Hi Sagi & Max,
Any update on this?
Please change the max IO size to 1MiB(256 pages).
I think that the reason why this was changed to handle the worst case
was in case there are different capabilities on the initiator and the
target with respect to number of pages per MR. There is no handshake
that aligns expectations.
If we revert that it would restore the issue that you reported in the
first place:
--
IB/isert: allocate RW ctxs according to max IO size
Current iSER target code allocates MR pool budget based on queue size.
Since there is no handshake between iSER initiator and target on max IO
size, we'll set the iSER target to support upto 16MiB IO operations and
allocate the correct number of RDMA ctxs according to the factor of MR's
per IO operation. This would guaranty sufficient size of the MR pool for
the required IO queue depth and IO size.
Reported-by: Krishnamraju Eraparaju <krishna2@xxxxxxxxxxx>
Tested-by: Krishnamraju Eraparaju <krishna2@xxxxxxxxxxx>
Signed-off-by: Max Gurtovoy <maxg@xxxxxxxxxxxx>
--
Thanks,
Krishnam Raju.
On Wednesday, September 09/23/20, 2020 at 01:57:47 -0700, Sagi Grimberg wrote:
Hi,
Please reduce the Max IO size to 1MiB(256 pages), at iSER Target.
The PBL memory consumption has increased significantly after increasing
the Max IO size to 16MiB(with commit:317000b926b07c).
Due to the large MR pool, the max no.of iSER connections(On one variant
of Chelsio cards) came down to 9, before it was 250.
NVMe-RDMA target also uses 1MiB max IO size.
Max, remind me what was the point to support 16M? Did this resolve
an issue?
