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From: Jonathan Ellis <jbellis@gmail.com>
Date: Tue, 3 Apr 2012 17:56:43 -0500
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 <CALdd-zijZgEbtvn-7200M2Tbi++8PqpDkGND=pwnev6hGys5Fw@mail.gmail.com>
Subject: Re: Largest 'sensible' value
To: user@cassandra.apache.org
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We use 2MB chunks for our CFS implementation of HDFS:
http://www.datastax.com/dev/blog/cassandra-file-system-design

On Mon, Apr 2, 2012 at 4:23 AM, Franc Carter <franc.carter@sirca.org.au> wr=
ote:
>
> Hi,
>
> We are in the early stages of thinking about a project that needs to stor=
e
> data that will be accessed by Hadoop. One of the concerns we have is arou=
nd
> the Latency of HDFS as our use case is is not for reading all the data an=
d
> hence we will need custom RecordReaders etc.
>
> I've seen a couple of comments that you shouldn't put large chunks in to =
a
> value - however 'large' is not well defined for the range of people using
> these solutions ;-)
>
> Doe anyone have a rough rule of thumb for how big a single value can be
> before we are outside sanity?
>
> thanks
>
> --
>
> Franc Carter | Systems architect | Sirca Ltd
>
> franc.carter@sirca.org.au=A0|=A0www.sirca.org.au
>
> Tel:=A0+61 2 9236 9118
>
> Level 9, 80 Clarence St, Sydney=A0NSW 2000
>
> PO Box H58, Australia Square, Sydney NSW 1215
>
>


--=20
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of DataStax, the source for professional Cassandra support
http://www.datastax.com