incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Héctor Izquierdo Seliva <>
Subject Re: Disable Swap? batch_mutate failed: out of sequence response
Date Wed, 06 Apr 2011 07:18:57 GMT
I took a look at vmstats, and there was no swap. Also, our monitoring
tools showed no swap being used at all. It's running with mlockall and
all that. 8GB heap on a 16GB machine

El mar, 05-04-2011 a las 21:24 +0200, Peter Schuller escribió:
> > Would you recommend to disable system swap as a rule?   I'm running on Debian 64bit
and am seeing light swapping:
> I'm not Jonathan, but *yes*. I would go so far as to say that
> disabling swap is a good rule of thumb for *most* production systems
> that serve latency sensitive traffic. For a machine dedicated to
> Cassandra, you definitely want to disable swap.
> There's just nothing to be gained really, but lots to loose. There is
> nothing that you *want* swapped out. All the memory you use needs to
> be in memory. You don't want the heap swapped out, you don't want the
> off-heap jvm malloc stuff swapped out, you don't want stacks swapped
> out,etc. As soon as you start swapping you very quickly run into poor
> and unreliable performance. Particularly during GC.

View raw message