probably meant to copy the RDS maintainer? Not sure if this
should have
also been sent to netdev@xxxxxxxxxxxxxxx.
Thanks Aron.
On May 14, 2020, at 7:02 AM, Max Gurtovoy <maxg@xxxxxxxxxxxx> wrote:
This series removes the support for FMR mode to register memory.
This ancient
mode is unsafe and not maintained/tested in the last few years. It
also doesn't
have any reasonable advantage over other memory registration methods
such as
FRWR (that is implemented in all the recent RDMA adapters). This
series should
be reviewed and approved by the maintainer of the effected drivers
and I
suggest to test it as well.
I know the security issue has been brought up before and this plan of
removal of FMR support was on the cards but on RDS at least on CX3 we
got more throughput with FMR vs FRWR. And the reasons are well
understood as well why its the case.
Please share the benchmark for both and the reasons that you understood
for the difference.
We'll try to analyze how to improve ConnectX-3 FRWR
Is it possible to keep core support still around so that HCA's which
supports FMR, ULPs can still can leverage it if they want.
From RDS perspective, if the HCA like CX3 doesn't support both modes,
code prefers FMR vs FRWR and hence the question.
Well this series delete around 2400-2500 LOC that are probably almost
not used and tested.
Lets try to understand the perf degradation.
Also while re-posting the series, please copy me on the patches.
Sure.
Regards,
Santosh
