IBM Mainframe Forum Index
 
Log In
 
IBM Mainframe Forum Index Mainframe: Search IBM Mainframe Forum: FAQ Register
 

Fine tuning for VSAM dataset


IBM Mainframe Forums -> JCL & VSAM
Post new topic   Reply to topic
View previous topic :: View next topic  
Author Message
Vasanthr

New User


Joined: 24 Jan 2011
Posts: 21
Location: India

PostPosted: Sat Jan 17, 2015 2:24 am
Reply with quote

Hi Everyone,

I have a IAM file with huge number of records. I get around 200k I/O EXCP in the job log for the file in the program it is used.The program uses the file in random mode.The job takes alomst 40 -60 mins a day to complete.Could you plese provide some info how to reduce this CPU time.


Below is the file definition of the file

Code:
DEFINE CLUSTER -
  (NAME(ABC.XYZ.DATASET) -
   OWNER($IAM) -
   SHAREOPTIONS(2 3) -
   VOLUMES(* * * * * * * * * *) -
   KEYS(24 0) -
   RECSZ(0625 1250) -
   FSPC(10 10) -
   CYL(2800 2800))



IAM info report:



Code:
IAM400   INNOVATION IAM INFORMATION PRINT ROUTINE -- IAMNINFO VER 9.1/01P  -- INNOVATION DATA PROCESSING   DATE-2015.012
IAM360   STEP - STEP1   DDNAME - SYS130     DATA SET MONITORED - ABC.XYZ.DATASET
IAM361   INFO REQUESTED BY PROGRAM CARDRET   FOR INPUT PROCESSING    OPENED-2015.012.21:25:13  CLOSED-2015.012.21:47:05
IAM362   IAM DATA CHARACTERISTICS -                                                             OVERRIDES IN EFFECT:
         IAM FILE FORMAT-----------=   ENHANCED    -    IAM FILE STATUS-----------=     LOADED
         LOGICAL RECORD LENGTH-----=       1250    -    CI SIZE-------------------=       8192
         KEY SIZE------------------=         24    -    KEY OFFSET----------------=          0
         TOTAL RECORDS-------------=   65655113    -    TOTAL RECORDS DELETED-----=          8
         TOTAL RECORDS UPDATED-----=       2223    -    TOTAL RECORDS INSERTED----=       1318
IAM363   IAM FILE CHARACTERISTICS -
         BLOCKING FACTOR-----------=          4    -    BLOCK SIZE----------------=      13682
         TRACKS IN USE-------------=     208806    -    VARIABLE LENGTH OVERFLOW--=        YES
         NUMBER OF EXTENTS---------=         19    -    NUMBER OF VOLUMES---------=          4
         DATASET TYPE--------------=       KSDS    -    SHARE OPTIONS-------------=          2
         NUMBER OF IAM DATA BLOCKS-=     832630    -    HIGH ALLOCATED RBN--------=     954419
         INTEGRATED OVERFLOW (CI%)-=         10    -    DASD RESERVE (CA%)--------=         10
         FILE DEFINED DATE---------=   2015.010    -    FILE DEFINED TIME---------=   21:08:31
         FILE LOADED DATE----------=   2015.010    -    FILE LOADED TIME----------=   21:15:46
         FILE UPDATE DATE----------=   2015.012    -    FILE UPDATE TIME----------=   21:25:03
IAM372   IAM EXTENDED AREA CHARACTERISTICS -
         EXT. OVERFLOW RECORDS-----=       1196    -    EXT. OVERFLOW BLOCKS------=         10
         EXTENDED BLOCKS ALLOCATED-=     119452    -    EXTENDED PE BLOCKS--------=          0
         EXTENDED BLOCKS USED------=        256    -    EXTENDED BLOCKS AVAILABLE-=     119196
IAM365   IAM EXECUTION STATISTICS -
         TOTAL STORAGE REQUIRED----=   80658432    -    PRIME INDEX(COMPRESSED)---=   11774014
         STORAGE ABOVE THE LINE----=   80654336    -    COMPRESSED DATA STRUCTURE-=        YES
         CACHE64 STORAGE (M)-------=          0    -    TURBO BUFFERING-----------=        YES
         64-BIT INDEX STORAGE (K)--=      11712    -    TOTAL JOB 64-BIT INDEX (K)=      11712
         REQUESTS PROCESSED--------=    1425101    -    REQUESTS FAILED-----------=       1098
         DISK BLOCKS READ----------=     272382    -    DISK BLOCKS WRITTEN-------=          0
         DYNAMIC BUFFER RETRIEVALS-=     145797    -    MAXIMUM BUFFERS USED------=       4904
         MINIMUM BUFFERS USED------=         64    -    MAXIMUM BUFFERS AVAILABLE-=       4904
         DYNAMIC TABLE RETRIEVALS--=          0    -    DYNAMIC TABLE RECORDS-----=          0
IAM368   SPECIFYING A BUFNO VALUE GREATER THAN  4904 MAY IMPROVE PERFORMANCE
IAM366   IAM COMMAND EXECUTION SUMMARY -
         GET RANDOM----------------=          0    -    PUT UPDATE----------------=          0
         GET SEQUENTIAL------------=     721107    -    PUT ADD-------------------=          0
         GET PREVIOUS--------------=          0    -    POINT (START BROWSE)------=     696078
         GET KGE/GENERIC-----------=          0    -    POINT KGE/GENERIC---------=       7914
         GET (SKIP SEQUENTIAL)-----=          0    -    ERASE---------------------=          0
         ENDREQ--------------------=          0    -    WRTBFR--------------------=          0
         IAM STATISTICS------------=          0    -    IAM FLUSH BUFFER----------=          0
         CLOSE---------------------=          1    -    OPEN----------------------=          1
         CLOSE TYPE=T--------------=          0    -    VERIFY--------------------=          0
         INVALID REQUESTS----------=          0    -    RECORD LENGTH CHANGES-----=          0
         SEQ CHAINED BLOCKS READ---=      45108    -    SEQ CHAINED BLOCKS WRITTEN=          0
IAM400   INNOVATION IAM INFORMATION PRINT ROUTINE -- IAMNINFO VER 9.1/01P  -- INNOVATION DATA PROCESSING   DATE-2015.012
IAM360   STEP - STEP1  DDNAME - SYS130     DATA SET MONITORED - ABC.XYZ.DATASET
IAM361   INFO REQUESTED BY PROGRAM CARDRET   FOR INPUT PROCESSING    OPENED-2015.012.21:25:13  CLOSED-2015.012.21:47:05
IAM362   IAM DATA CHARACTERISTICS -                                                             OVERRIDES IN EFFECT:
         IAM FILE FORMAT-----------=   ENHANCED    -    IAM FILE STATUS-----------=     LOADED
         LOGICAL RECORD LENGTH-----=       1250    -    CI SIZE-------------------=       8192
         KEY SIZE------------------=         24    -    KEY OFFSET----------------=          0
         TOTAL RECORDS-------------=   65655113    -    TOTAL RECORDS DELETED-----=          8
         TOTAL RECORDS UPDATED-----=       2223    -    TOTAL RECORDS INSERTED----=       1318
IAM363   IAM FILE CHARACTERISTICS -
         BLOCKING FACTOR-----------=          4    -    BLOCK SIZE----------------=      13682
         TRACKS IN USE-------------=     208806    -    VARIABLE LENGTH OVERFLOW--=        YES
         NUMBER OF EXTENTS---------=         19    -    NUMBER OF VOLUMES---------=          4
         DATASET TYPE--------------=       KSDS    -    SHARE OPTIONS-------------=          2
         NUMBER OF IAM DATA BLOCKS-=     832630    -    HIGH ALLOCATED RBN--------=     954419
         INTEGRATED OVERFLOW (CI%)-=         10    -    DASD RESERVE (CA%)--------=         10
         FILE DEFINED DATE---------=   2015.010    -    FILE DEFINED TIME---------=   21:08:31
         FILE LOADED DATE----------=   2015.010    -    FILE LOADED TIME----------=   21:15:46
         FILE UPDATE DATE----------=   2015.012    -    FILE UPDATE TIME----------=   21:25:03
IAM372   IAM EXTENDED AREA CHARACTERISTICS -
         EXT. OVERFLOW RECORDS-----=       1196    -    EXT. OVERFLOW BLOCKS------=         10
         EXTENDED BLOCKS ALLOCATED-=     119452    -    EXTENDED PE BLOCKS--------=          0
         EXTENDED BLOCKS USED------=        256    -    EXTENDED BLOCKS AVAILABLE-=     119196
IAM365   IAM EXECUTION STATISTICS -
         TOTAL STORAGE REQUIRED----=   80658432    -    PRIME INDEX(COMPRESSED)---=   11774014
         STORAGE ABOVE THE LINE----=   80654336    -    COMPRESSED DATA STRUCTURE-=        YES
         CACHE64 STORAGE (M)-------=          0    -    TURBO BUFFERING-----------=        YES
         64-BIT INDEX STORAGE (K)--=      11712    -    TOTAL JOB 64-BIT INDEX (K)=      11712
         REQUESTS PROCESSED--------=    1425101    -    REQUESTS FAILED-----------=       1098
         DISK BLOCKS READ----------=     272382    -    DISK BLOCKS WRITTEN-------=          0
         DYNAMIC BUFFER RETRIEVALS-=     145797    -    MAXIMUM BUFFERS USED------=       4904
         MINIMUM BUFFERS USED------=         64    -    MAXIMUM BUFFERS AVAILABLE-=       4904
         DYNAMIC TABLE RETRIEVALS--=          0    -    DYNAMIC TABLE RECORDS-----=          0
IAM368   SPECIFYING A BUFNO VALUE GREATER THAN  4904 MAY IMPROVE PERFORMANCE
IAM366   IAM COMMAND EXECUTION SUMMARY -
         GET RANDOM----------------=          0    -    PUT UPDATE----------------=          0
         GET SEQUENTIAL------------=     721107    -    PUT ADD-------------------=          0
         GET PREVIOUS--------------=          0    -    POINT (START BROWSE)------=     696078
         GET KGE/GENERIC-----------=          0    -    POINT KGE/GENERIC---------=       7914
         GET (SKIP SEQUENTIAL)-----=          0    -    ERASE---------------------=          0
         ENDREQ--------------------=          0    -    WRTBFR--------------------=          0
         IAM STATISTICS------------=          0    -    IAM FLUSH BUFFER----------=          0
         CLOSE---------------------=          1    -    OPEN----------------------=          1
         CLOSE TYPE=T--------------=          0    -    VERIFY--------------------=          0
         INVALID REQUESTS----------=          0    -    RECORD LENGTH CHANGES-----=          0
         SEQ CHAINED BLOCKS READ---=      45108    -    SEQ CHAINED BLOCKS WRITTEN=          0
IAM400   INNOVATION IAM INFORMATION PRINT ROUTINE -- IAMNINFO VER 9.1/01P  -- INNOVATION DATA PROCESSING   DATE-2015.012
IAM360   STEP - STEP1   DDNAME - SYS130     DATA SET MONITORED - ABC.XYZ.DATASET
IAM361   INFO REQUESTED BY PROGRAM CARDRET   FOR INPUT PROCESSING    OPENED-2015.012.21:25:13  CLOSED-2015.012.21:47:05
IAM362   IAM DATA CHARACTERISTICS -                                                             OVERRIDES IN EFFECT:
         IAM FILE FORMAT-----------=   ENHANCED    -    IAM FILE STATUS-----------=     LOADED
         LOGICAL RECORD LENGTH-----=       1250    -    CI SIZE-------------------=       8192
         KEY SIZE------------------=         24    -    KEY OFFSET----------------=          0
         TOTAL RECORDS-------------=   65655113    -    TOTAL RECORDS DELETED-----=          8
         TOTAL RECORDS UPDATED-----=       2223    -    TOTAL RECORDS INSERTED----=       1318
IAM363   IAM FILE CHARACTERISTICS -
         BLOCKING FACTOR-----------=          4    -    BLOCK SIZE----------------=      13682
         TRACKS IN USE-------------=     208806    -    VARIABLE LENGTH OVERFLOW--=        YES
         NUMBER OF EXTENTS---------=         19    -    NUMBER OF VOLUMES---------=          4
         DATASET TYPE--------------=       KSDS    -    SHARE OPTIONS-------------=          2
         NUMBER OF IAM DATA BLOCKS-=     832630    -    HIGH ALLOCATED RBN--------=     954419
         INTEGRATED OVERFLOW (CI%)-=         10    -    DASD RESERVE (CA%)--------=         10
         FILE DEFINED DATE---------=   2015.010    -    FILE DEFINED TIME---------=   21:08:31
         FILE LOADED DATE----------=   2015.010    -    FILE LOADED TIME----------=   21:15:46
         FILE UPDATE DATE----------=   2015.012    -    FILE UPDATE TIME----------=   21:25:03
IAM372   IAM EXTENDED AREA CHARACTERISTICS -
         EXT. OVERFLOW RECORDS-----=       1196    -    EXT. OVERFLOW BLOCKS------=         10
         EXTENDED BLOCKS ALLOCATED-=     119452    -    EXTENDED PE BLOCKS--------=          0
         EXTENDED BLOCKS USED------=        256    -    EXTENDED BLOCKS AVAILABLE-=     119196
IAM365   IAM EXECUTION STATISTICS -
         TOTAL STORAGE REQUIRED----=   80658432    -    PRIME INDEX(COMPRESSED)---=   11774014
         STORAGE ABOVE THE LINE----=   80654336    -    COMPRESSED DATA STRUCTURE-=        YES
         CACHE64 STORAGE (M)-------=          0    -    TURBO BUFFERING-----------=        YES
         64-BIT INDEX STORAGE (K)--=      11712    -    TOTAL JOB 64-BIT INDEX (K)=      11712
         REQUESTS PROCESSED--------=    1425101    -    REQUESTS FAILED-----------=       1098
         DISK BLOCKS READ----------=     272382    -    DISK BLOCKS WRITTEN-------=          0
         DYNAMIC BUFFER RETRIEVALS-=     145797    -    MAXIMUM BUFFERS USED------=       4904
         MINIMUM BUFFERS USED------=         64    -    MAXIMUM BUFFERS AVAILABLE-=       4904
         DYNAMIC TABLE RETRIEVALS--=          0    -    DYNAMIC TABLE RECORDS-----=          0
IAM368   SPECIFYING A BUFNO VALUE GREATER THAN  4904 MAY IMPROVE PERFORMANCE
IAM366   IAM COMMAND EXECUTION SUMMARY -
         GET RANDOM----------------=          0    -    PUT UPDATE----------------=          0
         GET SEQUENTIAL------------=     721107    -    PUT ADD-------------------=          0
         GET PREVIOUS--------------=          0    -    POINT (START BROWSE)------=     696078
         GET KGE/GENERIC-----------=          0    -    POINT KGE/GENERIC---------=       7914
         GET (SKIP SEQUENTIAL)-----=          0    -    ERASE---------------------=          0
         ENDREQ--------------------=          0    -    WRTBFR--------------------=          0
         IAM STATISTICS------------=          0    -    IAM FLUSH BUFFER----------=          0
         CLOSE---------------------=          1    -    OPEN----------------------=          1
         CLOSE TYPE=T--------------=          0    -    VERIFY--------------------=          0
         INVALID REQUESTS----------=          0    -    RECORD LENGTH CHANGES-----=          0
         SEQ CHAINED BLOCKS READ---=      45108    -    SEQ CHAINED BLOCKS WRITTEN=          0
Back to top
View user's profile Send private message
Robert Sample

Global Moderator


Joined: 06 Jun 2008
Posts: 8696
Location: Dubuque, Iowa, USA

PostPosted: Sat Jan 17, 2015 4:01 am
Reply with quote

Since this is an IAM data set and not actually a VSAM data set, you need to contact the IAM vendor and work with them on how to improve performance. For a pure VSAM data set, BLSR can help random access -- but I don't know if BLSR can even be used with an IAM data set.
Back to top
View user's profile Send private message
Bill Woodger

Moderator Emeritus


Joined: 09 Mar 2011
Posts: 7309
Location: Inside the Matrix

PostPosted: Sat Jan 17, 2015 6:16 am
Reply with quote

I'd suggest that if the program is using random, it should not. Look at the starts. Looks like skip-sequential processing. Ensure your driver-file is sorted, and don't use random. There may be other things the program is doing that it shouldn't.

I don't know IAM, but it looks like your freespace is not being utilised, but will be taking up a lot of tracks.

Robert's advice is very good.
Back to top
View user's profile Send private message
Pete Wilson

Active Member


Joined: 31 Dec 2009
Posts: 580
Location: London

PostPosted: Thu Jan 22, 2015 6:24 pm
Reply with quote

Contacting Innovation would be a good idea, they usually respond very quickly and are usually very helpful.

It looks to me that most of the processing is sequential, only very small numbers of inserts and updates. The IAM368 message might be worth pursuing. You can add IAMOVERID DD's to the JCL when processing the file and things like buffering and other performance options can be specified there.

IAM368 SPECIFYING A BUFNO VALUE GREATER THAN 4904 MAY IMPROVE PERFORMANCE
Back to top
View user's profile Send private message
View previous topic :: :: View next topic  
Post new topic   Reply to topic View Bookmarks
All times are GMT + 6 Hours
Forum Index -> JCL & VSAM

 


Similar Topics
Topic Forum Replies
No new posts Access to non cataloged VSAM file JCL & VSAM 18
No new posts FINDREP - Only first record from give... DFSORT/ICETOOL 3
No new posts Map Vols and Problem Dataset All Other Mainframe Topics 2
No new posts Allocated cylinders of a dataset DB2 12
No new posts Sort First/last record of a subset th... DFSORT/ICETOOL 7
Search our Forums:

Back to Top