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Is there anyway to synchronise client using cassandra built in functions?

I need to perform some operations and those operations need to be synchronized with all other clients (mutual exclusion).

In RDBMS I can lock entire table or prepare special table for synchronization purposes and use SELECT ... FOR UPDATE on it.

Can I achive this with Cassandra without any third party apps? If not what's the best way to do that? Preferable languages are Java and Python.

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Its not possible to lock an entire (or a subset of a) column familiy without third party libraries like Apache ZooKeeper.

I would probably start looking at Domic Williams cages before start rolling my own distributed locking mechanism

于 2011-01-17T21:17:12.633 回答
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If you are updating one row in a column family, it is atomic. But it won't work like select for update. You should probably revisit your data model with more denormalization in mind, so that you won't need to worry about synchronization.

于 2011-01-25T21:34:16.963 回答
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Because C* provides row level atomicity why not use Lamport's Bakery Algorithm. I found an incomplete page on C* wiki too.

https://github.com/jakedouglas/cassandra_lock

于 2012-05-19T13:53:21.483 回答
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I was also looking way to make syncronization with cassandra, but as far as I know it does not provide mechanisms to implement mutexes.

However, memcached has atomic cas (check and set) operation, which can be used to implement mutex. It has also python and java clients.

So you could use memcached to implement mutexes for syncronization and does read/write data with quorum consistency level in cassandra to make sure that latest write is always returned on when reading.

Has anyone experience about implementing mutex with memcached?

于 2011-03-19T21:01:30.910 回答