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Date: Wed, 22 Jun 2011 13:11:15 -0400
Message-ID: <BANLkTin5H99AWNt55QQiABXYTuAc5i5RWw@mail.gmail.com>
Subject: Re: simple question about merged SSTable sizes
From: Eric tamme <etamme@gmail.com>
To: user@cassandra.apache.org
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>> Second, compacting such large files is an IO killer. =A0 =A0What can be =
tuned
>> other than compaction_threshold to help optimize this and prevent the fi=
les
>> from getting too big?
>>
>> Thanks!
>
>

Just a personal implementation note - I make heavy use of column TTL,
so I have very specifically tuned cassandra to having a pretty
constant max disk usage based on my data insertion rate, the TTL, the
memtable flush threshold, and min compaction threshold.  My data
basically lives for 7 days and depending on where it is in the
compaction cycle goes from 130 gigs per node up to 160gigs per node.

If setting TTL is an option for you, It is one way to auto purge data
and keep overall size in check.

-Eric