http://www-01.ibm.com/support/docview.wss?uid=swg21903387

https://advisories.secintel.ibm.com/adv_database.php?adv_id=59904

Commands that access db2 database directory like connect to database, create database, list database directory etc. might hang

Technote (troubleshooting)

Problem(Abstract)

Commands that access db2 database directory like connect to database, create database, list database directory etc. might hang with most frequently seen stack as:

*** stack ***

0x090000000A7FBB64 thread_waitlock@glue884 + 0x8C

0x090000000A7FB90C sqloXlatchConflict + 0x1CC

0x090000000A7FB67C sqloXlatchConflict@glue1AC + 0x78

0x090000000D137084 sqleGetDirCacheLatch__Fv + 0x68

0x090000000AA00544 sqlehdir__FP8SQLE_BWA + 0x13C

0x090000000AA643DC

sqleUCconnectDirLookup__FP8sqeAgentP14db2UCconHandle + 0xC0

0x090000000AA823D8

@63@sqljsVerifyAgent__FP8sqeAgentP14db2UCconHandlePb + 0x1F4

0x090000000AA81D78

@63@sqljsInitAgent__FP8sqeAgentP18SQLCC_INITSTRUCT_TP14db2UCconH

andlePbPPc + 0x2F4

0x090000000AA8106C

@63@sqljsDrdaAsInnerDriver__FP18SQLCC_INITSTRUCT_Tb + 0x234

0x090000000AA80B7C sqljsDrdaAsDriver__FP18SQLCC_INITSTRUCT_T +

0xEC

0x090000000A9EA5D8 RunEDU__8sqeAgentFv + 0x2F0

0x090000000A9E7C34 EDUDriver__9sqzEDUObjFv + 0xE4

0x090000000A72A1A0 sqloEDUEntry + 0x250

Other stacks that could also be seen:

*** Stack ***

Timestamp: 2015-05-05-21.00.39.463844

0x09000000000B0C20 open + 0x100

0x09000000000B0500 open64 + 0x40

0x0900000017DA9150 sqloopenp + 0x62C

0x0900000017DD73E4 sqlegopn__FPcP12SQLO_FHANDLEc + 0x98

0x0900000017DD700C sqledogd__FP8SQLE_BWAcT2 + 0x1B0

0x0900000017DD900C read_volume_directory__FP13SQLO_MEM_POOLPcPP24sqle_vol_dir_cache_entry + 0xBC

0x0900000017DD8E60 @32@read_system_directory__FP8SQLE_BWAPP15sqle_decb_cachePP24sqle_vol_dir_cache_entry + 0x334

0x0900000017DD7D98 sqlecdbd + 0x8C

0x0900000012C836E4 sqlecdbd@glue61C + 0x74

0x09000000132E3030 sqlehdir__FP8SQLE_BWA + 0x470

0x0900000017E052FC sqleUCconnectDirLookup__FP8sqeAgentP14db2UCconHandle + 0xC8

0x0900000017E056F4 sqleUCagentConnect + 0x1F4

0x0900000017E042CC sqljsConnectAttach__FP13sqljsDrdaAsCbP14db2UCinterface + 0x10C

0x0900000017E04014 sqljs_ddm_accsec__FP14db2UCinterfaceP13sqljDDMObject + 0x34C

Symptom

Hang detected

Cause

If the dbm cfg parameter dir_cache is set to yes (default), commands that access database directory like create db, list db directory, connect to db might hang indefinitely waiting to acquire sqleDirCacheLatch latch.

This problem exists only in IBM DB2 v9.7FP10

Diagnosing the problem

db2dump containing stacks as mentioned above.

Resolving the problem

Upgrade to IBM DB2 v9.7FP11 or later releases.

On IBM DB2 v9.7FP10, apply APAR fix IT05909.

Workaround:

db2 update dbm cfg using dir_cache no

db2set DB2LDAPCACHE=NO

解决：

打补丁或者升级
Upgrade to IBM DB2 v9.7FP11 or later releases.

On IBM DB2 v9.7FP10, apply APAR fix IT05909.


临时解决，需要将下面的参数设置为NO

db2 update dbm cfg using dir_cache no

db2set DB2LDAPCACHE=NO

[db2inst1@centos65-02 ~]$ db2 get dbm cfg  | grep -i dir_cache

 Directory cache support                     (DIR_CACHE) = YES

[db2inst3@kvm61 ~]$ db2set -all

[i] DB2LDAPCACHE=NO

[i] DB2COMM=tcpip

[i] DB2AUTOSTART=NO

[g] DB2FCMCOMM=TCPIP4

[g] DB2SYSTEM=kvm61

[g] DB2INSTDEF=db2inst3