Have you looked at BLSR or System Managed Buffering for this KSDS?

Mark Jacobs

On 07/19/12 08:22, Brown, Larry - RD, St. Louis, MO wrote:
Hello, we have a job that was previously using Innovation's IAM file access 
method.  The file is over 6 million records.  The job runs twice yearly and 
usually takes an hour or less to complete.  The product was removed to save on 
SW costs, and the file was converted to VSAM.  The programmer did not make any 
other changes, and the job now takes over 10 hours to complete.  I know the IAM 
product is supposed to improve performance, but can't imagine it making the 
difference between 1 and 14 hours run time.  I'm suspecting there may have been 
some JCL changes to blksize, buffers, and things like that required, but the 
programmer is unaware of any of those changes he should have made.  The job is 
only reading the file.  Does anybody have any ideas on where to start looking 
for other changes that should have been made after converting from IAM to VSAM? 
 The programmer is reviewing his source code.  Our performance support has not 
suggested anything.  Innovation claims %50-%80 reduction in processing time, so 
maybe it is just a matter of IAM vs VSAM.(?)

Here  are the JCL and VSAM definitions:

//MISC     DD DSN=ASLP00.FT.MISC,DISP=SHR,
//           AMP='BUFSP=409600,BUFND=181,BUFNI=9'

Cluster:        'ASLP00.FT.MISC'                                +       
multi-volume
Data:           'ASLP00.FT.MISC.DATA'                           Data Volume:    
PEST06  +
Index:          'ASLP00.FT.MISC.INDEX'                          Index Volume:   
PEST06  +
Data Component Information:                       Current Allocation Options:
  Device type:               3390                            Load option:       
       SPEED
  Organization:                    KSDS          EXT-ADDR             Write 
check:                   NO
  KSDS key length:                   27                      Buffer space:      
    10752
  KSDS key location:                  1                      Erase on delete:   
             NO
  Average record size:               80                      Imbedded index:    
             NO
  Maximum record size:             4084                      Replicated index:  
             NO
Allocated Space:          Unit    Primary  Secondary        Reuse option:       
          YES
  Data:          CYLINDERS             2000            2000          Share 
option:                  2-3
  Index:         CYLINDERS              300              30          Spanned 
records:               NO
Dataset Date Information:                                Key ranges present:    
    NO
CLUSTER   - ASLP00.FT.MISC                                      Storage:        
        PESTBU
                                                                 Data:          
         X4GB
                                                                 Management:    
 MGTPSF
                                                                 Owner ID:
  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Current Allocations in Tracks:            Current Utilization in Tracks:
  Allocated space:               240000          Used data space:        198827 
 (        83     %)
  Allocated extents:                   2                 Used extents:          
     2   (       100     %)
  Allocation type:                 UNIQUE                Prime records:         
         6,770,095
KSDS Index Allocation in Tracks:                Deleted records:              
3134
  Allocated space:               4500            Inserted records:             
8700
  Number of records:            14795            Updated records:            
706460
- - - - - - - - - - - Current Reorganization Information - - - - - - - - - - -
Data - Control Area Information:          Control Interval Information:
  Physical record size:               4096               Size-data:        4096 
 Index:     2560

Thanks,

Larry Brown








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--
Mark Jacobs
Time Customer Service
Tampa, FL
----

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fine, and you think they're probably lying to make you feel better?
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