[openib-general] performance tests uploaded to contrib

[Michael S. Tsirkin]

Quoting r. Sayantan Sur <surs at cse.ohio-state.edu>:
> Subject: Re: [openib-general] performance tests uploaded to contrib
> 
> Michael S. Tsirkin wrote:
> >Quoting r. Sayantan Sur <surs at cse.ohio-state.edu>:
> >
> >>Subject: Re: [openib-general] performance tests uploaded to contrib
> >>
> >>Michael,
> >>
> >>
> >>>Current results:
> >>>
> >>>I currently observe latency below 3.5 usec.
> >>>
> >>>Drop me a note if you find this useful.
> >>
> >>Thanks for putting this up on the contrib tree. I have run this
> >>rdma_latency, and am getting around 3.35 us (without switch).
> >>
> >>Our platform is Dual Xeon EM64T with RH AS 4. Kernel version 2.6.11.7
> >>
> >>Do you have any idea when a port of the popular `perf_main' will be
> >>available? As more people try to use the Gen2 verbs, `perf_main' (or
> >>something similar) can help people evaluate different IB operations and
> >>also to have example code to use different features of IB.
> >>
> >>Thanks,
> >>Sayantan.
> >>
> >
> >
> >I dont plan to port the monolithic perf_main to gen2.
> >
> >Instead, I plan to upload a set of microbenchmarks each testing
> >a specific feature: rdma latency/rc send latency/rdma bandwidth/rc send
> >bandwidth etc.
> >
> >I hope that this will help achieve better code clarity than what we 
> >have in perf_main.
> 
> That is fine. As long as there is some ibverbs level benchmark suite, it 
> will ease the transition.
> 
> >
> >What are the features you are most interested in?
> 
> By RDMA latency/bandwidth, do you mean both RDMA write & read?

RDMA write test is out there, I hope to upload the read test RSN.

> Will 
> there be any Atomic latency tests also?

Sure, why not. Is it a priority for you?

> >
> >By the way, you can already see some example code in libibverbs/examples,
> >although that is not necessarily benchmark-oriented.
> >I used the code in pingpong.c as a starting point for rdma latency
> >test, and it can be used with very little changes as rc send latency
> >test.
> 
> Yes, this was helpful for me too. Apart from providing code examples, I 
> was suggesting that a much more comprehensive benchmark suite will help 
> people moving from other vendor stacks to Gen2 to have a quick 
> comparison of performance offered by both stacks.
> 
> Thanks,
> Sayantan.
> 

I agree.

-- 
MST - Michael S. Tsirkin