What Has Your Process Done For You Lately?
A long, long time ago, PCs could only run one program at a time. Then came the
early versions of Microsoft Windows, which allowed you to run more than one
program at a time (called multitasking) by doing some clever cheating. Instead of
letting one program have full control until it was finished, it gave each program
a chunk of time in which it got control. Technically it still only ran one
program at a time, but as far as the user was concerned, it looked like the
programs were running at the same time. The problem with this system was that
sometimes programs didn't want to give up control, and the system locked up.
Windows 95, NT4, and higher provide "true" multitasking - multiple programs run
at the same time without having to cheat. Because of this, programs can split
themselves into small tasks, called processes, and have all of these processes
run at the same time. Savant does this as a way to serve HTTP requests as
efficiently as possible. Time for an example: suppose 25 people want to look at
your web site, and all 25 HTTP requests are sent at about the same time. The
simple way to handle this situation is to have Savant service the requests one
at a time, moving from the first to the last in sequential order. This is fine
if you're the first one served, but there's going to be a noticeable pause if
you're 25th in line. So instead, Savant creates 25 processes that each act like
an individual copy of Savant, and serves all 25 requests at the same time. While
complicated, this provides extremely fast and reliable web serving. The Processes
Property Sheet is the interface through which you control how Savant creates and
handles processes.
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