Event Control Block (ECB) Information

152

#WTL;

#WTL REPLY ECB

#WTL REPLY.

153

*LOGON*;

VTAM LOGON ECB

VTAM logon ECB

161

*TIMER*;

TIMER ECB

Almost always waited on by the run unit service driver (RHDCRUSD), OPER, and DDS VTAM.

32

3280 RTY;

3280 RETRY TIMER

The terminal driver is waiting to retry the request to the 3280.

1

BCRECB

Wait for database buffer pool.

Increase number of buffers. If this is a shared buffer, change to non-shareable buffers. Increase the DB page size.

2

BMESECB

Wait for buffer.

Handle it the same way as ECB 1.

3

BMEXECB

Wait for exclusive use of a buffer.

Waits on this ECB can be caused by contention for the space management page (SMP). Verify the database pages are less than 70% full.

Handle the same was as ECB 1.

164

BTAM I/O;

DDS BTAM I/O ECB

Distributed database waits for BTAM I/O to complete.

128

CCEECB

DBRC Unsolicited read

129

CCEUPECB

The database resource controller task (DBRC) is up.

34

CCEVRECB;

VARY TABLESPACE ECB

Obsolete

130

CKUECB

Check user, wake up task.

131

CKUECBT

Check user

132

CSAEXECB

External ECB posted by external task.

4

CSALDECB

Loader single thread wait.

This should be a very brief wait. The single threading acts as a tie breaker for simultaneous requests to load.

5

CSALFECB

DCLOG single thread wait.

Reduce the number of user writes to logs, if any.

Only allow critical dumps to be written to the log.

If using Perfmon on z/OS, write the records to SMF.

If using Perfmon, reduce statistics collection to a minimum.

Move the log area to faster device.

Balance channels.

Balance packs.

133

CSALGECB

Log full ECB

Wait for a batch job to offload the log.

CV waits while waiting for the offload.

If this wait is prolonged, tasks will timeout.

Check that the manual procedures are being followed properly. Verify the log is not being overused. Send statistics to SMF rather than to the log. Turn off snaps.

45

CSASCECB;

SCRATCH SNGL THREAD

Scratch single thread ECB

The task is waiting for single thread access to the scratch area.

To improve performance, do the following:

• Reduce the usage of scratch area by applications
• Increase the scratch area page size
• Use 'VIO' data sets for scratch area
• Use SCRATCH IN STORAGE YES.

24

CSASMECB;

SMTECB

Storage pool wait.

Storage is requested by storage type rather than by pool number. The SMTECB is waited on when there is insufficient storage of the type requested in any of the pools which are sysgenned to support that type. This means that DC may not be short on storage when the SMTECB is waited on.

Usually there is a high Short on Storage (SOS) count.

Increase the size of the storage pool.

Reduce the size and number of storage requests.

Reduce max tasks/ number of EREs.

Reallocate space from underutilized pools.

In general a few large storage pools are better than many small ones.

6

CSATJECB

Obsolete

178

DB V TSK;

DB HELOT TSK EXTECB

194

DBGROUP;

DBGROUP ECB

DB group reply ECB (HPCS).

This ECB is used to enqueue a request for back-end services in a Parallel Sysplex environment.

Indicates RHDCCFIM (Coupling Facility Interface Module) is waiting on a reply from the back-end.

176

DBIO DRV;

D/B I/O WRT DRV EXT

Obsolete

182

DBIO DRV;

DB PREFETCH DRV EXT

There is one ECB for each database read driver.

168

DBIO RDE;

DBIO READ ECB

204

DBIO SD;

DBIO SVCE DRIVER

DBIO Service Driver ECB

This ECB is part of the ECB-list where the Page Locking Service Driver module is waiting in its main processing loop. When posted, it purges the XES buffers. This ECB used as part of a Parallel Sysplex environment.

181

DBIO TSK;

DB I/O TASK ECB

167

DBIO WRT;

DBIO WRITE ECB

30

DBRCMSTR;

DBRCECB IN MSTR

Wait for the database resource controller to initialize at startup, or clean up at shutdown.

A long wait at shutdown means there is database work in progress, such as:

• A batch run-unit
• A conversational task
• A shutdown autotask

159

DBRCWTOR;

DBRC WTOR ECB

Always waited on by *DBRC* (RHDCDBRC).

166

DDS ATTN;

DDS ATTENTION ECB

Obsolete

162

DDS READ;

DDS VTAM READ ECB

Distributed database waits for a VTAM read to complete.

163

DDS WRIT ;

DDS VTAM WRITE ECB

Distributed database waits for a VTAM write to complete.

8

DMCJECB

Journal buffer wait.

Move journal files to a faster device.

Stop journaling the after images of queue records.

Increase the number of journal buffers.

9

DMCJHECB

Journal buffer wait.

Used only during startup, shutdown, and journal swap.

Handle the same way as ECB 8.

160

DMCJHECB;

DMCJHECB EXTRN WAIT

External wait on journal header.

51

DPRQECB

DCMT quiesce area ECB

IDMSDBMS may be waiting on this ECB when the AREA is quiescing.

7

ECEECB

Enqueue on resource name.

If this is a user resource, consult with your users to verify their response time. If the response time is slow, investigate the task to determine why the enqueue is occurring.

The SYSGEN task statement "MAX CONCURRENT" may be more appropriate; or the resource could be held longer than is required.

134

EREECB

External run unit ECB.

136

ESECKECB

Post the check user task.

135

ESEECB

External system ECB.

An external run unit request for service is made.

10

FCBXECB

DBIO waiting on a prior I/O (DOS).

Move the DB area.

Increase the page size.

Balance channels.

Balance packs.

Split heavily used files into multiple files and put the files on separate packs.

Consider converting the file to VSAM.

48

GLQTEECB;

GLOBAL QUEUE TABLE

Global QUEUE table entry ECB

DC-internal single thread ECB

208

GPRXLOCK;

LMGR PRX;

GPRXLCK

LMGR Proxy Recovery Lock ECB

This ECB used in a Sysplex environment to indicate it is waiting on a Proxy Recovery Lock.

197

GTXNLOCK;

GBL DBKY

LMGR global transaction lock ECB.

This ECB is waited on by LMGR (Lock Manager) when attempting to access a globally-locked resource such as an area, a page or a db-key.

41

HELOTWRK;

DB V TSK;

D/B HELOT TASK ECB

HELOT (database VARY TASK) waits on this ECB for work.

196

HPCACHE;

HPCACHE ECB

HPCS cache ECB.

Waiting on a cache I/O to complete, either a read HPCS cache buffer into local buffer or a write of a buffer to the HPCS cache. Used by RHDCCFIC (Coupling Facility Interface Common routines).

195

HPLIST;

HPLIST ECB

HPCS list ECB.

This ECB is used by RHDCCFIC (Coupling Facility Interface Common routines) to wait for completion of an asynchronous write to a list structure.

Also used by RHDCCFIM (Coupling Facility Interface Module) to indicate a 1 second wait after message DC215010 has been issued.

The above message indicates the list structure is full and there is a 1 second before retrying the write. Eventually increase the size of your list structure in your CFRM coupling data set.

137

ICEECB

Interval control element.

The ICE is used to support timer waits.

138

IDBSECB

Obsolete

11

IDWUPECB

Obsolete

12

IIEPECB

Obsolete

179

ILE-LOCK;

ILE LOCK ECB

0

INT ECB

0 or any invalid ECB

This is a catch all for ECBs. If a type 0 ECB requires analyzing, do the following:

1. Get a system dump

2. Identify the ECB by its address

3. Determine which module or piece of storage contains the ECB

4. Determine which task owns the storage

43

IODRWORK;

DBIO DRV;

DB PREFETCH DRV ECB

Database I/O read driver is waiting for a read to complete. (CCERDECB)

There is one ECB for each database read driver.

39

IODWWORK;

DBIO DRV;

D/B I/O WRT DRV ECB

Obsolete

31

JBCHECB

(JBEHECB) Journal control block header.

Rollback is waiting to lock the journal for recovery.

13

JCBXECB

Journal buffer wait.

Handle the same way as ECB 8.

177

JOUR DRV;

JOURNAL DRV EXT ECB

180

JRNL FRG;

JRNL DRV FRAGMENT

170

JRNL I/O;

DBIO JRNL WRITE ECB

Database I/O journal write

186

JRNLW ER;

JNLWRTER;

JOURNAL WRITE ERROR

40

JRNLWORK;

JOUR DRV;

JOURNAL DRIVER ECB

Obsolete

158

LDR DECB;

LOADER DECB

203

LMGR SD;

LMGR SVCE DRIVER

LMGR Service Driver ECB

A request from another data sharing member for lock manager work is done.

50

LRBKECB

LRBK unrecovered transaction ECB (Rollback ECB)

ECB used for the synchronization and processing of unrecovered transactions.

139

LREECB

Local run unit

ECB used by external run unit communication.

15

LTERM;

LTEECB

Waiting for a particular logical terminal to become available, such as a printer.

17

LTTECB

Waiting for action on any logical terminal.

The LTTECB serves to catch changes in the state of a logical terminal through DCMT VARY LTERM or DCMT VARY PRINTER.

16

LTTMSECB

Logical terminal needs service.

Task 0 (MSTR) is normally waits on this ECB because it is waiting for work.

14

LTXNLOCK;

DBKEY

Lock Manager Local transaction lock ECB.

Used to wait on a lock manager resource such as DBKEY, AREA, or PAGE.

Lower the number of max concurrent tasks.

Lower the number of max tasks.

Examine the application's use of the database record.

Revise the application programs to interrogate status code returned from each database request and include the appropriate retry logic.

140

MLEPECB

Multi-thread line entry is used for BTAM support.

The MLEPECB is for the external polling delay.

141

MLESECB

Multi-thread line entry is used for BTAM support.

The MLESECB is for external service for the line.

183

MPMODE;

MP MODE WAIT ECB

Multi-tasking single thread coding ECB.

205

MSGECB1

Quiesce AREA ECB 1 (Timer ECB)

This ECB used in module RHDCDBRC to deal with DCMT QUIESCE AREA processing.

206

MSGECB2

Quiesce AREA ECB 2 (Terminate ECB)

This ECB used in module RHDCDBRC to deal with DCMT QUIESCE AREA processing.

207

MSGECB3

Quiesce AREA ECB 3 (Helot-2 task ending ECB)

This ECB used in module RHDCDBRC to deal with DCMT QUIESCE AREA processing.

142

MSGRECB

Wait for message to complete.

37

OBCECB;

UNKNOWN ECB TYPE

Obsolete

35

OMCGBECB;

UNKNOWN ECB TYPE

Obsolete

36

OMCGIECB;

UNKNOWN ECB TYPE

Obsolete

18

PDTECB

Program pool wait.

Increase the size of the program pool.

Take space from an underutilized pool and allocated it to this program pool.

On an XA operating system, move XA programs to an XA pool

21

PLE;

PLESECB

Physical line needs service.

The PLESECB is posted to notify terminal drivers that one or more terminals require service.

This ECB is almost always waited on by drivers.

143

PLE2PECB

Remote 3270 terminal ECB.

22

PLE9RECB

Simulated 3270 terminal.

This means the 3270 terminal simulator is waiting for an I/O to disk to complete.

This ECB is waited on only briefly. If it waited on for any length of time, it is possible that someone is running a stress test. Check the set up of their script.

If this occurs at startup, it could be due to startup autotasks that read long files. Change the startup autotasks to run one at a time.

144

PLEZTECB

UCF ECB posted every 60 seconds by the timer routine in the system dependent module.

46

PM DRVR;

PERFMON SERVICE DRV

Perfmon service driver ECB

Waited on by module PMONCIOD (Perfmon I/O Service Driver) during system shutdown processing. Module PMONCROL (Perfmon Interval Monitor) posts this ECB.

187

PM DRVR;

PERFMON SERVICE DRV

Performance monitor service driver waiting for work.

188

PMONLINE;

PM ONLRQ;

PERFMON ONLINE RQST

42

PRGEAREA;

DB PURGE;

QUIESCE TABLESPACE

The database resource controller is quiescing the area.

19

PROGRAM;

PDELOCK

Single thread PDE

This ECB is only used when the program definition is being updated. If this ECB is being waited on, do the following:

• See if the same task/program is in control
• If the same task/program is in control, check for a load request inside of a loop.

Check http://ca.com/support for any outstanding maintenance.

20

PROGRAM;

PDEECB

Loader is waiting on this program because one of the following occurred:

• There is insufficient room to load it.
• It is being quiesced in response to a VARY NEW COPY command.

This ECB is also waited on when a program has been overlaid and must be reloaded before re-dispatching the task that uses it.

145

PRTSECB

Printer in service.

148

PTE6ECB

Start/stop I/O terminal ECB.

Almost always waited on by start/stop (dialup) driver.

147

PTEPECB

Pause that refreshes (hiccup wait). This is a wait so other tasks can run. This task remains dispatchable.

23

PTERM;

PTERECB

Physical terminal request.

Waiting for a front-end printer to become available.

The terminal handler waiting for a request to complete, usually a read. Check the following conditions: :ol comp.

1. Determine if the active task is pseudo-conversational.

2. If the task is not pseuedo-conversational, ensure that it is intended to be a conversational task.

3. Verify the additional resources such as storage, task slot, and space in the program pool are available without impacting the rest of the workload.

146

PTEUECB

Unsolicited terminal read.

Posted by terminal drivers.

47

QDTSTECB;

QUE SNGL;

QUEUE CLEANUP TASK

QUEUE single-thread ECB

During CV-startup, QUED must have exclusive use of the QUEUE area. To prevent deadlocks, all QUEUE processing is suspended until QUED finishes. The QUEUE Manager (RHDCQUEM) is waiting on this ECB until it is posted by QUED.

184

QUIES AR;

DB QUIES;

QUIESCE DB AREA

149

QWEECB

External ECB for the queue function.

Used when a task issues a 'GET QUEUE WAIT' and there is no queue record.

Posted when a 'PUT QUEUE' is issued to the queue in question.

150

RCEECB

General resource ECB.

53

RESYNC;

Resynchronization

Resynchronization management ECB.

The ECB is waited on by TMGR (Transaction Manager) during resynchronization processing.

151

RUHFECB

Run unit header ECB

Posted by free run unit.

29

RUN-UNIT

VIBECB

Wait until no other run-unit is using the area before turning on the area lock.

49

SCBECB

Obsolete

191

SCBECBE;

SCBECB;

SCBECB EXT

Job management spooler communication block.

38

SDCSECB;

SERVICE DRIVER ECB

Each service driver has one of this ECB type.

It means waiting for work.

This ECB is almost always waited on.

Posted by RHDCMSTR.

33

SESSION;

MODE GROUP ECB

LU 6.2 is waiting on mode group session.

190

SHUTECB;

CSASDECB;

CSA SHUTDOWN ECB

189

SMFWECB;

SMFWRITE;

SMF WRITE ECB

Waiting for the write of statistics records to SMF complete.

Posted by z/OS. If this ECB is waited on frequently, review SMF buffering, and consider using the DC log for statistics.

185

SUSP RU;

SUSPENDED RUN UNIT

26

TASKID;

TCEECB

TASKID

This is a general purpose ECB associated with a particular task. Verify the same task is recurring. If it is the same task, get a system dump and name reoccurring, and if it is, take a dump and identify the source of the of the wait.

25

TCAECB

New task wait.

If a task is attached when DC is at max tasks, it waits on this ECB.

193

TCEECBAF;

TCE SUBTASK AFFINTY

Affinity ECB

209

TCP/IP;

TCP/IP ASYNC. ECB

TCP/IP asynchronous ECB

This ECB is used by RHDCD0IP and RHDCD1IP (Socket Line Driver and Plugin Module) to wait for completion of asynchronous socket calls such as ACCEPT and RECV.

165

TERM I/O;

ANY TRMINAL IO ECB

Always waited on by line drivers.

27

TJHFECB

Obsolete

28

TJHSECB

Obsolete

54

TM REQ;

Txn Req

Transaction request ECB.

The ECB is waited on by TMGR (Transaction Manager) when it is waiting for the completion of a transaction manager request.

52

TXNBECB;

SERIALIZE TXN BRNCH

Transaction branch serialization.

The ECB is waited on by TMGR (Transaction Manager) when serializing use of a transaction branch.

156

USER ECB

If this wait is frequent, check user modules for their use of ECB's.

157

USER ECB;

USER ECBID

169

VSAM CCB;

DBIO DOS VSAM CCB

171

VTAM I/O;

VTAM RCV-ANY (D0EV)

Wait for VTAM receive any.

LU6.2 unsolicited read

154

VTM READ;

VTAM READ INIT ECB

VTAM read ECB

The VTAM drivers are waiting for data from VTAM.

This ECB is almost always waited on.

155

VTM RPL;

VTAM RPL ECB

Waiting for VTAM request parameter list.

If this wait is frequent and prolonged and there are resources available, then the number of RPL's can be increased for faster response time.

200

XCF GROUP;

XCF GROUP ECB

XCF Group ECB

This ECB used to single thread access to XCF group processing during startup or shutdown of a CV in a data sharing environment.

199

XCF MSG;

XCF MESSAGE ECB

XCF Message ECB (SYSPLEX receive ECB).

This type of ECB is waited on by RHDCCFIM (Coupling Facility Interface Module) when messages are exchanged between members of a data sharing group.

202

XES LIST;

XES LIST ECB

XES List ECB

This ECB used in a Parallel Sysplex environment to wait on completion of asynchronous access to a list structure.

198

XES LMGR;

LMGR XES;

XES LMGR ECB

LMGR XES ECB.

This ECB is waited on by LMGR (LOCK Manager) when attempting to acquire a global proxy lock.

201

XES LOCK;

XES LOCK ECB

XES Lock ECB

This ECB used in a Parallel Sysplex environment while waiting on request completion during Obtain, Alter or Release Lock processing in RHDCCFIM (Coupling Facility Interface Module).

192

XIOB ECB;

XIOB ALC;

XIOB ALLOCATION

All XIOB blocks in use. Needed for DB I/O.