Re: Performance?

[jerry.westrick at ch.abnamro.com]

I was thinking about your performance.
Could it be that network latency (round trip time)
is holding back your system?

Could it be that your communications protocol is
"synchish" instead of "asyncish"?

Let me explain what I mean:

"Syncish"
TIME   Client X  xmlBlaster
-----  --------  ----------
  ?         ?         ?
  ?         ?<--msg 1-+
  ?       proc1       ?
  ?         +-msg1ok->?
  ?         ?<--msg 2-+
  ?       proc2       ?
  ?         +-msg2ok->?
  ?         ?         ?
  ?         ?         ?
  V

Above you wouldn't send the second message until
the client finishes processing the first message.
Another method more "asyncish" would be:

TIME   Client X  xmlBlaster
-----  --------  ----------
  ?         ?         ?
  ?         ?<--msg 1-+
  ?       proc1       ?
  ?         ?<--msg 2-+
  ?         +-msg1ok->?
  ?         ?<--msg 3-+
  ?       proc2       ?
  ?         ?<--msg 4-+
  ?         +-msg2ok->?
  ?         ?         ?
  ?         ?         ?
  V

Using the second scheme the Client has a second msg
to process immedeately upon finishing his first message,
without waiting for a message to get to xmlBlaster
and returning.

The system we use, fills the socket until it says a
write would block.  And then adds more to it as soon
as there is room in the buffer.  In this way the
client constantly has msgs to process with out waiting
for network responses.

This is a major drawback to RPC systems, here another
diagram:

TIME   Client X  xmlBlaster
-----  --------  ----------
  ?         ?         ?
  ?         ?<--msg 1-+
  ?       proc1      NOP!
  ?         +-msg1ok->?
  ?        NOP!       ?
  ?         ?<--msg 2-+
  ?       proc2      NOP!
  ?         +-msg2ok->?
  ?        NOP!       ?
  ?         ?         ?
  V

The NOP! stands for wait and do Nothing!  Typical of RPC,
send-of a call and wait for the answer (NOP).


Could it be that network latency (round trip time) is
holding back your system?

Jerry Westrick