A spooler is a type of utility program that is usually bundled with an operating system of some sort. Print spoolers, for example, rout printer commands to a file on a disk or in the RAM, rather than directly to the printer. The commands are only passed to the printer when the CPU is done and idle. This is because the program that provides whatever file needs to be printed can’t do anything else while the printing process runs.
Technipages Explains Spooler
A print spooler essentially fools that program into thinking a super-fast printer is connected, when in truth the output is stored in a file for the time being. As far as the program knows, the process is complete, and it can continue running normally. Then, when both printer and computer are connected and prepped, the spooler guides the printer data along to the printer, at which point the printing process actually starts and runs.
This means that the CPU-intensive part of preparing the document and printing it is ‘completed’ from the viewpoint of the program. The final step is the one that takes the most time, but needs fewer CPU resources – the actual printing of the document to physical paper. The burden of effort there is on the printer – the computer contributes almost nothing. Instead, the printer, no matter what type of printer it is, needs to process the document, select the right paper and perform the printing process.
Without a spooler to ‘interrupt’ so to speak, the program and computer would remain busy until the entire printing process is complete. For larger documents – think hundreds of pages – this would cause a huge delay and interrupt any sort of effective work process.
Common Uses of Spooler
- Spoolers can act between any sort of slow peripheral and a computer, though most commonly it is a printer.
- A spooler is a multiprogramming tool that passes commands and files between different devices and locations.
- The use of print spoolers makes the printing process more efficient by freeing up resources as early as possible.
Common Misuses of Spooler
- A spooler is a program that sends a file to the printer from the program that created it.