StickThatInYourPipeAndSmokeIt said:
On "brand new installs"? You're an idiot.
Yes. On brand new installs.
The installation process uses the file system the same as anything else.
Since the allocation process is FIRST AVAILABLE as soon as two files are
written and the first one is deleted there is a hole and fragmentation
gets started. And there are a lot of files loaded and deleted during the
installation process. The only way that the disk would not be fragmented
after an install is if the installation process specifically ran a
defrag at the end. I have never noticed this happening.
A possible allocation algorithm to minimise defragmentation is to always
allocate into the largest contiguous unused space. This minimizes the
possibility of fragmenting a new file and gives the greatest chance that
a delete will open up a larger space. This is very effective in an
environment where there is a lot of temporary files created and dropped.
Unfortunately, this is not the way Windose works.