Windows 10: Why is Windows defragging my SSD?

I started my PC last night and got a phone call so I left it unattended for about 10 minutes. When I got off the phone I noticed that my hard drive indicator light was solidly on. I have never seen that ever, even during/after Windows Updates. I left it alone until it finished whatever it was doing which took at least 5 minutes, I then tried to find out what was going on. I noticed that the optimize/trim command was run but that only takes a few seconds so I know that wasn't just that, also I noticed that available drive space had decreased by a few GB which I always used to notice when running defrag on a HDD and after a week or so of regular use it would go back to what it was before. I then opened the event viewer and found out that Windows had defragged my SSD. WTF? I thought this was turned off with SSDs? Event ID # 258, "the storage optimizer successfully completed defragmentation on Window C:" and also the same message with WinRE_DRV.

I did some searching on this and some say that Windows never/ and that you should never defrag a SSD and others say it does, possibly in a different way that it defrags a HDD. Can someone explain to me what exactly it was doing for at least 5 minutes? This is a new PC (3 months) with a clean install of 1607 and have installed very little software, it definitely did not need a defrag and the optimize drives windows always shows OK, has never showed that it needed optimization. It does run the trim command automatically though, every week or so.

Thanks for any help in trying to understand what it was doing.

:)

 

Defragmentation stuck at 4%

I defragmented the original (C drive. Sorry for my lack of specification.

 

Volume 17437b won't defragment; 23% fragmented

*Original Title: Volume 17437b won't defragment

Can someone tell me why a volume 17437b.... on my hard drive; 23% fragmented, won't defragment?

 

You can read more on this:
The real and complete story - Does Windows defragment your SSD? - Scott Hanselman

 

Thanks, I read that earlier and he states that "your SSD will get intelligently defragmented once a month" but doesn't really go into detail on what exactly that means. I'm new to Windows 10 and new to SSDs so I'm just trying to educate myself on this.

 

Me too. Here is my info under "Optimize Drives":




It implies that my SSD needs optimisation, both generally and concerning the Reserved Partition. This implies that something needs to be done, and by me. What should I do please?

EDIT: I have just noticed this, on the same window:



"Frequency: Weekly" is incompatible with "Needs optimisation (30 days since last run." and "Needs optimisation (217 days since last run)".

Confusing. What should I do please?

PS: My SSD has 147 GB free of 223 GB, so it has lots of free space.

 

The defrag tool really needs a name change because its now starting to confuse people who are moving to SSDs.

As far as I know the built in defrag tool makes the distinction between hard drives and solid state drives. If it detects an SSD it will send the TRIM command instead of defragging it. You should notice the button text change from defrag to optimize when you click on your various drives.

At least I hope that's the case because I use the defrag tool once a week on my 3 SSDs to "optimize" them.

 

The article linked in post #2 is well worth a read.
This says that Windows 10 does indeed distinguish SSDs from spinny drives, but in some circumstances it will do actual defragmentation of an SSD, and it's deliberate behaviour.

 

Thanks David I usually disable the scheduler and run it manually once in a while.

 

I know at least with earlier SSDs defragmentation was a really bad idea because it would signifigantly reduce the life of an SSD by hitting it with a lot of write cycles. I would assume that is still at least partly true, even though SSDs now are much more substantial in terms of write cycles. If this remains true, isnt this "intelligent defrag" that Windows does still a really bad thing for SSDs?

 

I've read a lot of articles and threads on this and they all reference this one guy's blog post who works/worked at Microsoft and he's not in the storage division or really knows anything about storage, also this was posted over two years ago. Not one other person, article or employee at Microsoft has ever stated something similar (to my knowledge) and have always stated that Windows doesn't defragment SSDs, full stop. I now have first hand knowledge that it does. This is the one guy I've seen that actually has a clue: Why Windows 10, 8.1 and 8 defragment your SSD and how you can avoid this – Вадим Стеркин . Notice the tweet near the bottom that states " I just talked to that team. Bad message but no actual defragging happens." Yup, the same guy that everybody is referencing to explain that defrag does happen on SSDs that ended up changing his tune. It's my belief that Windows defrags SSDs just like HDDs and this "intelligent defragging" he posted is just pure BS.

I'm not overly worried about this, seriously, but I would love to hear from somebody who can clearly explain what exactly is happening here. We're not going to find anybody from Microsoft that can/will do this, that's for sure.

 

Hi,

If you mean defragging as in a typical spinner than no, that just can't be true.
Windows 10 has no clue on how to figure out where the actual files are stored on an SSD for it can't possibly talk straight to all types of controllers.
Even if it could, there still would be no point in defragging an SSD drive since the latency is so low. Regardless of fragmented files or no fragmented files.

If you'd want to avoid excessive writes on an ssd then you'd need third party software that intercepts and caches these.
This does exist and is quiet beneficial. Especially for data center servers.

Cheers, *Wink

 

Read the article... as I understand it, it says that the benefit is because the file system itself can get so fragmented that it can't represent all the parts of each file.

 

Hi,

Sorry but that is a load of crap by people that have not a single clue about how SSD controllers work.

That said, some companies designing controllers have no clue either. Phison, do you read me ??

As mentioned before, while fragmentation is a non-issue on home systems there are ways to prevent it etc. But on home systems ??

The misconception is on their end. Just reading that stuff makes me laugh. What nonsense that is.
Want to defragment your SSD ? Be my guest. Make sure to benchmark before and after.

Cheers, *Wink

 

Ever since the beginning of magnetic storage there was Logical and physical formatting and data placement and handling, OS works on logical level for compatibility's sake while disk drive and it's controller may have other "idea". OS normally sees only logical formatting and is not directly influencing data placement. Solid state media takes that to another level and handle data on more intelligent level dynamically changing data placement, moving data around and deleting and overwriting data in cells thru garbage cleaning and load leveling. Some may be triggered by trim command on it's own or by OS.
Side effect is that an SSD or other SS media can never be completely destroyed by SW.