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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hey folks,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m wondering what the maximum rate of messages/sec
people are seeing on their spread networks. I’ve used the spflood
utility to test a few scenarios, and so far the best throughput I’ve seen
on production quality hardware ranges from 35,000 – 101,000 spread
messages/second. I can’t really tell if these numbers are high or low
compared to other users… The basics of this test are: 3 nodes in the
cluster, on gigE on a switch, with plenty of CPU. The limiting factor seems to
be CPU usage by the spread daemon itself. It appears to be a single-threaded
process, so the spflood testing causes spread to consume 100% cpu. The
bottleneck is messages/sec, not bytes/sec, for small message sizes.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Are there any recent measurements showing performance
statistics on modern CPUs and networking gear with various message sizes and #
of listeners, for different environments of LAN, and LAN+WAN segments?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>From what spflood testing is showing, so far, I believe the
limiting factor for me is not bandwidth, but messages/sec (pkts/sec). I
suspect I will have to use larger batched messages in my application to avoid
maxing out CPU on spread messages/sec (if I directly map application
message/sec to spread message/sec.)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m also interested in the performance of spread in
the face of some known likely failure conditions, like a single node being
down, or the leader down going down. Aside from a temporary spike in message
latency, I’m really interested in what effect a single dead-node will
have on overall throughput (msgs/sec) in a spread network. This obviously
translates directly to real world failure cases.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>What is your experience and do you have any tips to help
avoid overwhelming spread, and how to best implement clients (rotoring and
such) to reduce impact of likely failure cases?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Just curious… Thanks everyone, and thanks to Yair and
Co. for providing such an amazing framework like Spread.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>- Will</span></font><o:p></o:p></p>
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