[rabbitmq-discuss] consumer get messages from one queue sometimes disorder

[Simon MacMullen]

On 07/05/2013 09:26, Emile Joubert wrote:
> On 06/05/13 11:08, Xie Yunpeng wrote:
>
>> I use 4 publisher sending messages to this queue and 1 consumer to
>> receive the messages.the consumer when connect to the rabbitmq server ,
>
>> i find it receive messages disorder sometimes, just like: first receive
>> messges in current time and then receive messages several hour ago, the
>> interval is not regular.
>
>
> You can find the ordering guarantees here:
> http://www.rabbitmq.com/semantics.html#ordering
> In particular, there is no ordering guarantee if you involve multiple
> publishers.

Well, there's still exactly the same ordering guarantee as there is with 
a single publisher: messages from each publishing channel won't get 
reordered with respect to each other. We just don't guarantee anything 
about ordering between channels. And indeed it's hard to see how we could.

To the OP: either something weird is happening in your publishers 
causing them to buffer messages for hours before sending to RabbitMQ 
(unlikely I guess but I should mention it) or messages are not being 
acknowledged by your consumers and are then being requeued once the 
consumer disconnects. In the latter case all the "late" messages should 
have the "redelivered" flag set.

Cheers, Simon