Posts Tagged ‘CAP’

Cassandra as a communication medium – A service Registry and Discovery tool

Few weeks ago while I was mulling over what kind of service registry/discovery system to use for a scalable application deployment platform, I realized that for mid-size organizations with complex set of services, building one from scratch may be the only option.
I also found out that many AWS/EC2 customers have already been using S3 and [...]

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SimpleDB now allows you to tweak consistency levels

We discussed Brewer’s Theorm a few days ago and how its challenging to obtain Consistency, Availability and Partition tolerance in any distributed system. We also discussed that many of the distributed datastores allow CAP to be tweaked to attain certain operational goals.
Amazon SimpleDB, which was released as an “Eventually Consistent” datastore,  today launched a [...]

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Brewers CAP Theorem on distributed systems

Large distributed systems run into a problem which smaller systems don’t usually have to worry about. “Brewers CAP Theorem” [ Ref 1] [ Ref 2] [ Ref 3]  defines this problem in a very simple way.
It states, that though its desirable to have Consistency, High-Availability and Partition-tolerance in every system, unfortunately no system can [...]

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Cassandra : inverted index

Cassandra is the only NOSQL datastore I’m aware of, which is scalable, distributed, self replicating, eventually consistent, schema-less key-value store running on java which doesn’t have a single point of failure. HBase could also match most of these requirements, but Cassandra is easier to manage due to its tiny footprint.
The one thing Cassandra doesn’t do [...]

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