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Josh Elser updated ACCUMULO-3232: --------------------------------- Assignee: (was: Josh Elser) > Improve consumption of WAL header in partial replication case > ------------------------------------------------------------- > > Key: ACCUMULO-3232 > URL: https://issues.apache.org/jira/browse/ACCUMULO-3232 > Project: Accumulo > Issue Type: Improvement > Components: replication > Reporter: Josh Elser > Fix For: 1.7.0 > > > Consider a system that is actively replicating from one instance to another. > Specifically, assume there is one WAL that is currently being replicated to > the destination and the source instance is shutdown. > When the source instance is restarted, it will notice that the WAL has read > through N {{LogFileKey}}/{{LogFileValue}} pairs (from before it was shutdown) > and while proceed past these records to get to the data in the file which it > needs to read. > We have to re-read each of these pairs from the file because the WAL is an > append-only structure, and we can't efficiently seek to some point in the > file, as we wouldn't know how to correlate the byte offset to entries. > As we read the WAL, in addition (or perhaps instead of) tracking the offset > in the WAL, it would be good to track the correlation of N bytes read to M > records consumed which would help us better resume replication. -- This message was sent by Atlassian JIRA (v6.3.4#6332)