This section contains questions for system programmers to answer when planning for the channel-attachment configuration and for Advanced Function Presentation(TM) licensed programs.
A printed page can consist of different types of text, images, overlays, and fonts. The combination of information on the page determines the time needed to prepare the data for printing. Jobs with little text and no image or graphics are processed faster than jobs with complex pages that may include scaling and image decompression.
If an application uses N-Up Page Positioning or Cut Sheet Emulation (CSE), you will be increasing the number of pages printed per minute. For example, for a printer with a maximum throughput of 229 simplex 8.5 in. forms per minute, changing the application to print 2-Up 11 in. forms increases the maximum throughput to 354 simplex pages per minute. If the application is duplex, the maximum throughput is doubled to 708 pages per minute.
Increasing the throughput increases the amount of data per minute being transferred to and processed by the system and the printer. System and channel loads may need to be reevaluated and adjusted to allow for the increased processing and transfer requirements. Increasing the number of pages per minute also intensifies processing based on page count, such as Checkpointing. Consider increasing the Check Point interval for applications using N-Up, CSE, or duplexing.
Several things affect the performance of the system and directly affect communication with the printer:
Slower technologies such as S/370 Parallel channel and Token Ring are not recommended for applications that are data intensive and require a high bandwidth. Newer technologies such as FICON channel or Gigabit Ethernet provide excellent bandwidth and room for future growth in print data.
Plan your system so that it can adjust to the change and growth of your company.
Consider the following issues while setting up your channel-attachment configuration.
The ESCON channel is the replacement for the System/370 parallel channel. It provides improvements in data rate, physical path length, cable space requirements, and overall system connectivity.
Set the missing-interrupt handler (MIH) for 13 minutes or more.
The FICON(TM) channel is the high performance replacement for the System/370 parallel channel and the ESCON channel. It provides improvements in data rate, physical path length, cable space requirements, and overall system connectivity.
Set the missing-interrupt handler (MIH) for 15 minutes or more.