Sample output from the MVS Component


This is sample output from the MVS Component. Not all of the report is produced, simply because a lot of findings were made at this site and it did not seem reasonable to bore you with the entire report. Consequently, only example parts of the report are shown:

Please note that the output is narrative. The software analyzes data in your performance data base, and produces a narrative report much as would a performance analyst.

The MVS Component User Manual could be consulted for a detailed description of each finding produced by the software. A sample "rule" description from the MVS Component User Manual can be reviewed to appreciate the level of documentation provided with the MVS Component.




         MVS PERFORMANCE CONSTRAINTS ON 02OCT1996 - SYSTEM: A431
                Analyzed by Version 7.1.0 of CPExpert(tm)
          (C) Copyright 1997, Computer Management Sciences, Inc.
                               PAGE:  12



RULE MVS602: XCF MESSAGE BUFFER LENGTH MAY BE TOO SMALL


   DEFAULT: The XCF message buffers may be too small for this transport class
   Unnecessary overhead is incurred when XCF must expand the buffers to fit
   a message.  The CLASSLEN parameter was specified as 956 for this
   transport class.  You should consider increasing the message length
   for this transport class or you may wish to split the transport class,
   depending upon actual message lengths.  This finding applies to the
   following RMF measurement intervals:

                           SENT    SMALL     MESSAGES   MESSAGES    TOTAL
   MEASUREMENT INTERVAL     TO    MESSAGES   THAT FIT   TOO  BIG  MESSAGES
    8:00- 8:15,02OCT1996   CPU2         0      2,393        194      2,587
    8:00- 8:15,02OCT1996   CPU4         0     65,810        814     66,624
    8:15- 8:30,02OCT1996   CPU2         0      2,281        174      2,455
    8:30- 8:45,02OCT1996   CPU2         0      2,165        135      2,300
    8:45- 9:00,02OCT1996   CPU2         0      2,076        104      2,180
    9:00- 9:15,02OCT1996   CPU2         0      2,342        112      2,454
    9:15- 9:30,02OCT1996   CPU2         0      2,554        132      2,686


RULE MVS605: THE XCF INBOUND MESSAGE BUFFER SPACE MAY BE TOO SMALL

   The inbound message buffer space may be too small.  CPExpert noticed
   that XCF input requests were rejected because of constraints on the
   amount of input message buffer space.  An asterisk beside the buffer
   space means that the buffer space DECREASED during the reported
   measurement interval, from the preceeding measurement interval. You
   should consider increasing the amount of input message buffer space.
   This finding applies to the following measurement intervals:

                         RECEIVED   TOTAL    REJECTED      PCT     BUFFER
   MEASUREMENT INTERVAL    FROM   REQUESTS   REQUESTS   REJECTED    SPACE
   11:30-11:45,02OCT1996  CPU4         4         4       100.0      2,048K


RULE MVS651: LOCK CONTENTION WAS HIGH

   DB2DBP1_LOCK1:  The lock contention for this structure was higher than
   normal.  Higher lock contention can result in an increase in central
   processor utilization and a reduction in throughput.  If this finding
   continues to occur, you should review the alternatives listed in the
   WLM Component User Manual.  If you are unable to take action, you
   should consider increasing the LOCKCONT guidance variable, located
   in USOURCE(MVSGUIDE).  The LOCKCONT variable currently is 2%.

                                 TOTAL LOCK   REQUESTS WITH   PERCENT LOCK
   MEASUREMENT INTERVAL           REQUESTS   LOCK CONTENTION   CONTENTION
    8:00- 8:15,02OCT1996            9,740           554             6
    8:15- 8:30,02OCT1996            1,103            32             3
    8:30- 8:45,02OCT1996              693            16             2
    9:30- 9:45,02OCT1996              242            11             5
    9:45-10:00,02OCT1996              442            41             9
   10:00-10:15,02OCT1996              282            12             4
   10:15-10:30,02OCT1996              319            17             5
   12:15-12:30,02OCT1996              454            22             5



         MVS PERFORMANCE CONSTRAINTS ON 02OCT1996 - SYSTEM: A431
                Analyzed by Version 7.1.0 of CPExpert(tm)
          (C) Copyright 1997, Computer Management Sciences, Inc.
                               PAGE:  13


RULE MVS651: LOCK CONTENTION WAS HIGH

   JES2_CKPT1:  The lock contention for this structure was higher than
   normal.  Higher lock contention can result in an increase in central
   processor utilization and a reduction in throughput.  If this finding
   continues to occur, you should review the alternatives listed in the
   WLM Component User Manual.  If you are unable to take action, you
   should consider increasing the LOCKCONT guidance variable, located
   in USOURCE(MVSGUIDE).  The LOCKCONT variable currently is 2%.

                                 TOTAL LOCK   REQUESTS WITH   PERCENT LOCK
   MEASUREMENT INTERVAL           REQUESTS   LOCK CONTENTION   CONTENTION
   11:30-11:45,02OCT1996           15,183           313             2
   14:30-14:45,02OCT1996           15,036           334             2
   15:15-15:30,02OCT1996           13,934           286             2
   15:30-15:45,02OCT1996           17,326           488             3
   16:30-16:45,02OCT1996           14,910           304             2
   17:00-17:15,02OCT1996           26,769           690             3
   17:15-17:30,02OCT1996           10,397           318             3


RULE MVS652: FALSE LOCK CONTENTION WAS HIGH

   DB2DBP2_LOCK1:  The number of locks with false contention should be less
   than 0.1% of the total requests, based on IBM's guidance.  The false
   lock contention exceeded the guideline for this structure.  False lock
   contention occurs when the hashing algorithm hashes to the same lock
   table entry (hash value) for two different locks.  False lock contention
   can be reduced by increasing the size of the lock structure or selecting
   a better value for the MAXUSRS parameter in IRLMPROC.  Refer to Rule
   MVS652 in the MVS Component User Manual for additional suggestions.

                               TOTAL LOCK    FALSE LOCK     PERCENT FALSE
   MEASUREMENT INTERVAL         REQUESTS     CONTENTION    LOCK CONTENTION
   15:15-15:30,02OCT1996         12,676         2,654             21


RULE MVS660: SERVICE TIME WAS HIGH FOR SYNCHRONOUS REQUESTS

   DB2DBP1_GBP2:  The service time for this structure has exceeded the
   guidelines for synchronous requests.  Service time is accumulated from
   the time MVS issues a command for the coupling facility until the return
   from the command is recognized by MVS.  Service time is recorded for
   each structure used by each system.  You can alter the times used by
   CPExpert in making this finding by altering the SYNCSRV guidance
   variables in USOURCE(MVSGUIDE) if you are unable to make changes to
   reduce service time for the structure.

                                 TOTAL SYNC      AVERAGE SERVICE
   MEASUREMENT INTERVAL           REQUESTS     TIME (MICROSECONDS)
    8:30- 8:45,02OCT1996              13                8,030
    9:15- 9:30,02OCT1996               7                7,714
   10:15-10:30,02OCT1996              22                7,972
   16:00-16:15,02OCT1996               6                8,052


         MVS PERFORMANCE CONSTRAINTS ON 02OCT1996 - SYSTEM: A431
                Analyzed by Version 7.1.0 of CPExpert(tm)
          (C) Copyright 1997, Computer Management Sciences, Inc.
                               PAGE:  14



RULE MVS661: SERVICE TIME WAS HIGH FOR ASYNCHRONOUS REQUESTS

   DB2DBP1_GBP0:  The service time for this structure has exceeded the
   guidelines for asynchronous requests.  Service time is accumulated from
   the time MVS issues a command for the coupling facility until the return
   from the command is recognized by MVS.  Service time is recorded for
   each structure used by each system.  You can alter the times used by
   CPExpert in making this finding by altering the ASYNCSRV guidance
   variables in USOURCE(MVSGUIDE) if you are unable to make changes to
   reduce service time for the structure.

                                TOTAL  ASYNC      AVERAGE SERVICE
   MEASUREMENT INTERVAL           REQUESTS      TIME (MILLISECONDS)
   12:00-12:15,02OCT1996               1               10.82


RULE MVS661: SERVICE TIME WAS HIGH FOR ASYNCHRONOUS REQUESTS

   DB2DBP1_GBP3:  The service time for this structure has exceeded the
   guidelines for asynchronous requests.  Service time is accumulated from
   the time MVS issues a command for the coupling facility until the return
   from the command is recognized by MVS.  Service time is recorded for
   each structure used by each system.  You can alter the times used by
   CPExpert in making this finding by altering the ASYNCSRV guidance
   variables in USOURCE(MVSGUIDE) if you are unable to make changes to
   reduce service time for the structure.

                                TOTAL  ASYNC      AVERAGE SERVICE
   MEASUREMENT INTERVAL           REQUESTS      TIME (MILLISECONDS)
   12:00-12:15,02OCT1996               1               10.55



RULE MVS665: TOO MANY SYNCHRONOUS REQUESTS WERE CHANGED TO ASYNCHRONOUS

   DB2DBP2_GBP3:  The structure experienced too many requests being changed
   from synchronous to asnychronous.  If MVS determines that a synchronous
   request will be significantly delayed (perhaps because subchannels are
   busy), MVS will change the request to an asynchronous request (note that
   synchronous lock requests are not changed).  This finding could indicate
   that you need additional coupling facility links.

                                TOTAL SYNC   SYNCH REQUESTS     PERCENT
   MEASUREMENT INTERVAL          REQUESTS   CHANGED TO ASYNCH   CHANGED
    7:15- 7:30,03OCT1996            242             29           12.0

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Last updated by Don Deese on 11/10/97.