gtpo1m2aOperations

ZCACH-Manage Logical Record Caches

Use this command to manage logical record caches.

Requirements and Restrictions

You can enter this command only from the basic subsystem (BSS) when the following parameters are specified:

Format




MODIFY
sets the number of entries defined for the logical record cache in the processor unique logical record cache control record. The number of entries specified here overrides the number of entries specified on the newCache function call that is issued by the application to create the logical record cache. The new number of entries is not active until the specified logical record cache is created.

cache
is the 4- to 12- character alphanumeric name of the target logical record cache. The first character of the logical record cache name must be an alphabetic character.

SIZE entrysize
specifies the number of entries defined for the logical record cache, where entrysize is a decimal number, from 0 to 999 999 999.

DISPlay
displays information about the logical record cache.

CTL
displays the names of the processor's current logical record caches and their addresses from main storage.

FILE
displays the names of the current logical record caches and their assigned sizes as defined in the processor unique cache control record.

ATTributes
displays the attributes of the specified logical record cache and the associated CF if a CF is in use.

SYNonym
displays the synonym chain length information for the specified logical record cache.

COunts
displays the current data collection counters for a specific logical record cache.

CF ENABLE
enables the processor shared caches to use a CF for cache synchronization.

CF DISABLE
disables the processor shared caches from using a CF for cache synchronization.

REMove
removes the cache definition for the specified logical record cache from the processor unique cache control record. This action does not affect the logical record cache that is currently active.

FLush
clears all entries from the processor's logical record cache. There is no notification sent to other processors.

DELete
deletes the specified logical record cache from the processor.

Additional Information

Online help information is available for this command. To display the help information, enter one of the following:

ZCACH HELP

ZCACH ?

Examples

The following information is displayed in the examples:

CALLS
The number of readCacheEntry calls.

CASTOUTS
The number of times a cache tosses out a valid entry to make room for another entry.

DUPLICATE HASH
The number of times an entry was not added to a cache because its 16 byte name was the same as an entry already in the cache.

INVALIDATED
The number of times a cache entry was invalidated by another processor.

MISSED
The number of readCacheEntry calls that did not find a valid entry.

UPDATES
The number of times a readCacheEntry call caused a cross invalidate to the CF.

The following example shows the names of the current logical record caches and their addresses.

+--------------------------------------------------------------------------------+
|User:    ZCACH DISP CTL                                                         |
|                                                                                |
|System:  CACH0002I 19.29.52 CACHE CONTROL AREA DISPLAY                          |
|         NAME TPF_FS_DIR     ,ADDR 05073000                                     |
|         NAME TPF_FS_INODE   ,ADDR 05287000                                     |
|         DISPLAY COMPLETE                                                       |
+--------------------------------------------------------------------------------+

The following example shows the names of the current logical record caches and their assigned sizes as defined in the processor unique cache control record.

+--------------------------------------------------------------------------------+
|User:    ZCACH DISP CTL FILE                                                    |
|                                                                                |
|System:  CACH0026I 09.41.56 CACHE CONTROL RECORD DISPLAY                        |
|         NAME  CACHE12456, ENTRY COUNT  000012456                               |
|         DISPLAY COMPLETE                                                       |
+--------------------------------------------------------------------------------+

The following example shows the attributes for logical record cache TPF_FS_DIR, which is using CF CFLOCK2 for cache synchronization.

+--------------------------------------------------------------------------------+
|User:    ZCACH DISP ATT TPF_FS_DIR                                              |
|                                                                                |
|System:  CACH0004I 12.32.15 CACHE ATTRIBUTE DISPLAY                             |
|         NAME   TPF_FS_DIR         ,ADDR 050B9000,    CF CFLOCK2                |
|         NUMBER HASH ENTRIES  97   NUMBER ENTRIES       0                       |
|         PRIMARY KEY SIZE    256   SECONDARY KEY SIZE   4                       |
|         ENTRY SIZE          328   DATA LENGTH         32                       |
|         CAST OUT TIME        60                                                |
|         DISPLAY COMPLETE                                                       |
+--------------------------------------------------------------------------------+

The following example shows the attributes for logical record cache TPF_FC_DIR. This particular logical record cache does not use a CF for cache synchronization.

+--------------------------------------------------------------------------------+
|User:    ZCACH DISP ATT TPF_FC_DIR                                              |
|                                                                                |
|System:  CACH0004I 12.32.15 CACHE ATTRIBUTE DISPLAY                             |
|         NAME   TPF_FC_DIR         ,ADDR   050B9000                             |
|         NUMBER HASH ENTRIES  97   NUMBER ENTRIES       0                       |
|         PRIMARY KEY SIZE    256   SECONDARY KEY SIZE   4                       |
|         ENTRY SIZE          328   DATA LENGTH         32                       |
|         CAST OUT TIME        60                                                |
|         DISPLAY COMPLETE                                                       |
+--------------------------------------------------------------------------------+

The following example shows synonym chain length information for logical record cache TPF_FS_DIR.

+--------------------------------------------------------------------------------+
|User:    ZCACH DISP SYN TPF_FS_DIR                                              |
|                                                                                |
|System:  CACH0006I 12.32.15 CACHE SYNONYM DISPLAY                               |
|         NAME   TPF_FS_DIR         ,ADDR   050B9000                             |
|         HASH ENTRIES  97   LONGEST SYNONYM CHAIN 0                             |
|         HASH CHAINS WITH 0 ENTRIES 97                                          |
|         HASH CHAINS WITH 1 ENTRIES 0                                           |
|         HASH CHAINS WITH 2 ENTRIES 0                                           |
|         HASH CHAINS WITH 3 ENTRIES 0                                           |
|         HASH CHAINS WITH 4 ENTRIES 0                                           |
|         HASH CHAINS WITH 5 ENTRIES 0                                           |
|         DISPLAY COMPLETE                                                       |
+--------------------------------------------------------------------------------+

The following example shows the current data collection counters for logical record cache TPF_FS_DIR.

+--------------------------------------------------------------------------------+
|User:    ZCACH DISP CO TPF_FS_DIR                                               |
|                                                                                |
|System:  CACH0005I 12.32.15 CACHE DATA COLLECTION COUNTER DISPLAY               |
|         NAME   TPF_FS_DIR ,ADDR   093C0000                                     |
|         NUMBER ENTRIES     100     CAST OUT TIME  60                           |
|         CALLS               0      CASTOUTS        0                           |
|         UPDATES             0      INVALIDATED     0                           |
|         DUPLICATE HASH REFUSALS      0_                                        |
|         DISPLAY COMPLETE                                                       |
+--------------------------------------------------------------------------------+

The following example shows processor shared caches being enabled to use the CF for cache synchronization.

+--------------------------------------------------------------------------------+
|User:    ZCACH CF ENABLE                                                        |
|                                                                                |
|System:  CACH0019I 12.32.15 CACHE SUPPORT ENABLED TO USE CF                     |
+--------------------------------------------------------------------------------+

Related Information