[openib-general] Re: Re: user-mode verbs on Itanium

[Grant Grundler]

On Wed, May 04, 2005 at 10:09:10AM +0300, Michael S. Tsirkin wrote:
> Grant, if you want a latency benchmark you may want to look at
> contrib/mellanox/perftest.

Notes on finding perftest
-------------------------

[ ggg *hugs* google ]

	http://article.gmane.org/gmane.linux.drivers.openib/9614

The SVN layout is confusing me.
I was expecting perftest in either svn/gen1/trunk or svn/gen2/trunk.

[ And there is also trunk/openib/gen1.
  Is that the same thing as svn/gen1?  ]

Would it make sense to move rdma_lat.c to gen2/trunk/src/userspace/examples ?
I only suggest it because the perftest/README says:
	This directory includes gen2 uverbs microbenchmarks -
	...



Building rmda_lat.c
-------------------
In order to compile on ia64, I had to hack:
	o use asm/timex.h to get arch specific cycles_t and get_cycles
	o ditch get_clock and use get_cycles instead
	o renamed get_clock.h into get_clock.c since it only contains C code
	o rewrite Makefile so it knew to build/link get_clock.o

I also rewrote the README so it's easier to read and list which
libs/headers rdma_lat depends on to build.

Since the diff is essentially the whole file for everything but
rdma_lat.c, I've parked the entire mess here:
	http://gsyprf3.external.hp.com/openib/perftest-01.tgz


BTW, Can I "leverage" code from ibv_pingpong to replace the issues
the following comment in rdma_lat.c refers to?
/*
 * pp_get_local_lid() uses a pretty bogus method for finding the LID
 * of a local port.  Please don't copy this into your app (or if you
 * do, please rip it out soon).
 */


rdma_lat runtime error
----------------------

Unlike ibv_pingpong, rdma_lat doesn't work and I'm hoping it might
be obvious to someone else why not. If it's not obvious, I can dig
deeper into it.  The two sides are able to identify each other but
call to ibv_post_send() failed on the first attempt.

"Server" side output:
grundler at gsyprf3:/usr/src/trunk/contrib/mellanox/perftest$ ./rdma_lat -s 64 -n 10000
  local address:  LID 0x0b, QPN 0x1b0406, PSN 0xdcf5cc RKey 0x1100032 VAddr 0x6000000000014040
  remote address: LID 0x10, QPN 0x30406, PSN 0x15f97c, RKey 0x1e0436 VAddr 0x6000000000014040

"Client" side output:
grundler at iota:/usr/src/trunk/contrib/mellanox/perftest$ ./rdma_lat -s 64 -n 10000 10.0.0.51
  local address:  LID 0x10, QPN 0x30406, PSN 0x15f97c RKey 0x1e0436 VAddr 0x6000000000014040
  remote address: LID 0x0b, QPN 0x1b0406, PSN 0xdcf5cc, RKey 0x1100032 VAddr 0x6000000000014040
Couldn't post send: scnt=1
grundler at iota:/usr/src/trunk/contrib/mellanox/perftest$ 

thanks,
grant