Re: Physics application using xmlBlaster

[Marcel Ruff <ruff at swand.lake.de>]

> Hi Folks,
>
> I'm evaluating xmlBlaster as a candidate for a message passing system for
> a data acquisition system to be used by a variety of high energy physics
> experiments. The publish/subscribe model fits perfectly this kind of
> application, but it often requires message rates peaks of 100KHz. Size of
> messages vary from a few Bytes up to a MByte. We have successfully used
> commercial publish/subscribe software in the past, but as experiments grow
> larger the licensing price becomes a big problem.
>
> So far, on a few PCs plugged to a switch using 100Mb ethernet I've got
> rates from 50Hz to 200Hz, where each application (xmlBlaster, publisher
> and subscribers) run on a separated node. These rates were measured with
> one publisher and three subscribers at most, sending 100 bytes long
> messages.
>
> Have someone already done this kind of performance tests with xmlBlaster?
> On the web page I see only numbers from a single machine.
>
> Thanks!
Hi Luciano,


does 100KHz mean to send 100000 messages per second?
Well, you are a lucky guy, to have so many data :-)

xmlBlaster can't handle this with today hardware.

Even with raw socket connection this is almost impossible.
Sending only one byte and this 100000 times a second
will occupy on an ethernet with 1500 bytes of package size
approximatly 150MBytes/second.


If you collect for example half a second the messages
on client side and send them in a bunch (we call it burst mode)
could help, but still your requirements are
difficult to solve.

xmlBlaster has the burstmode for callbacks not yet implemented
(it is scheduled - but this can be in years ...).

best regards,

Marcel + Heinrich



--
Marcel Ruff
mailto:ruff at swand.lake.de
http://www.lake.de/home/lake/swand/
http://www.xmlBlaster.org