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How much free space to leave on a HDD/SSD?
- Thread starter iMas70
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Crucial recommend the 10-15% free spacewon an SSD, and the old 15% on a platter drive is still the go.
https://forums.macrumors.com/threads/how-much-free-space-does-an-ssd-need-to-run-good.1929295/
https://forums.macrumors.com/threads/how-much-free-space-does-an-ssd-need-to-run-good.1929295/
The short, simple answer:
SSDs have the manufacture’s recommended free space built in. It’s called provisioning or over-provisioning and is controlled by the drive’s firmware. With the Samsung 850 EVO up, it’s 8% set aside for provisioning. Other, newer SSDs are running about the same.
Older SSDs have more but with garbage collection and TRIM, that much space is no longer considered necessary. This is why you’ll see a capacity of 960GB on one SSD and 1000GB on another, both rated 1T and built with 1024 (more or less). You can allow more if you disagree with the maker of the drive.
HDDs run slower as you approach capacity. 15% is the recommended free space to avoid this.
SSDs have the manufacture’s recommended free space built in. It’s called provisioning or over-provisioning and is controlled by the drive’s firmware. With the Samsung 850 EVO up, it’s 8% set aside for provisioning. Other, newer SSDs are running about the same.
Older SSDs have more but with garbage collection and TRIM, that much space is no longer considered necessary. This is why you’ll see a capacity of 960GB on one SSD and 1000GB on another, both rated 1T and built with 1024 (more or less). You can allow more if you disagree with the maker of the drive.
HDDs run slower as you approach capacity. 15% is the recommended free space to avoid this.
For a boot drive, you'd want some free space on it for things like the VM swap file, temp files for apps, etc. Mr. Halloran explained that well in the post above.
If the drive IS NOT used as a boot drive, but for data storage only, I'll guess that one can just about "fill it up" to "the max". You'd still want -some- free space available (I'd guess about 1-2% of total capacity)...
If the drive IS NOT used as a boot drive, but for data storage only, I'll guess that one can just about "fill it up" to "the max". You'd still want -some- free space available (I'd guess about 1-2% of total capacity)...