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From: Jonathan Ellis <jbellis@gmail.com>
Date: Sat, 20 Feb 2010 10:39:09 -0500
Message-ID: <e06563881002200739w1b0019a0p61bbc92896aa90ff@mail.gmail.com>
Subject: Re: cassandra freezes
To: cassandra-user@incubator.apache.org
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haproxy should be fine.

normal GCs aren't a problem, you don't need to worry about that.  what
is a problem is when you shove more requests into cassandra than it
can handle, so it tries to GC to get enough memory to handle that,
then you shove even more requests, so it GC's again, and it spirals
out of control and "freezes."

https://issues.apache.org/jira/browse/CASSANDRA-685 will address this
by not allowing more requests than it can handle.

On Sat, Feb 20, 2010 at 10:22 AM, Simon Smith <simongsmith@gmail.com> wrote=
:
> I'm still in the experimentation stage so perhaps forgive this hypothetic=
al
> question/idea.=A0 I am planning to load balance by putting haproxy in fro=
nt of
> the cassandra cluster.=A0 First of all, is that a bad idea?
>
> Secondly, if I have high enough replication and # of nodes, is it possibl=
e
> and a good idea to proactively cause GCing to happen?=A0 (I.e. take a nod=
e out
> of the haproxy LB pool, somehow cause it to gc, and then put the node bac=
k
> in... repeat at intervals for each node?)
>
> Simon Smith
>