I sometimes run a defrag program, tho I'm not sure it helps an awful lot. I
generally use the built-in Windows utility.
There are a lot of other defraggers out there. I am not looking for
recommendations.
My question, - do all defraggers use the same 'logic' or 'policy' about how
& where files are positioned and arranged on the C drive ?
As mentioned, there is a common API to do the moves, but each program
uses their own logic.
The built-in defrag is OK for basic use. It doesn't give any details,
but handles the basics. 3rd party defraggers may be able to defrag more
file types, such as the page file, MFT, etc...
I think there are several free ones that may give more details. I don't
know if they are any 'better' than the built-in one.
There are well-known paid ones, such as Diskeeper, Raxco PerfectDisk,
and others.
I personally use Diskeeper, and have been using various versions of it
since NT4. DK2010 has a feature called I-FAAST that, when combined with
background defrag, rearranges sectors to optimize load speed. Every
computer is different, but it did cut the time my login prompt appears
from about 1:30 to around 0:55.
One drawback to any defragging is that it can make a mess of image
backups, mainly when you do an incremental from a base backup. Image
backups store sector locations, so defragging moves things around, and
makes it look like more has changed. A file-based backup wouldn't notice
something like that.
Defragging may also have an effect on drives/partitions where Volume
Shadow Service is active. The sector movements may trigger shadow
copies. Diskeeper has an optional defrag method that reduces that, but
that also disables I-FAAST unless you are running 16K clusters (4K
clusters are most common.)
