COFVLH03I VLF class trimming information: `Class Minimum Trimmed Age AlertAge MaxVirt` `class minimum trimmed age alertage maxvirt class minimum trimmed age alertage maxvirt`

Explanation
 This message appears in the Health Checker message
buffer if                     CHECK(IBMVLF,VLF_MAXVIRT) issues an
exception or if VERBOSE(YES)                 has been specified for
the check.  Note that classes for which                   an exception
has not been raised are only listed if VERBOSE(YES) was          
  specified and they are currently active.
 In the message text: class
The name of the class.  An asterisk (*) before the name      
             indicates that an exception was raised for this class.

minimum trimmed age
The age in seconds of the youngest object                    
             that VLF has trimmed for this class since the check last
                        ran.  An exception is raised when this age
is less than the                      current AlertAge threshold for
this class.                                       A value of "N/A"
indicates that no trimming for this class has                   occurred
since the last time that the check ran.
alertage
The AlertAge threshold in seconds for this class.            
             AlertAge may have been set via the ALERTAGE check parameter,
                    in the current COFVLFxx parmlib member, or it
may be the                         default value of 60.
maxvirt
The space setting for this class, in 4K                      
             blocks.  MaxVirt is set via the MAXVIRT parameter in
the                         current COFVLFxx member, and specifies
the maximum space                         that VLF is permitted to
use to store objects for this                           class.  The
default value of MAXVIRT is 4096 (16 Megabytes).

System action
 The system continues processing.

Operator response
 N/A

System programmer response
 An exception has been raised if the
age of the youngest trimmed object           is less than the current
AlertAge threshold.  In that situation,                 consider raising
the MAXVIRT value for the class in the current                  COFVLFxx
parmlib member to provide more room for objects in that          
      class.  If the current MAXVIRT setting is sufficient, the age
alert              threshold can be adjusted via the ALERTAGE parameter
for this class              in the COFVLFxx parmlib member or the
ALERTAGE parameter for this                check.
 If an exception
has not been raised for a specific class, it may still           be
appropriate to change the MAXVIRT setting for that class to obtain
           maximum efficiency from VLF.  While trimming is normal,
objects that             are trimmed too soon represent a lost opportunity
to improve system              performance.

Problem determination
 N/A

Module
 COFMHCVC

Source
 The Virtual Lookaside Facility
(VLF)

Reference Documentation
 For additional
information, see:                                                
 z/OS MVS Programming: Authorized Assembler Services Reference ALE-DYN.
See information about starting VLF and COFVLFxx parameters in
the z/OS MVS Initialization and Tuning Reference. 

Automation
 N/A

Routing Code
 N/A

Descriptor Code
 N/A

COFVLH03I VLF class trimming information: Class Minimum Trimmed Age AlertAge MaxVirt class minimum trimmed age alertage maxvirt class minimum trimmed age alertage maxvirt

Explanation

System action

Operator response

System programmer response

Problem determination

Module

Source

Reference Documentation

Automation

Routing Code

Descriptor Code

COFVLH03I VLF class trimming information: `Class Minimum Trimmed Age AlertAge MaxVirt` `class minimum trimmed age alertage maxvirt class minimum trimmed age alertage maxvirt`