a "fetch" is simply serving a static page. All the server does is find the file, and push it out the port. Something Unix is really good at doing. It's originally what all servers were designed to do.
When you start asking the server to use SSI, or process the file in some way -- .shtml .php3 whatever, you are asking the server to parse the file, looking for the tags, then act on those tags.
So, rather than just taking the page, and pushing it out the port, the server has to take the file, parse it, look for any tags, then work on those tags, THEN push it out the port in altered format.
This is partly why they started using .html and .shtml The server would ignore the .html files, and only parse the .shtml files. But, since most people look for .html files, many people have enabled SSI on .html as well as .shtml, so every file sent out the server is parsed. This is a really heavy drain.
Any files with .php3 is going to be even more heavily parsed.
This is why Links generates static pages. It's much less load on the CPU to serve a static page than to serve a dynamic page. Think about it this way:
You have a big can of tennis balls, and you have to toss them at the people in front of you who are practicing against the wall. If all you have to do is reach in, and toss any ball to the next person waiting, you can do it without looking at the can of balls, or really looking at anything but who wants a ball. Just reach in, and toss to whomever asked. If you had to toss only blue balls to the boys, and yellow balls to the girls, then you'd have to first think -- is it a boy or a girl -- then look for the right color ball -- then toss it. Much more work.
This is why people often run two different server configurations -- plain apache and apache mod_perl -- for instance. Any simple static request goes to the plain apache server that just tosses the ball out the port. Dynamic requests, to /perl-bin, for example, is passed to the mod_perl apache that can more efficiently handle the cgi call than plain apache -- but consumes more resources. This allows a lean, mean apache for regular requests and apache on steroids for the dynamic ones.
When you start asking the server to use SSI, or process the file in some way -- .shtml .php3 whatever, you are asking the server to parse the file, looking for the tags, then act on those tags.
So, rather than just taking the page, and pushing it out the port, the server has to take the file, parse it, look for any tags, then work on those tags, THEN push it out the port in altered format.
This is partly why they started using .html and .shtml The server would ignore the .html files, and only parse the .shtml files. But, since most people look for .html files, many people have enabled SSI on .html as well as .shtml, so every file sent out the server is parsed. This is a really heavy drain.
Any files with .php3 is going to be even more heavily parsed.
This is why Links generates static pages. It's much less load on the CPU to serve a static page than to serve a dynamic page. Think about it this way:
You have a big can of tennis balls, and you have to toss them at the people in front of you who are practicing against the wall. If all you have to do is reach in, and toss any ball to the next person waiting, you can do it without looking at the can of balls, or really looking at anything but who wants a ball. Just reach in, and toss to whomever asked. If you had to toss only blue balls to the boys, and yellow balls to the girls, then you'd have to first think -- is it a boy or a girl -- then look for the right color ball -- then toss it. Much more work.
This is why people often run two different server configurations -- plain apache and apache mod_perl -- for instance. Any simple static request goes to the plain apache server that just tosses the ball out the port. Dynamic requests, to /perl-bin, for example, is passed to the mod_perl apache that can more efficiently handle the cgi call than plain apache -- but consumes more resources. This allows a lean, mean apache for regular requests and apache on steroids for the dynamic ones.