Oh, I should have mentioned it also caused a rather noticable 35%+ reduction in the time taking to run the tests, going from 19min16sec to 12min24sec for the default java-mms.0-10 profile, which in itself is a good enough reason for me to want it regardless of any actual user benefits ;)
On 8 November 2011 18:00, Robbie Gemmell <[email protected]> wrote: > Hi all, > > I was looking into some sluggish consumer creation performance with > the Java client for a posting on the user list, and eventually > narrowed the issue down to TCP_NODELAY being set false by default, > leading to ExecutionSyncs taking an extraordinary amount of time to > complete. This made every consumer creation take 40-80ms on average, > depending on whether the queue already existed or not (which > influences the operations and number of syncs performed). Enabling > TCP_NODLAY gets this process down to 2-3ms. > > We have previosuly noted poorer performance with the Java broker using > 0-10 than it managed historically with its 0-9 support (which used a > different IO layer on the client until recently), especially when > using transient messages and transactions. Running some noddy tests > sugggests TCP_NODELAY (which is enabled on the broker by default) to > be the root cause of those issues too, because it also caused > performance to increase somewhere between mildly noticable and mouth > open levels depending on what you are doing. > > I understand there may be certain situations where this is slightly > slower and that it could lead to higher bandwidth usage in some cases, > but the effect of enabling it seems generally far too positive not to > do so by default (which is what some other messaging products seem to > do). Is there a strong argument not to? Does anyone know off hand what > the other clients do? > > I plan to change the default for the Java client to true in a day or > two unless talked out of it. > > Robbie > --------------------------------------------------------------------- Apache Qpid - AMQP Messaging Implementation Project: http://qpid.apache.org Use/Interact: mailto:[email protected]
