The prefetcher reports a bad page header error in
sqlb_verify_page () when reading a temporary page.
The stack trace will show the presence of funcion
sqlbReadAndReleaseBlock() as indicated
below and the page type is always TEMPORARY. While the error is
not harmful and can be ignored,
the fix for this APAR will change the behavior for prefetcher to
ignore when come across this
kind of page instead of throwing error.
Stack trace:
[0] 0x090000000700E0EC pdLog + 0xE8
[1] 0x090000000981C630 sqlbLogReadAttemptFailure
[2] 0x090000000981C3A8 sqlbLogReadAttemptFailure
[3] 0x09000000073A679C sqlb_verify_page
[4] 0x09000000084D1D58 sqlbReadAndReleaseBlock
[5] 0x09000000073DE070 sqlbProcessRange
[6] 0x0900000006E0078C sqlbProcessRange
[7] 0x090000000BBF90C0 sqlbPFPrefetcherEntryPoint
[8] 0x090000000717ADAC sqlbPFPrefetcherEntryPoint
[9] 0x0900000006FC4C94 RunEDU
db2diag.log:
2013-04-23-03.04.02.444622-420 I1510786A3886 LEVEL: Severe
PID : 10158256 TID : 9768 PROC : db2sysc
15
INSTANCE: DB2INST1 NODE : 015
EDUID : 9768 EDUNAME: db2pfchr (SAMPLE) 15
FUNCTION: DB2 UDB, buffer pool services, sqlb_verify_page,
probe:6
MESSAGE : ZRC=0x87020036=-2029912010=SQLB_BADHDR "Bad Page
Header"
DIA8547C An error occurred in a database page header.
DATA #1 : String, 64 bytes
Error encountered trying to read a page - information follows :
DATA #2 : String, 23 bytes
Page verification error
DATA #3 : Page ID, PD_TYPE_SQLB_PAGE_ID, 4 bytes
75042
DATA #4 : Object descriptor, PD_TYPE_SQLB_OBJECT_DESC, 88 bytes
Obj: {pool:4;obj:227;type:128} Parent={4;227}
lifeLSN: 0423030352951969
tid: 0 0 0
extentAnchor: 19008
initEmpPages: 16
poolPage0: 55408
poolflags: 6112
objectState: 27
lastSMP: 0
pageSize: 16384
extentSize: 16
bufferPoolID: 2
partialHash: 2162360324
bufferPool: 0x0700000031478800
pdef: 0x070000004dad6060
DATA #5 : Bitmask, 4 bytes
0x00000002
DATA #6 : Page header, PD_TYPE_SQLB_PAGE_HEAD, 48 bytes
pageHead: {tbspSeed:4;obj:74;type:128} PPNum:75042 OPNum:82
begoff: 48
datlen: 16336
pagebinx: 7308
revnum: 1280
pagelsn: 0423024730736051 flag: 2
future32: 0
cbits1to31: 0
cbits32to63: 0
DATA #7 : Bufferpool globals, PD_TYPE_SQLB_GLOBALS, 1256 bytes
dbcb: 0x07800000007b82c0
bpcb: 0x07000000300e96a0
ptbl: 0x0700000030109840
eduType: SQLB_EDU_PREFETCHER
eduCB: 0x07000001e03bc8e0
qryData: 0x0000000000000000
qryDataSz: 0
qryDataPos: 0
contQryData: 0x0000000000000000
contQryDataSz: 0
contQryDataPos: 0
bglobals_flags: 200000
dbmon_cb: 0x07000001e03ced80
eduId: 9768
curPfQ: 3
curRemHateListCounter: 8755555
debugInfo: 0x0000000000000000
pCurRecLsn: 0x0000000000000000
clnrCB: 0x0000000000000000
prefetchPriority: 0
agentPriorityWeight: 00
staticStr:
numPFRequestsHeld: 1
memAccessCount:
m_bIsInitialized: true
m_iDisabled: 2222
m_iAccessCount: 0
CALLSTCK: (Static functions may not be resolved correctly, as
they are resolved to the nearest symbol)
[0] 0x090000000700E0EC pdLog + 0xE8
[1] 0x090000000981C630
sqlbLogReadAttemptFailure__FUiP16SQLB_OBJECT_DESCT1P9SQLB_PAGEib
UlT1PcP12SQLB_GLOBALS + 0x194
[2] 0x090000000981C3A8
sqlbLogReadAttemptFailure__FUiP16SQLB_OBJECT_DESCT1P9SQLB_PAGEib
UlT1PcP12SQLB_GLOBALS@glue4ED +
0x9C
[3] 0x09000000073A679C
sqlb_verify_page__FP9SQLB_PAGEP16SQLB_OBJECT_DESCUiT3P12SQLB_GLO
BALSPUl + 0xA4
[4] 0x09000000084D1D58
sqlbReadAndReleaseBlock__FP11SQLB_FIX_CBP20SQLB_BLOCK_VICTIM_CBU
iT3P11SQLB_pfMisc + 0x100
[5] 0x09000000073DE070
sqlbProcessRange__FP16SQLB_OBJECT_DESCUiT2P11SQLB_pfMisc + 0x2E0
[6] 0x0900000006E0078C
sqlbProcessRange__FP16SQLB_OBJECT_DESCUiT2P11SQLB_pfMisc@glueCFD
+ 0x7C
[7] 0x090000000BBF90C0
sqlbPFPrefetcherEntryPoint__FP16sqbPrefetcherEdu + 0x20C
[8] 0x090000000717ADAC
sqlbPFPrefetcherEntryPoint__FP16sqbPrefetcherEdu + 0x8
[9] 0x0900000006FC4C94 RunEDU__16sqbPrefetcherEduFv + 0x2C
2013-04-23-03.04.02.477623-420 E1514673A846 LEVEL:
Critical
PID : 10158256 TID : 9768 PROC : db2sysc
15
INSTANCE: DB2INST1 NODE : 015
EDUID : 9768 EDUNAME: db2pfchr (SAMPLE) 15
FUNCTION: DB2 UDB, buffer pool services,
sqlbLogReadAttemptFailure, probe:10
MESSAGE : ADM14001C An unexpected and critical error has
occurred: "BadPage".
The instance may have been shutdown as a result.
"Automatic" FODC (First Occurrence Data Capture) has been
invoked and
diagnostic information has been recorded in directory
"/home/db2inst1/db2dump/FODC_BadPage_2013-04-23-03.04.02.463183_
0015/".
Please look in this directory for detailed evidence
about what
happened and contact IBM support if necessary to
diagnose the
problem.
2013-04-23-03.04.02.497421-420 I1515520A652 LEVEL: Severe
PID : 10158256 TID : 9768 PROC : db2sysc
15
INSTANCE: DB2INST1 NODE : 015
EDUID : 9768 EDUNAME: db2pfchr (SAMPLE) 15
FUNCTION: DB2 UDB, buffer pool services, sqlb_verify_page,
probe:6
MESSAGE : ZRC=0x87020036=-2029912010=SQLB_BADHDR "Bad Page
Header"
DIA8547C An error occurred in a database page header.
DATA #1 : String, 33 bytes
Page verification error occurred.
DATA #2 : Dumped object of size 16384 bytes at offset 0, 92
bytes
/home/db2inst1/db2dump/FODC_BadPage_2013-04-23-03.04.02.463183_0
01
5/10158256.9768.015.dump.bin
2013-04-23-03.04.02.499468-420 I1516173A216 LEVEL: Severe
PID:10158256 TID:9768 NODE:015 Title: SQLB_PAGE
Dump File:
/home/db2inst1/db2dump/FODC_BadPage_2013-04-23-03.04.02.463183_0
01
5/10158256.9768.015.dump.bin
2013-04-23-03.04.02.517664-420 I1516390A781 LEVEL: Severe
PID : 10158256 TID : 9768 PROC : db2sysc
15
INSTANCE: DB2INST1 NODE : 015
EDUID : 9768 EDUNAME: db2pfchr (SAMPLE) 15
FUNCTION: DB2 UDB, buffer pool services, sqlb_verify_page,
probe:6
MESSAGE : ZRC=0x87020036=-2029912010=SQLB_BADHDR "Bad Page
Header"
DIA8547C An error occurred in a database page header.
DATA #1 : String, 46 bytes
Container information : path, contID, mapInfo.
DATA #2 : File name, 38 bytes
/home/db2inst1/NODE0015/DWP01TST/temp16k
DATA #3 : Container ID, PD_TYPE_SQLB_CONTAINER_ID, 4 bytes 0
DATA #4 : SQLB_MAP_INFO, PD_TYPE_SQLB_MAP_INFO, 16 bytes
offset: 75058 length: 1
blkSize: 14 |
