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Jonathan Ellis commented on CASSANDRA-1123: ------------------------------------------- The CassandraServer class logs timeouts at DEBUG level (see CASSANDRA-3661). But I agree this would be a useful "event" to record. > Allow tracing query details > --------------------------- > > Key: CASSANDRA-1123 > URL: https://issues.apache.org/jira/browse/CASSANDRA-1123 > Project: Cassandra > Issue Type: New Feature > Components: Core > Reporter: Jonathan Ellis > Assignee: Aaron Morton > Fix For: 1.2 > > Attachments: 1123-3.patch.gz > > > In the spirit of CASSANDRA-511, it would be useful to tracing on queries to > see where latency is coming from: how long did row cache lookup take? key > search in the index? merging the data from the sstables? etc. > The main difference vs setting debug logging is that debug logging is too big > of a hammer; by turning on the flood of logging for everyone, you actually > distort the information you're looking for. This would be something you > could set per-query (or more likely per connection). > We don't need to be as sophisticated as the techniques discussed in the > following papers but they are interesting reading: > http://research.google.com/pubs/pub36356.html > http://www.usenix.org/events/osdi04/tech/full_papers/barham/barham_html/ > http://www.usenix.org/event/nsdi07/tech/fonseca.html -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira