Hi,

I'm testing the qpid distribution using the pub-sub examples that come as
part of the python distribution and have certain doubts

1. Is ttl handled only by brokers ? At which points can a message be
dropped? Is there a way to track how many such messages where dropped? I'm
trying to look at this feature as a way to reduce bandwidth euqirements for
slow clients for data which is useless after max n secs. Is this the way
this feature is supposed to be used?

2. The original publisher sample sets the message destination to be the
amq.topic. I tried modifying the publisher to send the message to the
amq.fanout exchange. (session.message_transfer(destination="amq.fanout",
message=....).

But my client which subscribes from the amq.topic exchange does not get the
message. Why is this so? My understanding was that fanout would send a copy
to ALL queues in the system?

3. How expensive are multiple subscriptions using amq.headers exchange? I'm
trying to evaluate a use case where there would be hundreds (600-800) of
clients per broker, with each having multiple subscriptions for multiple
data items (100 or so). I'm not sure if its better to create a single HUGE
subscription for all the data or multiple ones. Or is it better to simply do
all the filtering at the client end? (WAN links so amount of data
transffered is a sensitive issue). Any guidance would be really appreciated
here.

4. What is the preferred way to measure latency / throughput at each point
of conduct ? Does qpid have any special headers that can track this
automatically or is should this be done by the app itself?

Thanks in Advance
gs

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