[openib-general] question on QoS support

[Oliver]

Hi, Hal -

> How is this being observed/measured ?

Host A, B, with 4x DDR both connected to Flextronic switch.
A single process of ibv_read_bw gives about 1415MB /s average
bandwidth. Two concurrent process report 714.45 MB/s each, dead even.
Now if I bump up one process with a different SL, then I expect to see
shaping to take place. Please let me if the scenario makes sense.



> Yes, 8 VLs should be supported in your subnet. You can verify this with
> smpquery portinfo on the HCA port and examine OperVLs assuming the port
> is ACTIVE.

yes, I verified the data VL support, it is 8. I will poke for more
info with suggested commands by Sasha.

> > A related question is, if I modify qos setting in SM, do I need to
> > restart SA on each hosts for it to see the changes? (I am hoping not,
> > as I tried in the test, it doesn't seem to make a difference)
>
> Not sure what you mean. SA is tightly coupled with the OpenSM. Do you
> mean SA client ? The client hosts don't need restarting but did you
> restart OpenSM with your QoS configuration ?

I mean client SA. yes, I understand OpenSM needs to be restarted.

> BTW, which OpenSM are you running ?

OFED 1.1 based.

thanks

- Oliver