[rabbitmq-discuss] limit number of messages buffered in memory in new persister

[Matthias Radestock]

Tony Garnock-Jones wrote:
> alex chen wrote:
>> For single client with commit on every publish, it can do about 20 msg/sec.
> [...] 
> Part of this can be nagling and general turnaround time. Tx.commit is
> synchronous, unfortunately.

I am pretty sure the root cause is a) fsync, and b) delays coded into 
the persister:

transactional and persistent:
$ sh build/dist/runjava.sh com.rabbitmq.examples.MulticastMain -m 1 -a 
-f persistent -i 2 -z 1
starting consumer #0
starting producer #0
recving rate avg: 9 msg/s
sending rate avg: 9 msg/s

transactional and non-persistent:
$ sh build/dist/runjava.sh com.rabbitmq.examples.MulticastMain -m 1 -a 
-i 2 -z 1
starting consumer #0
starting producer #0
recving rate avg: 2365 msg/s
sending rate avg: 2378 msg/s


Matthew can probably provide a more detailed explanation.


Matthias.