[rabbitmq-discuss] Schedule Messages

Fri Oct 1 15:21:18 BST 2010

Sorry to hijack the discussion here, but I'm ++1 on a head-style query of messages in a queue. I can think of several places right off where I could use this.

And I would be careful lumping all AMQP applications into a single bucket when it comes to message size. I would not write an application that interrogated the properties/headers of my batch file processor because it's sending zip files as message bodies but I would if I could get just the props/headers without the body. 

I also have applications that send a key value as the message body; maybe a few bytes in size. It just depends.

jb

On Oct 1, 2010, at 8:46 AM, David Wragg wrote:

> Matthew Sackman <matthew at rabbitmq.com> writes:
>> On Fri, Oct 01, 2010 at 01:45:46PM +0100, Michael Bridgen wrote:
>>> In the case of plugins, using a direct connection is effectively the
>>> same thing, by the way.
>> 
>> No it's not. The msg may be fully on disk and not in RAM, at which point
>> you have to issue a disk read regardless of whether the client is
>> embedded or not.
>> 
>> Furthermore, we do not store the message headers separately from the msg
>> body. Thus the only thing you're saving by getting one, not the other,
>> is network transfer. And given the average message body size, ethernet
>> frame size and the fact that we turn nagel off, I'm not convinced in the
>> average case you'd actually save anything at all, but I could be missing
>> something.
> 
> We'd get the network traffic saving immediately.  And if worthwhile,
> later on we could store message bodies separately, above a certain size
> threshold.  At the moment there is no motivation to consider doing that,
> because AMQP always transmits the properties and body together.
> 
> And I doubt there is a meaningful notion of the average message body
> size.  Different AMQP applications have different characteristics.
> 
> -- 
> David Wragg
> Staff Engineer, RabbitMQ
> SpringSource, a division of VMware
> _______________________________________________
> rabbitmq-discuss mailing list
> rabbitmq-discuss at lists.rabbitmq.com
> https://lists.rabbitmq.com/cgi-bin/mailman/listinfo/rabbitmq-discuss

Thanks!

J. Brisbin
http://jbrisbin.com/

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.rabbitmq.com/pipermail/rabbitmq-discuss/attachments/20101001/e45b971f/attachment-0001.htm>