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From: Alain RODRIGUEZ <arodrime@gmail.com>
Date: Fri, 23 Aug 2013 10:01:44 +0200
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 <CA+VSrLo=3unnfjxnpXDKW7Hh3coFyhOAsqzRmFVENG4LOSuvLg@mail.gmail.com>
Subject: Periodical deletes and compaction strategy
To: user@cassandra.apache.org
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Hi,

I am currently using about 10 CF to store temporal data. Those data are
growing pretty big (hundreds of GB when I actually only need information
from the last month - i.e. about hundreds of MB).

I am going to delete old (and useless) data, I cannot always use TTL since
I have counters too. Yet I know that deletes are a bit tricky in Cassandra,
due to the fact that they are distributed.

I was wondering about the best way to keep high performance and get rid of
tombstones easily.

I was considering 2 ways to do it :

- Major compaction on these 10 CF to force them to always keep fresh data
only and remove tombstones
- LCS to have more chance to get all parts of the row in one SSTable,
allowing tombstones to be removed eventually.

What would be the better option (i.e. what would be the impact of both
solutions) ?
Do you need more information about those CF to answer this question ?

Any insight is welcome, as always.

Alain

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<div dir=3D"ltr"><div>Hi,</div><div><br></div><div>I am currently using abo=
ut 10 CF to store temporal data. Those data are growing pretty big (hundred=
s of GB when I actually only need information from the last month - i.e. ab=
out hundreds of MB).</div>

<div><br></div><div>I am going to delete old (and useless) data, I cannot a=
lways use TTL since I have counters too. Yet I know that deletes are a bit =
tricky in Cassandra, due to the fact that they are distributed.</div><div>

<br></div><div>I was wondering about the best way to keep high performance =
and get rid of tombstones easily.</div><div><br></div><div>I was considerin=
g 2 ways to do it :</div><div><br></div><div>- Major compaction on these 10=
 CF to force them to always keep fresh data only and remove tombstones</div=
>

<div>- LCS to have more chance to get all parts of the row in one SSTable, =
allowing tombstones to be removed eventually.</div><div><br></div><div>What=
 would be the better option (i.e. what would be the impact of both solution=
s) ?</div>

<div>Do you need more information about those CF to answer this question ?<=
/div><div><br></div><div>Any insight is welcome, as always.</div><div><br><=
/div><div>Alain</div></div>

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