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Date: Fri, 1 Oct 2010 23:12:06 +0800
Message-ID: <AANLkTin3rmXkcWmijhnupvmsf5chUZxU4S8cOR=mXFR6@mail.gmail.com>
Subject: Re: [DISCUSSION] High-volume counters in Cassandra
From: Zhu Han <schumi.han@gmail.com>
To: dev@cassandra.apache.org
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> They have however at least one advantage:
>  - your super columns are indexed, you don't have to deserialize them
>    entirely each time.
>

The  size of counter super column is limited to how many replicas propagated
values as the lead replica.  It's size is upper bounded by the number of
replicas.  Even if we support hinted hand off of counters, the size of super
columns just equals to the size of nodes in the cluster, as the worse case.


IMHO, it's not a big deal to de-serialize them entirely, the can fit into
memory very easily. Did I miss anything here?

One advantage of implementing counter as a new CF type:
--you can add some counter specific configuration very easily.

best regards,
hanzhu

To sum up, I can see the following drawbacks to such encoding:
>  - querying SC by names is less efficient.
>  - it takes more disk space (but that's the cheapest resource we have
> isn't it).
>
> I'd say these are fair compromises.
>
> --
> Sylvain
>

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