Re: [ofa-general] InfiniBand/iWARP/RDMA merge plans for 2.6.26 (what'sininfiniband.git)

From: Richard Frank
Date: Wed Apr 02 2008 - 13:01:55 EST


OK - and the conversation was about using NetPerf to compare performance of RDS to UDP relative to suitability for Oracle use ... so I think those statements still illustrate my points...

1) NetPerf does not do what Oracle does - and hence is not useful from Oracle's perspective in comparing ULPs.
2) For some metrics - it's not valid to compare a non-reliable IPC to a reliable IPC - it's not an apples to apples comparison. Especially when the app is considered and what the app must do to use UDP vs RDS.

I did not say that NetPerf should not be extended to support RDS - just that using it to do a comparison of ULPs to determine how well Oracle would run - is not what we (Oracle) would want - at least that was my intention..

Scott Weitzenkamp (sweitzen) wrote:
Rich,

On Nov 1, 2007, you wrote this to rds-devel:

"Netperf is too simplistic in that all it seems to do is stream data
in a simple loop. This is not how Oracle uses the IPC and again does not reflect what it would take to make UDP reliable.

For this reason we are not interested in having Netperf support RDS
and or seeing Netperf data."

I would like to see RDS supported by existing common tools like netperf,
iperf, etc. so we can easily compare how RDS performs to UDP for IPC
models other than Oracle.

Scott Weitzenkamp
SQA and Release Manager
Data Center Access Engineering
Cisco Systems




-----Original Message-----
From: Richard Frank [mailto:richard.frank@xxxxxxxxxx] Sent: Wednesday, April 02, 2008 10:38 AM
To: Scott Weitzenkamp (sweitzen)
Cc: Roland Dreier (rdreier); rds-devel@xxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; general@xxxxxxxxxxxxxxxxxxxxx
Subject: Re: [ofa-general] InfiniBand/iWARP/RDMA merge plans for 2.6.26 (what'sin infiniband.git)

I believe there is a patch for NetPerf which supports RDS - although it may need to be updated - and submitted.

The only prior discussion I can think of - was whether or not NetPerf exercises RDS as Oracle would.

I'm not proposing that we should enhance NetPerf to do that (but that's OK with me).

We created a tool rds-stress which does that.

Scott Weitzenkamp (sweitzen) wrote:
WRT to merging RDS into the kernel - our current plans are
to wait to
see RDS adopted by more than Oracle - before approaching
the kernel
community about inclusion of RDS.
I've seen statements before from someone from Oracle that
RDS was only
for Oracle's use, for example, that person did not want
netperf changed
to support RDS.

Scott Weitzenkamp
SQA and Release Manager
Data Center Access Engineering
Cisco Systems
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