I'm new to ActiveMQ and I'm trying to tune a very simple queue setup which I'm relocating from disk to memory-only (VM transport, embedded broker, launched from Spring).
Versions below, but I game for changing them as needed: ActiveMQ core 5.1.0 Spring core 2.5.6 I have about 12 queues, each has a single consumer and a handful of transient producers (max of 6). Everything is in one 64-bit JVM. Some of the messages are quite large (several MB) so I want to have a tight reign on those queues, allowing only perhaps 8-9 messages in memory in total at any one time. 1. I've been all over the ActiveMQ site and the draft of the forthcoming book by Synder, Davies and Bosnac, but I can't find a comprehensive config reference for ActiveMQ anywhere, and it seems that a number of the config settings are not documented. Am I missing something? Should I buy the TTM reference? 2. Is there a way to control the size of in-memory queues based on the number of messages, rather than the size in megabytes? Since my messages are never serialized, AMQ has no way to know how big they are. I found one (and only one) reference to a parameter called minimumMessageSize which - name notwithstanding - seems to be used as a proxy for the size of an unserialized message when doing storage management calculations (link below). http://activemq.apache.org/per-destination-policies.html I looked at constantPendingMessageLimitStrategy but it seems to me that this throws messages away, rather than blocking the producer, which is what I want to do when the queue is full. Is the canonical thing to do here to set minimumMessageSize to (e.g.) 1MB and then use MB memory limits as a proxy for message count in the <amq:memoryUsage> tags? 3. It seems to me that if I control memory size using the queue, then I should set the pre-fetch size to 0 or 1 to prevent prefetch from holding additional messages - is this correct, or do prefetched messages also remain in the queue? 4. Is there a way to completely control memory usage with only the prefetch settings? Cheers Dave -- View this message in context: http://old.nabble.com/Controlling-VM-transport-queu-size-by-count--tp27218974p27218974.html Sent from the ActiveMQ - User mailing list archive at Nabble.com.
