>>>>> On Sat, 24 Mar 2007 13:35:28 +0100, Kern Sibbald said: > > Hello, > > As you may remember, one of the things I am working on for version 2.1.x is > performance. My most recent work on performance has been to review and > re-write the pruning and purging code. Over the years, this code has been > added to and patched, and there are a number of issues that I want to > address: > > 1. Review the pruning algorithms to improve the SQL. > 2. Pruning during "status dir" > 3. User complaints that it requires two passes to recycle Volumes > > The basic algorithm for recycling volumes is documented in the manual, and it > will remain unchanged. However, I have now re-written the prune/purge code > to do the following things: > > 1. Reduce unnecessary SQL calls to a minimum > 2. When pruning, submit SQL statements that prune up to 1000 jobs > in a single SQL statement rather than 1000 separate SQL statements. > 3. Prune only a single volume if the SD requests pruning rather than > pruning *all* the volumes in the Pool. > 4. After pruning a Volume, explicitly check if it can be marked as Purged. > 5. Ensure that there are not multiple copies of the same code (pruning and > and purging share a lot code, some of which was duplicated). > > The net result is not a huge gain in performance, except in a few exceptional > cases, but the code base is much cleaner, and I believe I have corrected at > least one case where pruning would be performed but Bacula did not detect and > hence mark the Volume purged. > > There are two issues where I would appreciate a bit of user feedback: > > 1. Previous when Bacula needed a new Volume, it would prune *all* volumes > in the current pool. Now it prunes only one at a time, until it finds > one > that has been Purged. This means that less pruning will be done, and > database records will tend to remain longer (possibly much longer). > Although individual volumes can be prunned by command, there is no > command to prune a whole pool.
Re "until it finds one that has been Purged": will it still consider other volumes if the newly-purged tape is not in the drive? E.g. if there are two tapes A and B, both past their Volume Retention times, what will happen if tape A gets purged first but tape B is in the drive? Currently tape B is purged and recycled as well, which I think is the correct behaviour. Similarly, if tape A is in the drive today and gets purged and recycled, what happens if tomorrow tape B is in the drive? Will it be purged and recycled as well? These are cases where it currently prints "Recycled current volume" __Martin ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
