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Aleksey Yeschenko commented on CASSANDRA-7359: ---------------------------------------------- Just to be clear - I'm saying that we should close this issue with 'Not a Problem'. And if it does become a proven problem someday, expand the range (and switch to Guava Striped, for consistency with counters). But for now, 'Not a Problem' it. > Optimize locking in PaxosState > ------------------------------ > > Key: CASSANDRA-7359 > URL: https://issues.apache.org/jira/browse/CASSANDRA-7359 > Project: Cassandra > Issue Type: Improvement > Reporter: sankalp kohli > Assignee: Benedict > Priority: Minor > Attachments: 7359.txt > > > In PaxosState, we want to lock on same rows and have created 1024 size array > with java Objects in them to be used for locking. > We should replace these Objects with some Lock so that we can know whether > there is contention trying to acquire a lock for different rows. > We can achieve that by also storing the hash of the row which acquired the > lock. This will tell us if this needs to be improved. > Here is an improvement which I was thinking about. > Say two rows A and B map to the same 1024 bucket which we have. A get the > lock and B has to wait. Here B can check if his hash is different and create > a new object and chain it to the other one. > This looks close to a hashMap with chaining for same key. > The hard part will be removing the entries no longer being used. -- This message was sent by Atlassian JIRA (v6.2#6252)