|
Problem IT07002
|
Status: Closed |
CDRSPOOL4ALT THREAD CAN DEADLOCK WITH CDRGFAN ON CDR_GC LOCK, BLOCKING ALTER TABLE AS WELL AS WHOLE ER |
| product: |
INFORMIX SERVER / 5725A3900 / C10 - IDS 12.10 |
| Problem description: |
An ALTER TABLE on a replicated table internally would create a
CDRSpool4Alt thread for advancing the ER replay position to the
position of the current transaction. That thread would spool
the send queue and/or sit waiting on the replay position to
advance - all while the ALTER TABLE holds the CDR_GC lock.
ALTER session:
Stack for thread: 4444659 sqlexec
base: 0x0000000177034000
len: 135168
pc: 0x000000010122fb70
tos: 0x00000001770517f1
state: join wait
vp: 21
yield_processor_mvp
mt_join
cdrInvokeForceSpool4AlterMode
dac_altmode_on
SetCDRAltMode << has gcLock()'ed the GC (CDR_GC)
cdrDDLSetAltMode
cdrDDLAlterTablePreDDL
cdrPreDDLCallBack
ddalter
aud_ddalter
excommand
sq_execute
sqmain
listen_verify
Stack for thread: 4446885 CDRSpool4Alt
base: 0x000000016620d000
len: 69632
pc: 0x000000010122fb70
tos: 0x000000016621d2f1
state: sleeping
vp: 22
yield_processor_mvp
cdrSpoolSendQ4AlterMode
th_init_initgls
startup
Now one of the threads involved in getting the replay position
moved, the CDRGfan thread, can end up in the following activity
- having to wait on that very CDR_GC lock:
Stack for thread: 145 CDRGfan
base: 0x0000000112872000
len: 69632
pc: 0x000000010122fb70
tos: 0x0000000112880571
state: cond wait
vp: 16
yield_processor_mvp
mt_wait
gcLock
grid_lockGC
gauto_processRemasterRepl
grid_processEROp
grprF_processGridOps
grouperFanOutThread
cdrTrampolineThread
th_init_initgls
startup |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* All users *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Update to IBM Informix Server 12.10 *
**************************************************************** |
| Local Fix: |
|
| Solution |
Problem Fixed In IBM Informix Server 12.10 |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 05.02.2015
16.10.2015
16.10.2015 |
| Problem solved at the following versions (IBM BugInfos) |
12.10.0
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 12.10.xC5
|
 |
| 12.10.xC5.W1
|
|
