[ http://issues.apache.org/jira/browse/DERBY-465?page=comments#action_12316146 ]
Mike Matrigali commented on DERBY-465: -------------------------------------- It is very interesting that the other embedded db's don't seem to need indexing, again without seeing the ddl used for those db's it is hard to tell if somehow they may be automatically building an index. Is the natural key of the table the 1st column in your table? Are the results the same for the other db's if you make it the last column? For your pointbase tests what value do you have for the pointbase log.forcewrite parameter. Here is their writeup about the danger of not forcing log writes: log.forcewrite false When log.forcewrite is false, a physical write to the log file on the disk system will NOT be forced after each commit. It is left to the operating system to flush the buffer onto the disk as per the operating system's schedule. If there is an abnormal termination of the program, there is a possibility that some committed transactions will be lost. In some cases the database may get corrupted. However, a forced write to the log file on the disk WILL occur when the database is closed. With log.forcewrite set to true, whenever there is hardware failure/system reset, the last commit to the log file will be written before the failure. When log.forcewrite is true, every time a commit is made (by manually committing or auto commit = true), a physical write to the log file on the disk system will be FORCED. My interpretation of this is that by default pointbase does not correctly support crash recovery, and probably should be marked so in your write up. > Embedded Derby-PointBase comparison > ----------------------------------- > > Key: DERBY-465 > URL: http://issues.apache.org/jira/browse/DERBY-465 > Project: Derby > Type: Wish > Components: Test > Versions: 10.0.2.1, 10.0.2.0 > Environment: Windows Server 2003, 4 processors, summary CPU 3.00 Ghz, RAM 1 > Gb > Reporter: Peter Kovgan > Attachments: Benchmarks_info_independent.doc, derby-optimization.doc > > I have tested 4 major embedded DB. > I have found that major disadvantage of Derby is > 1)low insert speed and > 2)significant performance degradation in select, update, delete operation > speed starting from some table size. > PointBase in comparison has not such degradation. > It will be better if you improve your product. > Good luck and thank you. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
