hedwards: The amount of RAM you buy is based upon peak use, not average use.
OneFiercePuppy: But if you're using a modern O/S, your average use *should* be near peak, because your O/S should precache. Windows sure does in 7 and 8; I haven't played with 10 yet and don't know.
Besides, if you're enough of a nerd to really worry about paging, you're enough of a nerd to page into a RAM drive XD
A competently written OS should never be filling the RAM to that extent. It's a waste of RAM that could be used the next time you open a RAM intensive program. And there's a lot of them out there now that are poorly optimized and guzzle RAM just because.
We have more RAM now than we used to, but that's not a reason to bloat it up with things that we might want to use later.
hedwards: Where did you get that idea? You're supposed to have a considerable chunk of RAM free most of the time. The amount of RAM you buy is based upon peak use, not average use.
Swap isn't supposed to be used as a substitute for having enough RAM, it's supposed to be there so that you can page out programs that aren't being used at the moment, so you have plenty of RAM for what you're working on.
ET3D: Can you clarify what you're saying? I find it baffling since you seem to agree with me yet claim not to.
You say that optimally a system needs more RAM than peak use, and that is what I said. A large page file (for a dynamically allocated page file, which is the Windows default) indicates high peak use, which means that more RAM is needed, or RAM usage should be reduced (for example by moving to a less memory hungry browser, seeing if there are programs open that don't need to be, etc.).
As I also said, upgrading RAM past peak use isn't always practical, and so using Readyboost or the Windows 10 method can alleviate to an extent the performance problems that result from using more RAM than is available.
Regarding a fixed sized page file, if you're regularly using a lot more RAM than you have in your system, then a fixed size page file might provide a little more performance thanks to less fragmentation, but Readyboost or Windows 10's RAM compression (or both) would provide much more performance, so I'd suggest using one of these and leaving the page file management to Windows. (BTW, an SSD is also a good alternative.)
My point was that paging is a bit more complicated than that. You often times get a lot of paging when you have programs that have been running for a while, but haven't been closed. You might still have more than enough RAM to run all of them at once without issue, but they've been paged out pro-actively in case you need that for something you're doing right now.
All OSes do that to one extent or another as part of memory management.
I do agree though that looking at what you're doing with the RAM and how much you have is an important step here.
timppu: Does "disk usage" here mean wasting free disk space for nothing, or the system writing and reading more to the page file, than if it was doing if it was dynamically sized?
ET3D: The first. The OP has a problem of a disk too full. A fixed size page file will make that situation permanently worse, instead of just occasionally when there's high RAM usage.
In terms of performance, a fixed size page file can be better (if it's allocated when the system isn't fragmented), but as I said before, Readyboost and Windows 10 RAM compression will do a lot more for paging performance than making the page file fixed in size.
Precisely, and as the OP later stated he's only got 4gb of RAM and the disk with the pagefile is a regular HDD that's nearly full.