IMS Control Block Table (CBT) Pools

The IMS CBT storage manager (also known as the DFSBCB storage manager) manages pools of fixed-length control blocks.

All CBT pools can be displayed by issuing the /DISPLAY POOL CBT. Issuing the /DISPLAY POOL command with other keywords, such as DBB, DCC, DEP, DISP, FP, GEN, OSAM, SUM, and others, limits the display of the CBT pools to those related to the functional area of IMS that the keyword represents.

All of the CBT pools are briefly described in the following alphabetical list.

AAB
Obsolete CBT entry
ADSC
Fast Path area data set control block
AESL
Fast Path DEDB ADS list
AHDR
ETO autologon LU header/ autologon hash table synonym
APST
Partition specification table - above the line
ATPW
Attach catalog PSB work area block
AWE
Asynchronous work element
BCPT
Checkpoint id table
BQEL
ISAM/OSAM/VSAM buffer queue element
BXQE
BCB queue elements for use by DFSBCBxx modules only
CATR
IMS catalog request block
CBLK
Used in place of message queue to keep track of CPI-C scheduling requests
CCB
Conversational control block
CFEZ
Block used to store local parms for DC trace re-entrancy
CLLE
Common latch list element
CM24
Common work unit, 24-bit
CMWU
Common work unit
CRSP
OM command response block
CSAG
Callable services anchor block (CSAB) - global storage
CSAL
Callable services anchor block (CSAB) - local stoarge
CSWA
Common system work area - global storage
CTBW
Communication terminal block work area
CULE
Common use list element
D1WA
Dispatcher work area 1
DACT
DL/I call accounting block
DBBD
Database (DDIR) descriptor
DBPB
Data base purge block
DBRC
DBRC work area
DCM
Obsolete CBT entry
DDIR
DMB directory entry
DDRE
DMB directory extension
DESC
LU 6.2 descriptor block
DG2W
Global dispatcher area
DL2W
Local dispatcher area
DLWA
DL/I private work area
DMAC
Fast Path DEDB area control block for dynamic areas
DMHR
Fast Path VSO dynamic DHMRs for write staging area
DPST
Dependent region PST
DPXB
Dispatcher extension block
DSME
Fast Path data space mapping entry
DSML
Fast Path data space mapping list
EMAC
Obsolete CBT entry
EPST
Fast Path extended PST
EQEL
Resolve indoubt structure queue element
EZS
External connection status element
FEIB
Front end message switch interface block
FMMC
Fast Path control block to contain VSAM extents
FNCB
Fast Path notify control block
FPB6
Fast Path DBFBPND6 block for FP 64-bit buffer pools
FPCP
Fast Path command parameter list
FSRB
Fast Path SRB
GDS
Obsolete CBT entry
GESE
Global external subsystem entry
GIOB
Global IOSB
GOWA
Global OSWA
GPNT
Fast Path global name table
GQMW
Global queue manager work area
GSAV
Global save area
HSHE
Hash table element header
HSHS
Hash table slot header
HTEB
BPE LFS hash table services: hash table element block, CTL private
HTED
BPE LFS hash table services: hash table element block, DLI private
IAFP
IAFP dataset control block
IBKD
Interface Block for user exit services in DL/I region private storage. The IBKC control block is used for working storage and a parameter list when invoking a user exit through IMS DFSUSRX user exit service.
IBKP
Interface Block for user exit services in control region private storage. The IBKP control block is used for working storage and a parameter list when invoking a user exit through IMS DFSUSRX user exit service.
IDT
Identify table entry
IEQE
Inflight/indoubt data buffers
IOSB
I/O supervisor block
IPST
System PST in DLI/SAS private, 31-bit storage
IRLM
IRLM parameter area
KLSD
LSO dependent control block
L56X
Fast Path DBCTL log record
LCLL
Local common latch list element (local storage)
LCRE
Local current recovery entry
LG24
An LSAV below the 16m line
LGND
Logon descriptor control block sets
LGWA
Log work area
LGWX
Log work area extension (private)
LPNT
Fast Path local name table
LPST
Local PST block
LQB
Local queue block
LQMW
Local queue manager work area
LRA
Obsolete CBT entry
LS24
24-bit quick block, local save area / AWE
LSAV
Local save area
LSWA
Local system work area
LUB
LUB pool below 16 MB line for LU 6.2
LXB
Dynamic link extension block for VTAM® and TCP/IP links. The LXB control block is mapped by the LXB copy.
MMCL
OSAM Media Manager Interface module parameter list.
MMPL
Media Manager Services parameter list.
MMRQ
Media Manager Request Element prefix plus Media Manager Request Element.
MPB
Obsolete CBT entry
MPCB
PCB block for MSC bandwidth. The MPCB control block is mapped by the DFSMSPCB macro.
MSCL
MSC logical link control blocks: LLB, two LTBs, and a CRB. The MSCL control block is mapped by the DFSMSCL macro.
MSCP
MSC physical link control blocks: LCB and CTT. The MSCP control block is mapped by the DFSMSCP macro.
MSEB
Work area for the TM and MSC Message Routing and Control User exit routine (DFSMSCE0). The MSEB work area is mapped by the DFSMSCEB macro.
MSGP
Message pool
MUTE
OTMA MCB user table entry
OCMD
OM command instance block
OFB
Obsolete CBT entry
OLRK
OLR KSDS update entry
OSSA
OSAM save area block.
OSWA
OSAM work area (IOMA)
OTDD
OTMA destination descriptors
OTMD
OTMA member descriptors
PCIB
Partition CIB
PDEX
Partition directory extension
PDIR
PSB directory entry
PF62
Message prefix block for LU 6.2
PFQE
CQSPUT failure queue element
PGMD
Program (PDIR) descriptor
PST
Partition specification table
QAB
QAB pool for LU 6.2
QLST
Work area to hold queue manager parameter list
QLTC
DEDB and area quiesce latch blocks for DEDB Alter
QMBA
Queue manager buffer area (large message)
QMBS
Queue manager buffer area (small message)
QQSN
Queue space notification area
QS24
Temporary save area set with parm areas - 24-bit storage
QSAV
Temporary save area set with parm areas - 31-bit storage
RACW
RACF® work area used for racinit, fracheck, etc.
RBAT
Fast Path VSO RBA update table entries
RCNT
Remote communication name table. The RCNT control block is mapped by the RCNT copy.
RCTD
Fast Path routing code (RCTE) descriptor
RCTE
Fast Path routing code table entry
RECA
VTAM receive any buffer
RPST
Restart partition specification table
RRE
Residual recovery entry
RSCX
Resource extension block
SAA
Obsolete CBT entry
SAP
Save area prefix
SIDX
Subsystem index entry
SLOG
DC monitor work area
SMB
Scheduler message block
SOPB
Sign-on parameter block
SPQX
SPQB extension block
SQOF
Shared queues overflow hash table element
SRA
Obsolete CBT entry
SRBC
Common SRB pool
STAT
DBCTL and DRA statistics area
STB
Obsolete CBT entry
STTR
DL/I trace stacks
SVPG
System service parameter lists - global
SVPL
System service parameter lists - local
TCBT
TCB table
TDBC
Obsolete CBT entry
TDCB
Obsolete CBT entry
TIB
TIB pool for LU 6.2
TLS
Transaction level statistics area
TPIP
TPIPE pool for OTMA
TRND
Transaction (SMB) descriptor
TT24
Trace table (24-bit storage)
TT3P
Trace table (31-bit, private storage)
TTAB
Trace table (31-bit storage)
UOWE
Unit of work table entry
USRD
User descriptor control blocks
USTB
Obsolete CBT entry
UXIC
User exit instance (common)
UXIP
User exit instance (private)
UXSC
User exit static area (common)
UXSP
User exit static area (private)
VRPL
VSAM RPL/save area stack
VTCB
VTAM session control block
VWA
Volatile work area
WLMB
Work area of parameter list for the Workload Manager classification service.
X124
DL/I pool below 16m line
XMCI
Cross memory itask block
XMCL
Local XMCI block (ctl private)
XPST
Extended PST area (dependent region)
XT62
LU 6.2 and OTMA PST extension
YQAB
OTMA queue anchor block