WBM_MSG_INT

   WBM_MSG_INT is one of three system parameters that are available
   for managing the update traffic between a master write bitmap
   and its corresponding local write bitmaps in an OpenVMS Cluster
   system. The others are WBM_MSG_UPPER and WBM_MSG_LOWER. These
   parameters set the interval at which the frequency of sending
   messages is tested and also set an upper and lower threshold that
   determine whether the messages are grouped into one SCS message
   or are sent one by one.

   In single-message mode, WBM_MSG_INT is the time interval in
   milliseconds between assessments of the most suitable write
   bitmap message mode. In single-message mode, the writes issued by
   each remote node are, by default, sent one by one in individual
   SCS messages to the node with the master write bitmap. If
   the writes sent by a remote node reach an upper threshhold
   of messages during a specified interval, single-message mode
   switches to buffered-message mode.

   In buffered-message mode, WBM_MSG_INT is the maximum time a
   message waits before it is sent. In buffered-message mode, the
   messages are collected for a specified interval and then sent
   in one SCS message. During periods of increased message traffic,
   grouping multiple messages to send in one SCS message to the
   master write bitmap is generally more efficient than sending each
   message separately.

   The minimum value of WBM_MSG_INT is 10 milliseconds. The maximum
   value is -1, which corresponds to the maximum positive value that
   a longword can represent. The default is 10 milliseconds.

   WBM_MSG_INT is a DYNAMIC parameter.