Should you still leave space on NVMe drive?

[Drystoner]

I own a WD Blue SN550 which has my OS installed. Currently I have about 20% free of my 1TB drive.

I'm wondering if it's still the case that there'd be any noticeable performance impact in games and programs if I let it go to say 5 to 10% of free space?

[Razorfish]

You ALWAYS leave 25% free. if it is the boot drive.
also you have to watch out for SSD cascading..., since they DO NOT map the same way a disk drive maps.
an SSD "block" is NOT a hard drive block , it is a page. and you CANNOT erase a page in an SSD, you can only erase a BLOCK which is a fixed collection of pages.

so when an SSD needs to clear space it MUST move EVERY page out of the block to another block before it can erase the Block.
If you don't have multiple blocks free, it's gonna cascade....
and if it cascades on an older SSD, then it will become useless and you may well loose everything.


A cascade is where it is in the process of moving a block . but the new block has an error, so then it needs to find ANOTHER block, which does not have enough space for all the data trying to be recovered. Generally if a block goes bad, other blocks around it also tend to degrade.

and you may say... well it's not gonna do that, but lack of knowlege is a dangerous thing....
because there is a shed load of other rules that must be followed, like you cannot write pages next to each other or allow to high a read rate in the same area due to read leveling.

[Razorfish]

Początkowo opublikowane przez Bad 💀 Motha:

On all drives, it is always best to abide by the 10-15% free space rule.

It is OK to fill up a given drive on a temporary basis, but not good to keep it filled too much for the long term.

However unlike a hdd, an ssd can still manage to properly trim the drive even when free space is very low.

Nope........
you never need to "trim" a hard drive ,because it does not need an erase cycle, "trim" is a ♥♥♥♥♥♥ fix for a broken system where the wrong format has been used on an SSD.

Trim is simply an os command that TRIES to clear unused FILE SYSTEM blocks , since an SSD CANNOT understand file systems & format data.

only the SSD controller knows HOW those "freed blocks" map to actual SSD PAGES.

and it is NOT ok to "fill up" an SSD, well not unless you like to live dangerously, all you need is Some blocks to read bad and it is game over, because you will not have enough free blocks to move existing things about.

[Bad 💀 Motha]

What I meant by that statement about HDD vs SSD is that while you could have lets say 5% free space left on any SSD, you can still force a TRIM cleanup and it will work properly. On a HDD however, you can not defrag any HDD properly and fully with file optimizations and such that helps overall file access performance, if your HDD is below approx 10-15% free space. Apps like Auslogics Disk Defrag or Piriform Defraggler will even warn you that while you could process with the disk defrag, it can't do whats needed to help performance due to free space not being enough. Due to the fact that in order to defrag and optimize any HDD type, you need a certain minimum free space so it can move files around during the whole process. SSDs you don't need to worry about any of that.

Any drive you house an OS on though, you really should not go by the Free Space % suggestions; but instead go by a certain GB of free space. In the case of Win10 or 11, you basically NEED at least 40GB of free space on the OS drive in case it ever needs to apply large-scale Windows Updates and/or OS Feature Updates; as it will need that free space to download the new build of the OS, push the current OS into "Windows.old" and then perform the install of the new OS build. After this type of update occurs and is a success, you can free up the space again by running Disk Cleanup (Run As Admin so you can see ALL entries) and then tick ALL of those boxes (except for Downloads) and click OK to remove old junk left-over from the old OS build, Windows Updates files, cache; etc.

But yes even with an SSD, I would play it safe and unless its a very short-term thing you are doing, such as filling the drive up with downloads or video captures; which when done you will then move over to another drive, that is fine. But for normal everyday usage I would try your best to abide by the Free Space % suggestions provided to us all these years by Windows OS and Disk Defrag programs. Especially true if your SSD either does not have Over-Provisioning enabled, or does not have such a feature at all. Some SSDs have this already enabled and this space of the drive is hidden to the user and OS.

For example, Corsair 240GB SSD vs many other brands offering 250GB for the same pricing. Well the difference is that the 240GB from Corsair already has over-provisioning enabled and set aside space for that internally. If I take any Samsung 250GB SSD and go and enable over-provisioning (cause its not set aside by default); in the end I'll end up with an SSD smaller then 240GB

[Bob the Boomer]

It has nothing to do with the drive you use, the issue is windows using NTFS file system and the way it behaves when near capacity.

Of course on slower hard drives you will notice (a performance drop) it more so, and much less on SSD or NvME drives.


Leave %20 free, It comes down too the file system