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From David Strauss <>
Subject Re: Replacing Redis
Date Mon, 21 Feb 2011 02:08:07 GMT
On Sun, 2011-02-20 at 09:04 -0500, Benson Margulies wrote:
> There are two parts to the data footprint, one growing more rapidly
> than the other. The faster growing part has a natural 'redis-friendly'
> data model (keys map to values); but it would map to EHCache as well.

If you're coming into the non-relational world with the perspective that
the main consideration is your "data model," you're approaching the
problem from the wrong direction. The non-relational world isn't about
BCNF or foreign keys. Storing and retrieving individual items is the
easy part; we need to understand how you intend to *use* the data to
help you understand if Cassandra is a good fit.

      * How do you add new data?
      * Other than accessing individual items by their primary key (or
        equivalent), how do you read it?
      * What needs to be real-time? Asynchronous?
      * What correctness or consistency constraints can you relax?
      * What availability needs do you have?
      * What programming languages are you working in?

> However, the initial redis/jredis implementation used redis, rather
> than local ordinary JVM objects, for the slower growing part. The
> lpush/ltrim usage was in here.

It's not clear just from your use of lpush/ltrim what you're doing. Some
uses can map to Cassandra's APIs with some creative reinterpretation;
others can't.

David Strauss
   | +1 512 577 5827 [mobile]

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