as long as there is at least one server up talking to the database, the hourly quartz jobs run and compress / purge the last hour of measurement data. when all servers are down, however, these jobs do not run. then, when one of the servers is started back up, it could have a very large backlog of data to process. to help smooth this out, the compression / purge routines should break up the work to be done in smaller chunks. the chunks should be equivalent to the size of the job that needs to be done (1hr chunks for _1H table, 6hr chunks for _6H table, etc).
rev4933 - perf enhancement for measurement purging (mazz)
rev4967 - chunk up the measurement compression by intervals;
rev4971 - pass correct interval parameter to purge methods;
rev4972 - always purge backwards in time from 'purgeBefore' until the oldest timestamp available in that table;
rev4975 - need to use greater-or-equal to catch the timestamps directly on the hour, which is guaranteed because we round is off timestamps for compression purposes;
rev4977 - pass correct interval parameter to purge methods;
rev4983 - make transaction timeouts for purge / compress chunk methods to be 20 mins; catch throwable from the calling content so that data purge / compress always attempts to execute all chunks;
rev4984 - increase transaction timeouts for purge / compress chunk methods to 60 mins, which is necessary when servers are coming online and flooding with backlogged agent data;
re-opening because these fixes aren't in trunk yet, only in the perf branch.
rev5081 - chunk the work for purging and compression; always purge backwards in time from 'purgeBefore' until the oldest timestamp available in that table; use greater-or-equal-to comparison to catch the timestamps directly on the hour, which is always the case because timestamps are rounded off during compression; catch throwable from the calling context so that data purge / compression always attempts to execute all chunks each time its run; modify transaction timeout to 60 minutes, which is necessary when servers are coming online and flooding the server with backlogged data;
QA Closing - Code change
This bug was previously known as http://jira.rhq-project.org/browse/RHQ-2372
*** Bug 534571 has been marked as a duplicate of this bug. ***
Mass move to component = Monitoring