[ Trimmed Eric from CC list as vger was complaining that it is too long ]

On Tue, Jan 18, 2011 at 11:41:22AM -0800, Rick Jones wrote:

quoted

So it won't be all that simple to implement well, and before we try,
I'd like to know whether there are applications that are helped
by it. For example, we could try to measure latency at various
pps and see whether the backpressure helps. netperf has -b, -w
flags which might help these measurements.

Those options are enabled when one adds --enable-burst to the
pre-compilation ./configure  of netperf (one doesn't have to
recompile netserver).  However, if one is also looking at latency
statistics via the -j option in the top-of-trunk, or simply at the
histogram with --enable-histogram on the ./configure and a verbosity
level of 2 (global -v 2) then one wants the very top of trunk
netperf from:

Hi,

I have constructed a test where I run an un-paced  UDP_STREAM test in
one guest and a paced omni rr test in another guest at the same time.
Breifly I get the following results from the omni test..

1. Omni test only:		MEAN_LATENCY=272.00
2. Omni and stream test:	MEAN_LATENCY=3423.00
3. cpu and net_cls group:	MEAN_LATENCY=493.00
   As per 2 plus cgoups are created for each guest
   and guest tasks added to the groups
4. 100Mbit/s class:		MEAN_LATENCY=273.00
   As per 3 plus the net_cls groups each have a 100MBit/s HTB class
5. cpu.shares=128:		MEAN_LATENCY=652.00
   As per 4 plus the cpu groups have cpu.shares set to 128
6. Busy CPUS:			MEAN_LATENCY=15126.00
   As per 5 but the CPUs are made busy using a simple shell while loop

There is a bit of noise in the results as the two netperf invocations
aren't started at exactly the same moment

For reference, my netperf invocations are:
netperf -c -C -t UDP_STREAM -H 172.17.60.216 -l 12
netperf.omni -p 12866 -D -c -C -H 172.17.60.216 -t omni -j -v 2 -- -r 1 -d rr -k foo -b 1 -w 200 -m 200

foo contains
PROTOCOL
THROUGHPUT,THROUGHPUT_UNITS
LOCAL_SEND_THROUGHPUT
LOCAL_RECV_THROUGHPUT
REMOTE_SEND_THROUGHPUT
REMOTE_RECV_THROUGHPUT
RT_LATENCY,MIN_LATENCY,MEAN_LATENCY,MAX_LATENCY
P50_LATENCY,P90_LATENCY,P99_LATENCY,STDDEV_LATENCY
LOCAL_CPU_UTIL,REMOTE_CPU_UTIL