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DCMT Enhancements for Automatic Tuning

This release provides the following new DCMT command enhancements specific to automatic tuning:

DCMT DISPLAY AUTOTUNE Command

The DCMT DISPLAY AUTOTUNE command shows statistics related to automatic tuning.

DCMT DISPLAY AUTOTUNE Syntax

The following diagram shows the syntax for the DCMT DISPLAY AUTOTUNE command:

►►─ DCMT ─┬───────────────────┬───────────────────────────────────────►
          └─ broadcast-parms ─┘

 ►── Display AUTotune ─┬────────────┬─────────────────────────────────►◄
                       ├─ * ────────┤
                       ├─ DPE ──────┤
                       ├─ RCE ──────┤
                       ├─ RLE ──────┤
                       └─ SYSlocks ─┘
DCMT DISPLAY AUTOTUNE Parameters

This section describes the parameters for the DCMT DISPLAY AUTOTUNE command:

broadcast-parms

Executes the DCMT command on all or a list of data sharing group members. For more information about the broadcasting and broadcast-parms syntax, see How to Broadcast System Tasks in the System Tasks and Operator Commands Guide.

*

Displays graphs and summary information for all parameters for which automatic tuning is enabled.

DPE

Displays the graph and summary information for the DPE count parameter.

RCE

Displays the graph and summary information for the RCE count parameter.

RLE

Displays the graph and summary information for the RLE count parameter.

SYSlocks

Displays the graph and summary information for the SYSLOCKS parameter.

Note: If no parameter type is specified, summary information for all parameters is displayed.

Example: Automatic Tuning Results

The following command displays summary information about all parameters being automatically tuned:

DCMT D AUTOTUNE *** Display Autotune *** AUTOTUNE last save time (time zone: UTC): 2009-12-21-15.10.12.528239 Parameter|Lowest |Highest |SYSGEN |Current | Next Name | HWM | HWM | Value | Value |Value ------------+-----------+-----------+-----------+-----------+----------- SYSLOCKS | 140 | 160 | 600 | 600 | 454 ------------+-----------+-----------+-----------+-----------+----------- RLE | 334 | 353 | 5000 | 5000 | 3841 ------------+-----------+-----------+-----------+-----------+----------- RCE | 303 | 312 | 5000 | 5000 | 3833 ------------+-----------+-----------+-----------+-----------+----------- DPE | 497 | 517 | 600 | 600 | 588 ------------+-----------+-----------+-----------+-----------+-----------

Last save time

Indicates the date and time that tuning information was last saved. The value is in the UTC timezone.

Parameter Name

Indicates the name of the parameter being tuned.

Lowest HWM

Indicates the lowest high-water mark recorded in the last 32 collection intervals.

Highest HWM

Indicates the highest high-water mark recorded in the last 32 collection intervals.

Current HWM

Indicates the high-water mark for the current time interval.

SYSGEN Value

Indicates the value assigned to the parameter in the system definition when the DC/UCF system was last started.

Current Value

Indicates the value assigned to the parameter when the system was last started.

This value will be assigned to the parameter when the system is next started if it terminated abnormally.

Next Value

Indicates the value that will be assigned to the parameter when the system is next started if it terminated normally.

The following command displays automatic tuning information for only the SYSLOCKS parameter.

DCMT D AUTOTUNE SYSLOCKS *** Display Autotune *** AUTOTUNE last save time (time zone: UTC): 2009-12-21-15.06.12.460692 Parameter name: SYSLOCKS 160| _ _ _ |_ # # _ _ _ _ _ _ _ _ # _ _ _ _ _ _ _ _ _ _ _ |# # # # # # # # # # # # # # # # # # # # # # # _ _ _ _ _ _ _ _ _ |# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # |# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # |# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # |# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # |# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # |# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # 0L#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_ Summary ------- Original SYSGEN value: 600 Highest HWM: 160 Current value: 600 Lowest HWM: 120 Next value: 454 Current HWM: 120

In addition to the fields shown in a summary display, a detail display includes the following information.

Graph

Shows the high-water mark recorded for the parameter in each of the last 32 time intervals.

The horizontal axis represents time intervals, in oldest to newest order.

The vertical axis represents HWM values. The scale adjusts to accommodate the range of HWM values being displayed.

DCMT VARY AUTOTUNE Command

Use the DCMT VARY AUTOTUNE command to reset auto-tuning statistics and disable auto-tuning.

DCMT VARY AUTOTUNE Syntax

The following diagram shows the syntax for the new DCMT VARY AUTOTUNE command:

►►─ DCMT ─┬───────────────────┬───────────────────────────────────────►
          └─ broadcast-parms ─┘

 ►── Vary AUTotune ─┬─ ALL ──────┬─┬─ RESET ─┬────────────────────────►◄
                    ├─ DPE ──────┤ └─ OFF ───┘
                    ├─ RCE ──────┤
                    ├─ RLE ──────┤
                    └─ SYSlocks ─┘
DCMT VARY AUTOTUNE Parameters

This section describes the parameters for the DCMT VARY AUTOTUNE command:

broadcast-parms

Executes the DCMT command on all or a list of data sharing group members.

For more information about broadcasting and broadcast-parms syntax, see How to Broadcast System Tasks in the System Tasks and Operator Commands Guide.

ALL

Varies auto-tuning for all tuned parameters.

DPE

Varies auto-tuning of the DPE count parameter.

RCE

Varies auto-tuning of the RCE count parameter.

RLE

Varies auto-tuning of the RLE count parameter.

SYSlocks

Varies auto-tuning of the SYSLOCKS parameter.

RESET

Resets historical information for the specified parameter so that tuning is based on future values only.

OFF

Disables automatic tuning for the specified parameters. Auto-tuning is disabled only for the current execution of the DC/UCF system.

Note: To permanently disable automatic tuning, you must change your system definition.

Example: Reseting Statistics

The following command resets statistics for auto-tuning SYSLOCKS:

DCMT V AUTO SYSLOCKS RESET SYSLOCKS has been reset

DCMT DISPLAY CHANGE TRACKING Command Output

Output from the DCMT DISPLAY CHANGE TRACKING command shows the amount of space consumed by automatic tuning.

DCMT D CHANGE TRACKING Change Tracking - Status Delete PageCnt Target-FileCnt Actual-FileCnt ACTIVE OFF 21 4 2 SYSTRK contents Size PagCnt Pct Last Updated (time zone: UTC) DMCL + file information 36964 5 24% 2009-12-21-12.25.59.212961 Permanent area statuses 0 0 0% 2009-12-21-12.26.00.543069 Journal status overrides 0 0 0% 2009-12-21-12.25.59.234894 Autotune overrides 1400 1 5% 2009-12-21-15.14.15.539878 Control information 30192 4 19% N/A -------------------------- ------ ------ ---- Total: 68556 10 48% File Name MirrorStat MODE ErrStat PagSize PagCnt Fl-Type DD-Name SYSTRK2 ACTIVE Clos 0 7548 21 non-VSAM SYSTRK2 DSname: DBDC.SYSTEM73.SYSTRK2 DISP=SHR VOLSER:CULL05 FORMAT datetime (time zone: UTC) 2009-12-19-14.06.15.881502 CONTROL datetime (time zone: UTC) 2009-12-21-12.25.56.579801 SYSTRK1 ACTIVE Clos 0 7548 21 non-VSAM SYSTRK1 DSname: DBDC.SYSTEM73.SYSTRK1 DISP=SHR VOLSER:CULL05 FORMAT datetime (time zone: UTC) 2009-12-19-14.06.15.853321 CONTROL datetime (time zone: UTC) 2009-12-21-12.25.56.579801 Next value: 454 Current HWM: 14