StorageTek 312564001 User Manual

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DB2 Manager User Guide 
57 
 StorageTek 
Proprietary 
 
 
Purge task 
 
P(URGE) T(ASK) = (T|D|W|S)nnn 
 
The PURGE command is used to terminate a tape or disk reader task, a 
writer task or a scheduler task in the DB2 Manager control region. All 
outstanding requests in the task queue will be allowed to complete normally 
before task termination. 
The command may be abbreviated to a single 'P'. The TASK parameter may 
be abbreviated to a single 'T'. The value 'nnn' must be numeric and should be 
preceded by the character ‘T’ for tape reader tasks, ‘D’ for disk reader tasks, 
‘W’ for writer tasks and ‘S’ for scheduler tasks.  If this character is omitted, a 
default value of ‘T’ will be used.  The task identifier entered here must 
correspond to a valid reader task number, as displayed by the status 
summary command. 
For waiting tasks (status = WAIT), the purge request will be executed 
immediately. The identified task will be terminated, and will no longer be 
available for object recall processing. It will appear with a type of TERM in 
subsequent status display requests. Any tape allocation held by a purged 
tape reader or writer task will be released - this will cause the allocated tape 
to be rewound and dismounted, and the tape drive to be freed by DB2 
Manager. 
For busy tasks (status=BUSY), a shutdown request will be added to the task 
queue. This will allow requests which were outstanding at the time the purge 
command was entered to be completed as normal. The task will then be 
terminated, and will no longer be available for processing.  It will appear with 
a type of TERM in subsequent status display requests. For tape reader tasks, 
the tape being processed by the identified task will be released, whether it 
would have normally been retained on the tape drive after use or not. 
Requests to purge a busy task for which a purge request has already been 
queued will be rejected. 
When a task is purged, the current value of the MAXTRDR, MAXDRDR, 
MAXTWTR or MAXSCHED parameters is automatically decremented by 1, 
depending on the type of task being purged. 
Example: 
 
F LCDDB2,D 
OTD20062 Maxtrdr=003 Maxdrdr=004 Maxtwtr=004 Maxsched=004 Maxqlen=100 
OTD20062 Retaintape=0001 Tapewait=0004 Objsize=00100  
OTD20062 Readtimeout=0005 Writetimeout=0005 
OTD20062 Scheduler: Queue is unlocked; Queue length=000 
OTD20063 Task T001: Status=TERM Qlen=000 
OTD20063 Task T002: Status=WAIT Qlen=000 
OTD20063 Task T003: Status=WAIT Qlen=000 
OTD20063 Task T004: Status=WAIT Qlen=000 
OTD20063 Task D001: Status=WAIT Qlen=000 
OTD20063 Task D002: Status=WAIT Qlen=000