Robert Mertens wrote:
Hi Florent, I am using the JDBM as a part of the Apache Directory Server. I am switching from OpenLDAP because it's Berkeley did not always shut down properly.
I find that quite difficult to believe. On a properly configured installation we never see corruption or data loss. We've even tested on machines that crashed due to failing DRAMs and the database (containing over 1 terabyte of data) still recovered in under 2 minutes on the subsequent reboot (after replacement of bad memory).
Ever since BerkeleyDB 4.2 came out, we've had no data corruption issues with BerkeleyDB...
The JDBM seems to do the job, but does not seemt to handle emergency shutdowns very well(or is it the Apache Directory Server?). The BTree was corrupted when shutting down the machine it is running on when we, at the same time, performed actions against the Directory Server where we deleted entries. The result was that the Directory Server could not be restarted again without replacing the JDBM. I am waiting for Apache Directory Server team to implement a failover model for such occasions. Best Regards Robert Mertens +46(0)702-793778 ------------------------------------------------------------------------ *From:* Florent Gratta [EMAIL PROTECTED] *Sent:* Wednesday, October 22, 2008 11:20 AM *To:* [email protected] *Subject:* Usage of JDBM : Experience feedbacks Hi All, I am currently Project Lead at Sicap, a Swiss company which designs softwares for mobile operators and the mobile network world in general. We are going to use a BTree library to index entries of csv files. We have identified JDBM library (http://jdbm.sourceforge.net/) and we have seen that you are currently using it in Apache Directory. As there is no more tracker activity on this project and it seems that it is the same thing for support, we would like to know if JDBM is stable: è Have you encountered problems when you use this library in multithreaded mode: Several concurrent inserts at a time? è What is the behaviour of the library when we shut down with emergency? Is it robust? By this way, does BTree file could be corrupted? è Do you encountered performance lack in some cases? è Is there some limitations or lacks: Size of the index chain, cache size etc ... è Etc ... We are very interested on your feedbacks and experiences on JDBM library usage ?
-- -- Howard Chu CTO, Symas Corp. http://www.symas.com Director, Highland Sun http://highlandsun.com/hyc/ Chief Architect, OpenLDAP http://www.openldap.org/project/
