It definitely sounds like there are resources that you're accumulating and not letting go. Also, it could be an operating system issue where you're exhausting the number of sockets available. Other things to try:<div>
<br></div><div>find out how many sockets are open and what state they're in: netstat -a</div><div>attach visual vm and do a heap dump and see if you can spot an overabundance of any resources: <a href="http://visualvm.java.net/">http://visualvm.java.net/</a></div>
<div>post the relevant code on this list and someone here might spot something interesting</div><div><br></div><div>oh, also, if you're using an execution handler with a memory aware thread pool executor (or ordered memory aware one), and you're running out of threads or memory, the execution handler will pause the netty IO thread, which will slow things down some.</div>
<div><br></div><div>cheers,</div><div>j.<br><br><div class="gmail_quote">On Thu, Oct 20, 2011 at 6:55 PM, philmes <span dir="ltr"><<a href="mailto:phil@digitalcontortions.net">phil@digitalcontortions.net</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">That's one of the things I've checked. I'd expect GC pauses to be temporary,<br>
but a quick check with a profiler shows memory usage to be stable and<br>
negligible GC occurring anyway.<br>
<br>
thanks,<br>
<br>
Phil.<br>
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