SNA RJE buffer size

Each teleprocessing buffer for SNA is prefixed in storage with a request parameter list (RPL). JES2 uses the values you have specified to determine the buffer size for RJE processing. JES2:
  1. Starts with the SNABUF=(SIZE= ) parameter value (within a range of 256-3840) on the TPDEF initialization statement.
  2. Increases SIZE= value to BUFSIZE= parameter value on the SNA RMT(nnnn) initialization statement if BUFSIZE= is larger than SIZE=.
  3. Increases SIZE= to 280 bytes if SIZE= is less than 280, and the LINENUM= parameter on the NJEDEF initialization statement is greater than 0.
  4. Adds 256 (the size of the RPL prefix) to the buffer size, rounded up to a multiple of 8, and rounded down to a maximum of 4096.

You can calculate the ‘usable’ teleprocessing (TP) buffer size by subtracting the RPL prefix area. You can display this value with a $D TPDEF operator command, which results in the $HASP839 message.

Parent topic: SNA RJE considerations