DB2 - Problem description
Problem IC94869 | Status: Closed |
COORDINATOR AGENT MAY HANG WITH PENDING REMOTE REQUEST STATUS DUE TO DISCARDED BUFFER. | |
product: | |
DB2 FOR LUW / DB2FORLUW / A50 - DB2 | |
Problem description: | |
The FCM buffer discarded message can be seen in db2diag.log on a remote partition. 2013-08-05-01.09.07.477149+480 I16501733A701 LEVEL: Error PID : 2294174 TID : 1543 PROC : db2sysc 10 INSTANCE: db2inst1 NODE : 010 EDUID : 1543 EDUNAME: db2fcmr 10 FUNCTION: DB2 UDB, fast comm manager, sqkfFastCommManager::RouteInboundBuffer, probe:30 DATA #1 : <preformatted> rc = 0x0; buffer addr: 7800000a3a39080 buffer info: channel ID=478015836, sender node=0, conduit ID=0, sequenceNo=4294967295, sessionId=0, priority=0, msgFlags=0x30009, msgType=1 app_hdl=0-18506, app_stamp=594176, sourceNode=0, idtype=1, idflags=0, bdsCounter=28, nestedCounter=0 (BDS) subtaskId=33, sendNode=0, intFlags=0x0, bdsFlags=0x2 (BQS) counter=33, node=0 DB2 has an internal unique counter called app_stamp based off epoch time for each incarnation of an app-handle. But due to the way DB2 calculates this unique number, it can wrap. Because the unique identifier wraps, it caused a problem in the logic of our code that ultimately lead to a buffer being discarded, and an application being hung. Note : - On DB2 Version 9.7 or higher, EDUNAME is db2pdbc and the FUNCTION is sqkfFastCommManager::DeliverBufferToTargetChannel, probe:30 - This issue only applies to the DB2ᄅ partitioned database environment. - This issue also impacts pureScale instance. | |
Problem Summary: | |
The FCM buffer discarded message can be seen in db2diag.log on a remote partition. 2013-08-05-01.09.07.477149+480 I16501733A701 LEVEL: Error PID : 2294174 TID : 1543 PROC : db2sysc 10 INSTANCE: db2inst1 NODE : 010 EDUID : 1543 EDUNAME: db2fcmr 10 FUNCTION: DB2 UDB, fast comm manager, sqkfFastCommManager::RouteInboundBuffer, probe:30 DATA #1 : <preformatted> rc = 0x0; buffer addr: 7800000a3a39080 buffer info: channel ID=478015836, sender node=0, conduit ID=0, sequenceNo=4294967295, sessionId=0, priority=0, msgFlags=0x30009, msgType=1 app_hdl=0-18506, app_stamp=594176, sourceNode=0, idtype=1, idflags=0, bdsCounter=28, nestedCounter=0 (BDS) subtaskId=33, sendNode=0, intFlags=0x0, bdsFlags=0x2 (BQS) counter=33, node=0 DB2 has an internal unique counter called app_stamp based off epoch time for each incarnation of an app-handle. But due to the way DB2 calculates this unique number, it can wrap. Because the unique identifier wraps, it caused a problem in the logic of our code that ultimately lead to a buffer being discarded, and an application being hung. Note : - On DB2 Version 9.7 or higher, EDUNAME is db2pdbc and the FUNCTION is sqkfFastCommManager::DeliverBufferToTargetChannel, probe:30 - This issue only applies to the DB2© partitioned database environment. - This issue also impacts pureScale instance. | |
Local Fix: | |
Recycle the db2 instance. | |
available fix packs: | |
DB2 Version 10.5 Fix Pack 3 for Linux, UNIX, and Windows | |
Solution | |
First fixed in DB2 Version 10.5 Fix Pack 3. | |
Workaround | |
Recycle the db2 instance. | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 13.08.2013 06.05.2014 06.05.2014 |
Problem solved at the following versions (IBM BugInfos) | |
Problem solved according to the fixlist(s) of the following version(s) | |
10.5.0.3 | |
10.5.0.3 |