14.3.7 Deferred write processing statistical information

The following shows the statistical information about deferred write processing:

pdstedit VV-RR(Object Option) ***** DEFERRED WRITE INFORMATION *****
INPUT          :/tmp/pdstj1 [1]
OUTPUT RANGE   :**/**/** **:**:** - **/**/** **:**:** [2]
-----------------------------------------------------------------------------
HOST = test [3]
-----------------------------------------------------------------------------
EDIT TIME 2004/03/11 10:00:00 - 2004/03/11 12:00:00 [4]
[5]       [6]         [7]   [8]   [9]   [10]  [11]        [12]  [13]
SERVER    EXEC        TRG   PRSYC SYNC  DBSYC RDSYC       END   CANCL
          -----       ----- ----- ----- ----- -----       ----- -----
                      [14]  [15]  [16]        [17]  [18]
                      PMAX  PMIN  PAVG        TOTAL AVG
                      ----- ----- -----       ----- -----
sds         103          15    44    44     0     0          32    12
                          1     1     1       3.56k    35
-----------------------------------------------------------------------------
FILE KIND   LOG KIND   FIRST                 LAST                         NUM
STJ         dfw        2004/03/11 10:15:08   2004/03/11 12:33:31          103
-----------------------------------------------------------------------------

Explanation
  1. Name of input statistics unload file or name of the directory containing the input statistics unload file (maximum of 58 bytes)
  2. Output range (output start date/time to output end date/time)
  3. Name of host requesting output of deferred write processing statistical information
  4. Edit period (collection start time to collection end time)
  5. Name of server requesting output of deferred write processing statistical information
  6. Number of deferred write requests
    This is the number of times deferred write processing (delayed write processing) was executed within the specified time period.
  7. Trigger count
    This is the number of times within the specified time period that deferred write processing was requested when the percentage of updated pages in the global buffer (ratio of updated buffer sectors to the total number of buffer sectors) reached a specified value.
  8. Pre-synchronization count
    This is the number of times within the specified time period deferred write processing was requested because a specified value was reached before the synchronization point dump interval (the number of times data that was output to the system log file reached a specified value before the next synchronization point dump).
  9. Synchronization points count
    This is the number of database synchronization points that occurred (the number of times a synchronization point was set for database integrity assurance) within the specified time period.
  10. Database synchronization points count
    This is the number of processes for applying update buffers to the database at a synchronization point where synchronization point processing cannot be validated.
  11. RDAREA synchronization points count
    This is the number of processes for outputting to disk all update pages for RDAREAs.
  12. Pre-synchronization completion status (outputs count)
    This is the number of times within the specified time period all the update buffer was output to the HiRDB file before the next synchronization point dump when deferred write processing was requested because a specified value was reached before the synchronization point dump interval (the number of times data that was output to the system log file reached a specified value before the next synchronization point dump).
  13. Pre-synchronization completion status (cancellations count)
    When deferred write processing was requested because a specified value was reached before the synchronization point dump interval (the number of times data that was output to the system log file reached a specified value before the next synchronization point dump), this is the number of times within the specified time period that deferred write processing was cancelled because the utility was unable to write all the update buffer to the HiRDB file before the next synchronization point dump.
  14. Concurrency level for each disk volume (maximum value)
    This is the maximum number of disk volumes (HiRDB file system areas) on which update processing resulted from deferred write processing within the specified time period. If HiRDB file system areas are created in regular files, all such HiRDB file system areas are grouped together and counted as one.
    If the maximum and minimum values are both 1, output operations are concentrated on a particular disk volume (HiRDB file system area). If this is the case, we recommend that you create RDAREAs on which update operations occur on separate disk volumes (HiRDB file system areas). If the facility for parallel writes in deferred write processing is used, a value equal to or greater than the pd_dfw_awt_process value is recommended.
  15. Concurrency level for each disk volume (minimum value)
    This is the minimum number of disk volumes (HiRDB file system areas) on which update processing resulted from deferred write processing within the specified time period.
    If the maximum and minimum values are both 1, input and output operations are concentrated on a particular disk volume (HiRDB file system area). If this is the case, we recommend that you create one or more RDAREAs on which update operations occur on separate disk volumes (HiRDB file system areas).
  16. Concurrency level for each disk volume (average value)
    This is the average number of disk volumes (HiRDB file system areas) on which update processing resulted from deferred write processing within the specified time period.
  17. Number of output pages (total)
    This is the total number of pages output to the HiRDB file during deferred write processing (delayed write processing) within the specified time period.
  18. Number of output pages (average)
    This is the average number of pages output to the HiRDB file during deferred write processing (delayed write processing) within the specified time period.