Hey All,
I am new to C* community. We are planning to use Datastax C* (pre 2.1) in production. We heavily use counters and it is mostly what we do apart from storing the few months raw logs in C*. I have gone through the excellent Sylvain Lesbresne ppt <http://www.datastax.com/wp-content/uploads/2011/07/cassandra_sf_counters.pdf>and the design doc<https://issues.apache.org/jira/secure/attachment/12459754/Partitionedcountersdesigndoc.pdf> for the pre 2.1 counter implementation in detail. Unfortunately the video is not available. *Questions:* 1. I know from https://issues.apache.org/jira/browse/CASSANDRA-6504 that Counters design has changed in 2.1 but not able to get hold of the deign doc. Can someone plz share the design docs? Also according to the 6504 issue and C* codebase CounterMutation.apply(), C* 2.1 has introduced locks that were not existent before. How does it impact the write performance of counter as compared to pre 2.1 no lock partition counter implementation? 2. What were the major concerns (other than idempotency and overcount due to timeout exceptions) in the pre 2.1 counters architecture that led to a rewrite of counters implementation? Thanks for the help. --Unilocal
