Initial size versus Maximum size page file

Question

What is the difference between initial size versus maximum size? If i set my initial size to 512, then max to 2048 doesnt that mean 512 is allocated but the pagefile.sys can grow to 2048 depending on use? If that is true, what is the difference if i set it to 16 mb vs 512 if it expands anyways?

Answer 1

These options exist in Windows since a very long time. At that time, RAM was scarce, HDD space was scarce, too, and HDDs were real (TM) hardware that took a long time to seek a sector. That means:

• RAM was scarce: You really needed a page file, and its settings did matter.
• HDD space was scarce: You didn’t want the page file to be larger than necessary. You did not want to reserve 16 MB on your hard drive just in case you eventually might need them for swapping.
• Setting a sensibel “Initial size” allowed Windows to reserve a contiguous area on the HDD what reduced head moves and thus was crucial for the performance. (One could say, the page file was created “defragmented”.)
• Setting a large “Maximum size” allowed programs to run if RAM and initial page file size were not large enough. “Runs very slow” is somewhat better than “Does not run at all”.

This means one needed to find a sensible compromise between disk usage and performance.

Nowadays, computers have lots of RAM, huge disks, and the OS hopefully is installed on a SSD. On the other, when Windows starts to really swap out, performance gets so bad one thinks Windows completely hangs or has crashed. (Performance got even worse in the past, but in the past we were used to.) That’s why these settings are no longer that important.