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Aleksey Yeschenko edited comment on CASSANDRA-9673 at 7/13/15 10:38 AM: ------------------------------------------------------------------------ Yes, I thought I mentioned it offline (and it should really all be in the ticket, either way, so my bad). The mutations will now be stored in a map {{<something, blob>}}. The missing, and, again, unexplained part is that we don't decode the message from {{ByteBuffer}} s into {{Mutation}} s on the receiving side. There is no point in doing so, given that only replay needs the {{Mutation}} objects. was (Author: iamaleksey): Yes, I thought I mentioned it offline (and it should really all be in the ticket, either way, so my bad). The mutations will now be stored in a map {{<something, blob>>}}. The missing, and, again, unexplained part is that we don't decode the message from {{ByteBuffer}}s into {{Mutation}}s on the receiving side. > Improve batchlog write path > --------------------------- > > Key: CASSANDRA-9673 > URL: https://issues.apache.org/jira/browse/CASSANDRA-9673 > Project: Cassandra > Issue Type: Improvement > Reporter: Aleksey Yeschenko > Assignee: Stefania > Fix For: 3.0.0 rc1 > > > Currently we allocate an on-heap {{ByteBuffer}} to serialize the batched > mutations into, before sending it to a distant node, generating unnecessary > garbage (potentially a lot of it). > With materialized views using the batchlog, it would be nice to optimise the > write path: > - introduce a new verb ({{Batch}}) > - introduce a new message ({{BatchMessage}}) that would encapsulate the > mutations, expiration, and creation time (similar to {{HintMessage}} in > CASSANDRA-6230) > - have MS serialize it directly instead of relying on an intermediate buffer > To avoid merely shifting the temp buffer to the receiving side(s) we should > change the structure of the batchlog table to use a list or a map of > individual mutations. -- This message was sent by Atlassian JIRA (v6.3.4#6332)