Library /sys$common/syshlp/SCACP$HELP.HLB  —  SET  VC  Qualifiers  /ECS_MAX_DELAY
       /ECS_MAX_DELAY=n
       /NOECS_MAX_DELAY

    Sets a management-specified lower bound on the maximum delay (in
    microseconds) an ECS member channel can have. The value for n can
    be any value between 0 and 3000000. /NOECS_MAX_DELAY disables a
    prior management delay setting.

    You can use this command to override the PEdriver automatically
    calculated delay thresholds to ensure that all channels with
    delays less than the value supplied for n are included in the
    VC's ECS.

    The command operates as follows: Whenever at least one tight peer
    channel has a delay of less than the management-supplied value,
    all tight peer channels with delays less than the management-
    supplied value are automatically included in the ECS. When all
    tight peer channels have delays equal to or greater than the
    management setting, the ECS membership delay thresholds are
    automatically calculated and used. The /NOECS_MAX_DELAY qualifier
    disables management control by setting the management delay value
    to zero.

    You must determine an appropriate value for your configuration by
    experimentation. An initial value of 2000 (2 ms) to 5000 (5 ms)
    is suggested.

                                 CAUTION

       By overriding the automatic delay calculations, you
       can include a channel in the ECS whose average delay is
       consistently greater than 1.5 to 2 times the average delay
       of the fastest channels. When this occurs, the overall
       VC throughput becomes the speed of the slowest ECS member
       channel.

       An extreme example is when the management delay permits a
       10 Mb/s Ethernet channel to be included with multiple 1 Gb/s
       channels. The resultant VC throughput drops to 10 Mb/s.

    Note that the SET VC/ECS_MAX_DELAY setting is not valid beyond
    the life of the system. Therefore, you might want to include SET
    VC/ECS_MAX_DELAY commands in your startup file or reissue these
    commands at the next boot.
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