[Telaneo]

HDD performance on Windows just died after some Windows 10 update. Sure, it took two minutes to boot 7 of an HDD, but once it was going, Explorer ran fine, and Firefox would run fine after that (probably cached after boot).

Same goes for day one Windows 10 (they probably didn't touch the relevant parts). I remember having to deal with a Windows 10 machine on an HDD, and it was mostly fine after it booted, but even clean installs on more recent version are just horrible. There's probably been some optimisation done which works fine on SSDs but just thrash HDDs, and HDDs as boot drives just aren't a thing anymore (within margin of error), so it didn't matter.

The fact that they've managed to throw so much bloat on top that even SSDs start struggling though, that really is something.

[ack_complete]

A major culprit is background processes that scan the drive in the background, like CompatTelRunner.exe. Works fine if you're on an SSD, but grinds an HDD to a halt. They also forgot about their own I/O prioritization API from Vista, so it also spammed I/O at Normal instead of Background priority in the early versions. Not to mention the periodic Defender scans, the Malware Removal Tool scan that runs before each major update, etc.

Similarly, Windows Update used to consume ungodly amounts of CPU time because the update system would write a multi-hundred megabyte text log and then spend forever compressing it for upload. Then they remembered their own ETL system and switched to much more efficient binary logs.

Firefox also has problems on HDD, I remember it locking up for minutes at a time doing cache maintenance until I switched permanently to SSDs.

[fuzzfactor]

With write-amplification, SSDs are being thrashed even more than HDDs would be, the SSDs just accomplish it quicker :\

Much worse than it was only a year ago.