Windows 10 suddenly wants to trim a mechanical HD

Why would you turn off optimization? I bet what you are seeing is a WMI switch value reported by the drive controller itself. You just aren't seeing the result which would be TRIM=Y for an SSD or TRIM=N for an HDD or possibly TRIM=? if the drive is a hybrid or if Optane is in play.

In any case not letting Optimization run is not a logical response. Optimization works with the disk controller to determine and run optimization. An HDD disk controller will not run SSD trim neither will an SSD disk controller run defrag. The possibility of this occurring exited many years ago but is not a concern on modern hardware.

Defrag is accomplished strictly by the operating system, not the HDD disk controller. That's why "back in the day" there were many third party programs when defragged a drive better than Windows. It is possible to run defrag on an SSD with software that does not check if the drive is an SSD or HDD.

Railtech said:

Why would you turn off optimization? I bet what you are seeing is a WMI switch value reported by the drive controller itself. You just aren't seeing the result which would be TRIM=Y for an SSD or TRIM=N for an HDD or possibly TRIM=? if the drive is a hybrid or if Optane is in play.

In any case not letting Optimization run is not a logical response. Optimization works with the disk controller to determine and run optimization. An HDD disk controller will not run SSD trim neither will an SSD disk controller run defrag. The possibility of this occurring exited many years ago but is not a concern on modern hardware.

Thank you for your response. If the WMI switch reading is indeed what's causing this, then the built in Windows 10 Defragment & Optimize program isn't either 1) not reading/polling the WMI switch, or 2) not reading it correctly.

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NavyLCDR said:

Defrag is accomplished strictly by the operating system, not the HDD disk controller. That's why "back in the day" there were many third party programs when defragged a drive better than Windows. It is possible to run defrag on an SSD with software that does not check if the drive is an SSD or HDD.

Good point. I see what you two are saying. Just for ha-ha's I'll install a 3rd party defrag to see/test if that also "trims" one of the HD partitions.

f14tomcat said:

I'm only guessing, but maybe he was referring to the garbage collection which I believe is handled by the controller. The two working in tandem for the whole process.

Not sure. I tried that Glary Utilities "Disk Speedup" and it didn't trim the HD. I suppose that for now I'll just turn off the scheduled optimization for the HD, and leave it on for the SSD. Thank you for responding, btw.

Defrag is accomplished strictly by the operating system, not the HDD disk controller. That's why "back in the day" there were many third party programs when defragged a drive better than Windows. It is possible to run defrag on an SSD with software that does not check if the drive is an SSD or HDD.

Sorry, this is not true. Disk controllers do work in conjunction with Windows Optimize on both HDD and SSD. In the case of SSD, Optimization can be either retrim or defrag. Defrag in this context however is not the old school defrag. The defrag optimization run on an SSD by Windows is an intelligent process and mostly targets filesystem metadata. Where files are fragmented, those fragments may be moved but are done so by the disk controller.

Trim or garbage collection as it relates to an SSD means that the filesystem has notified the SSD disk controller that certain cells are no longer in use. The controller marks them as free and will then write data to them again at some point. An SSD disk controller will not write to these freed cells immediately as the controller also has wear leveling in mind. On the other hand, if fragmentation of a file is high the controller may move fragments to correct that condition but the controller itself makes this decision.

Having said all that I'm certain there are still some old utilities out there that will indeed run old school defrag on an SSD drive. Anyone using such a utility should reconsider doing so. In fact, anyone using a third party optimization utility with Windows 10 should not be doing so!

Railtech said:

Sorry, this is not true. Disk controllers do work in conjunction with Windows Optimize on both HDD and SSD. In the case of SSD, Optimization can be either retrim or defrag. Defrag in this context however is not the old school defrag. The defrag optimization run on an SSD by Windows is an intelligent process and mostly targets filesystem metadata. Where files are fragmented, those fragments may be moved but are done so by the disk controller.

Trim or garbage collection as it relates to an SSD means that the filesystem has notified the SSD disk controller that certain cells are no longer in use. The controller marks them as free and will then write data to them again at some point. An SSD disk controller will not write to these freed cells immediately as the controller also has wear leveling in mind. On the other hand, if fragmentation of a file is high the controller may move fragments to correct that condition but the controller itself makes this decision.

Having said all that I'm certain there are still some old utilities out there that will indeed run old school defrag on an SSD drive. Anyone using such a utility should reconsider doing so. In fact, anyone using a third party optimization utility with Windows 10 should not be doing so!

Thank you very much for that explanation. I'm not trying to run an old school defrag on my SSD. The native Windows 10 defrag is running trim on a mechanical, spinning hard drive. When you run the defrag on any of the mechanical hard drives partitions, it runs the defrag, then jumps to the trim function. It shouldn't be doing a trim function at all.
I've reported this via the Feedback Hub.

@Sprenon

I get what you are saying. My point simply is that the Optimize Drives screen is being fed the Trim from WMI which is a response rather than an action. Have you tried viewing system performance during this supposed run of Trim via the Task Manager - Performance tab - Resource Monitor to verify that your HDD is actually doing something during this Trim? I know it shows it is running but is it really? If it is then yeah, that is something that needs to be addressed. I doubt that even if it is running there is really anything happening on the disk. I doubt that the disk controller is acting on a trim command. I think you may find that trim is running except not on your HDD but on your SSD. Sure would be interesting to know.

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@Sprenon

Giving your issue a bit more thought I am wondering if your HDD may be an SMR disk? Many drive makers are manufacturing these drives now as a way to increase capacity. These disk are a bit of a cross between an HDD with some SSD tech sprinkled on. Because of how the data is handled on these disks the controller may well make use of the Trim command. Check out the link below for details:

DiskStation Manager - Knowledge Base | Synology Inc.