[ https://issues.apache.org/jira/browse/FLUME-2155?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Hari Shreedharan updated FLUME-2155: ------------------------------------ Attachment: (was: SmartReplay.pdf) > Improve replay time > ------------------- > > Key: FLUME-2155 > URL: https://issues.apache.org/jira/browse/FLUME-2155 > Project: Flume > Issue Type: Bug > Reporter: Hari Shreedharan > Assignee: Hari Shreedharan > Attachments: 100000-110000, 10000-20000, 300000-310000, > 700000-710000, fc-test.patch, SmartReplay.pdf > > > File Channel has scaled so well that people now run channels with sizes in > 100's of millions of events. Turns out, replay can be crazy slow even between > checkpoints at this scale - because of the remove() method in FlumeEventQueue > moving every pointer that follows the one being removed (1 remove causes 99 > million+ moves for a channel of 100 million!). There are several ways of > improving - one being move at the end of replay - sort of like a compaction. > Another is to use the fact that all removes happen from the top of the queue, > so move the first "k" events out to hashset and remove from there - we can > find k using the write id of the last checkpoint and the current one. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira