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Date: Wed, 2 Jun 2010 09:35:56 -0700
Message-ID: <AANLkTinFVERTofyhVlH6XnSru_kmXERrozNpnSlPzu6S@mail.gmail.com>
Subject: Re: Nodes dropping out of cluster due to GC
From: Ryan King <ryan@twitter.com>
To: user@cassandra.apache.org
Cc: cassandra-user@incubator.apache.org
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Why run with so few nodes?

-ryan

On Tue, Jun 1, 2010 at 4:20 PM, Eric Halpern <eric@dnagamesinc.com> wrote:
>
> Hello,
>
> We're running a 4 node cluster on beefy EC2 virtual instances (8 core, 32
> GB) using EBS storage with 8 GB of heap allocated to the JVM.
>
> Every couple of hours, each of the nodes does a concurrent mark/sweep tha=
t
> takes around 30 seconds to complete. =A0During that GC, the node temporar=
ily
> drops out of the cluster, usually for about 15 seconds.
>
> The frequency of the concurrent mark sweeps seems reasonable, but the fac=
t
> that the node drops out of the cluster temporarily is a major problem sin=
ce
> this has significant impact on the performance and stability of our servi=
ce.
>
> Has anyone experienced this sort of problem? =A0It would be great to hear=
 from
> anyone who has had experience with this sort of issue and/or suggestions =
for
> how to deal with it.
>
> Thanks, Eric
> --
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