IZ23718: Application hang due to file locking on DB2 database directory files

APAR status

• Closed as program error.

Error description

• You may encounter hang situations within DB2 environment due to
  locking issue on the local DB2 database directory files.
  
  To update the local database directory a process needs to open
  the corresponding files. Unclosed files may then lead to hangs
  due to OS locking on these files.
  
  Many db2 processes are waiting for latch. They have similar call
  stacks as follow:
  ... _global_lock_common ...
  ... _mutex_lock ...
  ... pthread_mutex_lock ...
  ... sqloxltc_app ...
  ... sqljrGetBestSrvAddr ...
  ... sqljrInternalConnect ...
  ... sqljrLookupAddressAndConnect ...
  
  Meanwhile, a db2 process is trying to open the DB2 database
  directory file (i.e. sqllib/sqldbdir/sqldbdir). Its call stack
  might be silimar to:
  ... open64 ...
  ... sqloopenp ...
  ... sqlegopn ...
  ... sqledogd ...
  ... sqledrcv ...
  ... sqledeop ...
  ... sqleUpdateSysDbDirServerInfo ...
  ... sqlexUpdDbDirEntry ...
  ... sqleUpdateActiveAlternateServer ...
  
  Althought the stack indicates that this is special to
  environments which make use of the DB2 client reroute feature
  every DB2 installation is exposed to this issue.
  

Local fix

• n/a
  

Problem summary

• See Error Description above.
  

Problem conclusion

• First fixed in DB2 Version 8.2 Fix Pack 18
  

Temporary fix

• Upgrade to DB2 Version 8.2 Fix Pack 18
  

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  IZ23729 IZ23730

Fix information

• Fixed component name

  DB2 CEE AIX

• Fixed component ID

  5765F3000

Applicable component levels

• R820 PSN

     UP