WorkManagement. Вариант защиты от переполнения таблицы задач.

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      There have been a number of cases where a program goes into a loop submitting jobs. The program consumes all available jobs on the system before an operator can effectively intervene. The problem can occur for any method used to create new jobs. Most commonly, the problems occur when using the Submit Job (SBMJOB ) command or when using the spawn()function.

      The function provided by this PTF will slow down the creation of
      new jobs. There is no effect as long as the number of jobs in
      the system is less than some threshold. The effect is small for
      any one job being created. These small delays add up. The
      maximum number of jobs is defined by the QMAXJOB system value
      which has a range of 32,000 to 485,000. The default value for
      the threshold is 90 percent of the QMAXJOB value.

      You can specify a threshold by creating a data area named
      QWTSBMDLY in library QSYS. The data area specifies a threshold,
      expressed as a percentage, where the system needs to react to
      the fact that it is approaching the QMAXJOB limit. The data
      area must be of type decimal (*DEC) and must have a length of 3
      with 0 decimal positions. Valid values are from 1 to 100,
      inclusive. If you specify a value of 100, the system will
      provide no delays and therefore no protection against hitting
      the QMAXJOB limit. If you do not create a data area or if you
      do not specify the value correctly, the system uses a value of
      90. For example, to set a threshold at 95 percent:

      CRTDTAARA DTAARA(QSYS/QWTSBMDLY)
      TYPE(*DEC) LEN(3 0)
      VALUE(95) AUT(*USE)
      TEXT(‘Theshold for delays when creating jobs.’ )

      The delays start at a half second, but increase (twice) as the
      number of jobs in the system approaches the QMAXJOB limit. The
      first increase occurs half way between the specified threshold
      and the QMAXJOB limit. The other increase occurs half way
      between the first increase and the QMAXJOB limit. By default,
      the system uses a value of 90, giving a 0.5 second delay at 90
      percent of the QMAXJOB value, a 1.0 second delay at 95 percent,
      and a 2.0 second delay at 97.5 percent. Similarly, specifying
      94 causes the system to react at 94 percent, 97 percent, and
      98.5 percent.

      If your system commonly has a very large number of jobs and if
      this is more than 90 percent of the QMAXJOB limit, you should
      create the QSYS/QWTSBMDLY data area and specify a higher
      threshold. In some cases, increasing the QMAXJOB value may be
      better, but this is not always possible. Because there is often
      some single job that submits a significant number of other jobs,
      you should specify a threshold value that is larger than what
      you would normally encounter.

      Changes to the data area are effective immediately.

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