Re: Latency during send

On Thursday 1 September 2005 19.47, Rebecca Witmer wrote:

> consistent with the estimates I read that indicate that OpenJMS can send
> hundreds of messages per second.

Can't help you here other than to say that timing is dependent on a lot of 
factors: load, backing store characteristics, concurrency between processes 
etcetera. However...

> At this point we're considering restructuring the app to send all the data
> it needs to send in one large conglomerate message rather than 24 or so
> small ones. It seems that that might work faster. Does anyone agree? Does
> anyone have any thoughts as to what can cause intermittent latency that
> worsens over time like that? We've tried to eliminate potential problems in
> the operating environment one at a time but nothing seems to change
> anything.

... here I /do/ have an opinion. Batching the messages can only be done if and 
only if they can be processed as a batch and if they belong to the same 
transaction. Why? Because one use for a message queue is to guarantee 
delivery and transactional acknowledgement of reception. This means that you 
should only process one message consisting of related parts followed by an 
acknowledgement of reception in a single blow. 

That said, if the messages /are/ related in that way, you should note that a 
message is stored in a BLOB. Most of the time these can be very large, but if 
you ask me one should not make them too large because that would probably 
lead to problems in the backing store.

-- 
R.F. Pels,  3e Rompert 118,  5233 AL  's-Hertogenbosch,  The Netherlands
+31736414590       [email protected]       http://home.tiscali.nl/~ruurd



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