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Date: Tue, 14 Dec 2010 07:52:58 -0600
Message-ID: <AANLkTiknTbj2AbhPSfhWx1d5ihk75LWuz94nSn0f_9Y1@mail.gmail.com>
Subject: Re: Running multiple instances on a single server --micrandra ??
From: Gary Dusbabek <gdusbabek@gmail.com>
To: user@cassandra.apache.org
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On Tue, Dec 7, 2010 at 20:25, Edward Capriolo <edlinuxguru@gmail.com> wrote:
> I am quite ready to be stoned for this thread but I have been thinking
> about this for a while and I just wanted to bounce these ideas of some
> guru's.
>
> ...
>
> The upsides ?
> 1) Since disk/instance failure only degrades the overall performance
> 1/6th (RAID0 you lost the entire node) (RAID5 still takes a hit when
> down a disk)
> 2) Moves and joins have less work to do
> 3) Can scale up a single node by adding a single disk to an existing
> system (assuming the ram and cpu is light)
> 4) OPP would be "easier" to balance out hot spots (maybe not on this
> one in not an OPP)
>

Sorry for chiming in so late, but another benefit is that it amortizes
stop-the-world garbage collection across 6 jvms.

> What does everyone thing? Does it ever make sense to run this way?
>

I think it would be a great way of utilizing CPU and memory, assuming
you can come up with the IO bandwidth.

Gary.