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Date: Tue, 7 Apr 2009 18:12:30 -0700 (PDT)
From: Andrew Purtell <apurtell@apache.org>
Reply-To: apurtell@apache.org
Subject: Re: ZK rethink?
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I see this kind of stuff:

2009-04-07 17:58:13,344 - WARN  [NIOServerCxn.Factory:2181:NIOServerCnxn@417] - Exception
causing close of session 0x2208296c38e0000 due to
java.io.IOException: Read error

and bye bye HRS ephemeral znodes, which triggers
(currently) HBASE-1314. 

This I think is ZOOKEEPER-344

    https://issues.apache.org/jira/browse/ZOOKEEPER-344

  - Andy


> From: Ryan Rawson
> Subject: Re: ZK rethink?
> Date: Tuesday, April 7, 2009, 1:53 PM
>
> Thanks for the input Joey, and may I be the first to say
> "holy shit".
> 
> The reason their approach works is because the C API spins
> off OS threads that exist outside the domain of the Java VM,
> which means those threads never get paused for GC processing.
> 
> With that kind of input, we might want to consider doing
> what he did.  Maybe you can donate a bit of code?
> 
> Thanks!
> -ryan
> 
> On Tue, Apr 7, 2009 at 1:49 PM, Nitay
[...]
> > I don't quite understand why the C API with JNI
> > fixes the problem. Did that substantially reduce your
> > tiny, short lived objects to the point where the
> > GC wasn't starving the ZooKeeper IO threads anymore?
> >
> > Perhaps my initial 10 second value was not enough.
> > Andrew, can you try 30 or 60 seconds as a test on your
> > cluster to see if that calms things down?
[...]