IC84433: ON LINUX PLATFORMS, DB2 FCM THREADS (DB2FMCS AND DB2FCMR) MAY HANG IN SELECT() SYSTEM CALL

DB2 Version 10.1 Fix Pack 1 for Linux, UNIX, and Windows
DB2 Version 10.1 Fix Pack 2 for Linux, UNIX, and Windows

APAR status

• Closed as program error.

Error description

• On Linux Platforms, DB2 FCM threads (db2fmcs and db2fcmr) may
  hang in select() system call due to possibly reaching file
  descriptor limit . The symptom would be hard to confirm via a
  stack trace of the FCM threads since the stack generation tools
  (db2pd -stack, pstack, gstack, gcore) will all clear up the
  hang.
  
  With this APAR db2fcm (s and r)  threads will have the ability
  to use epoll() instead of select() since epoll() does not have
  the file descriptor limit that select() has.  This change will
  not be by default but instead enabled via a registry variable -
  DB2_FCM_FDPOLL.  The default for this registry variable will be
  FALSE on Linux.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * DB2 Users on Linux                                           *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * upgrade to DB2 Version 10.1.1 or higher                      *
  ****************************************************************
  

Problem conclusion

• Problem was first fixed in DB2 Version 10 Fix Pack 1
  

Temporary fix

Comments

APAR Information

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

  IC81639

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

Fix information

• Fixed component name

  DB2 FOR LUW

• Fixed component ID

  DB2FORLUW

Applicable component levels

• RA10 PSN

     UP