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From "" <>
Subject R: Re: R: Re: Ring up but read fails ...
Date Sun, 23 Jan 2011 18:25:55 GMT
> Reconnect and try again?
Sorry what do you mean by "Reconnect and try again?" -- You mean to shut down the old pool
and create a new pool of connections?I don't have the possibility to handle the single connection
using Pelops ...
>From Dominic Williams Blog 
"To work with a Cassandra cluster, you need to start off by defining a  connection pool. This
is typically done once in the startup code of your  application"[...]
"One of the key design decisions that at the time of writing  distinguishes Pelops, is that
the data processing code written by  developers does not involve connection pooling or management.
Instead,  classes like Mutator and Selector borrow  connections to Cassandra from a Pelops
pool for just the periods that  they need to read and write to the underlying Thrift API.
This has two  advantages.

Firstly, obviously, code becomes cleaner and developers are freed  from connection management
concerns. But also more subtly this enables  the Pelops library to completely manage connection
pooling itself, and  for example keep track of how many outstanding operations are currently
 running against each cluster node.

This for example, enables Pelops to perform more effective client  load balancing by ensuring
that new operations are performed against the  node to which it currently has the least outstanding
operations  running. Because of this architectural choice, it will even be possible  to offer
strategies in the future where for example nodes are actually  queried to determine their

-- - Carlo -

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