Question: Defragmenting an SSD drive is a bad idea and Windows 7 is (should be?) smart enough not to schedule defragmentation on such drives.
However, I’ve opened up Disk Defragmenter on my system and found, to my surprise, that my SSD has indeed been defragmented… recently!
Then I checked the disks selected for the scheduled defrag (I have one SSD and one normal disk), and there the list correctly shows only the non-SSD drive.
This MSDN forum post seems to suggest that, at least on Windows 8, defragmenting an SSD drive will just cause the TRIM command to be sent to the drive, but there’s no word on what actually happens if you try to defrag an SSD drive on Windows 7 (aside from the fact that it shouldn’t happen automatically).
What happens in Windows 7 if one chooses to defrag and SSD? What could possibly have been the reason my SSD drive got been defragmented?
EDIT:
I just remembered – I’ve moved some folders (Users and ProgramData) from my SSD drive to my normal drive using junctions. This question suggests that this shouldn’t have any effects at all on the defragmentation process, but could it have an effect on the “last run” in Disk Defragmenter?
Answer: By default, Windows 7 should automatically disable its scheduled ?defragmentation but unfortunately, I ve seen too many cases where the ?built-in Disk Defragmenter was still enabled, despite the fact that an ?SSD was built-in! Users should make sure that it s disabled. Here s ?how: Go to the Start menu and click on All Programs , Accessories , ? System Tools and Disk Defragmenter .
(Quoted from the Tune-up blog).
Microsoft confirm this here:
?
Windows 7 usually detects SSD disk after this has been installed or ?connected and integrates it properly. This also includes the detection ?that some services are disabled, which would restrict the ?functionality, performance and service life of the drive. First of ?all, you should check whether the automatic defragmentation is ?disabled. This is not the case, you should disable the automatic ?deactivation for the disc manually.
From these quotes I conclude that performing a defrag will actually do what it says (otherwise the warnings would be senseless).