Transmission and compression of data
When PSF is driving TCP/IP-attached printers or SNA-attached printers that are communication-attached, PSF can compress line data to use communication lines more efficiently. You can activate line-data compression by specifying the optional Blank compression parameter in the Printer Inventory (see Blank compression) or the COMPRESS keyword in the PRINTDEV statement (see COMPRESS).
PSF itself can do line-data compression, which is activated by specifying the optional Blank compression parameter in the Printer Inventory or the COMPRESS keyword in the PRINTDEV statement.
Line-data compression might improve performance, because PSF can
compress continuous blanks and trailing blanks and can replace strings
containing more than five blanks with Repeat String presentation text
controls. Line-data compression is most likely to improve printer
throughput when the following conditions are met:
- The printer is attached with a low-speed attachment.
- Printer throughput is limited by the attachment.
- The print job contains line data. PSF does not compress print jobs containing other kinds of data.
- The line data contains a significant number of blank strings or trailing blanks containing more than five blanks.
Note: If the line data does not have these characteristics, the use
of data compression might degrade performance. For more on blank compression,
see Blank compression for line data.