Getting Help

For non-production issues, you can get help from these resources:

• report the issue to the mdbm-users mailing list

• Create a Bug ticket

  1. Provide configuration information:

     • Highly recommended: Attach output from mdbm_environment.sh. This script gathers environment and MDBM information. This script has been tested only on RHEL.

     • Alternatively, manually provide:

       • Platform information, including version: RHEL4/5/6, FreeBSD4/6

         • uname -a
         • cat /etc/redhat-release for RHEL

       • Output from:

         • mdbm_stat -H mdbm-file
         • mdbm_check mdbm-file

       • Provide mdbm_stat output for your mdbm (use an attachment, and do not remove any information)

  2. In your ticket’s description provide application information:

     • If you have a crash, provide a gdb backtrace from backtrace full

     • What kind of MDBM locking are you using?

       • none
       • exclusive (database-level locking)
       • partition, sometimes mistakenly called “page” locking
       • shared, sometimes called “read-write” locking, and new in MDBM v3

     • Do multiple processes have your MDBM open? If so, have you tried stopping all processes and starting them to see if the problem goes away?

     • Is your application the only process/thread that has your MDBM open?

       • If you have a multi-threaded application, only 1 thread may use an MDBM handle at time (i.e., a single operation context such as lock, fetch, unlock)

     • Is the mdbm_replace utility being used by your application? If it’s being used, and you are experiencing MDBM corruption, does the corruption result soon after an MDBM is replaced?

     • What MDBM operation(s) were you doing when the fault occurred? The most common ones are:

       Fetch	Store	Delete	First	Next
       mdbm_fetch	mdbm_store	mdbm_delete	mdbm_first	mdbm_next
       mdbm_fetch_buf	mdbm_store_r	mdbm_delete_r	mdbm_first_r	mdbm_next_r
       mdbm_fetch_r	mdbm_store_str	mdbm_delete_str	mdbm_firstkey	mdbm_nextkey
       mdbm_fetch_dup_r			mdbm_firstkey_r	mdbm_nextkey_r
       mdbm_fetch_str

       • Provide your source for the failing MDBM operation, and its parameters
       • Provide your mdbm_open source and corresponding parameter values

     • Do you have a copy of your MDBM available for inspection?

     • Is your problem reproducible? If so, how easy/hard is it to reproduce?

     • If problem resulted in a core dump, can you provide the stack trace?