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From: Ryan King <ryan@twitter.com>
Date: Wed, 22 Jun 2011 10:09:00 -0700
Message-ID: <BANLkTi=E2mRxG62AXP9yDPawm0TC8BczAg@mail.gmail.com>
Subject: Re: simple question about merged SSTable sizes
To: user@cassandra.apache.org
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On Wed, Jun 22, 2011 at 10:00 AM, Jonathan Colby
<jonathan.colby@gmail.com> wrote:
> Thanks for the explanation. =C2=A0I'm still a bit "skeptical".
>
> So if you really needed to control the maximum size of compacted SSTables=
, =C2=A0you need to delete data at such a rate that the new files created b=
y compaction are less than or equal to the sum of the segments being merged=
.
>
> Is anyone else running into really large compacted SSTables that gave you=
 trouble with hard disk capacity? =C2=A0How did you deal with it?
>
> We have 1 TB disks in our nodes, but keeping in mind we need to have at l=
east 50% for the worst case compaction scenario I'm still a bit worried tha=
t one day we're going to hit a dead end.

You should stripe those disks together with RAID-0.

-ryan