How to leave free space on SSD?

[Homework_grind]

I bought a new SSD which I divided into 3 partitions for logistical reasons. I know I'm supposed to leave ~20% of the SSD free to improve performance. I see 3 ways of actually leaving the space:

-Leave a portion of the SSD unpartitioned and unformatted
-Format the free space as the same file system as the 3 "real" partitions, then hide it
-Format the 3 partitions to take up the entire SSD, then leaving ~20% free on each partition

I am currently doing the 1st way, but am not sure if it is correct.

 

[USAFRet]

What make/model/size SSD?

 

[Delroy Monjo]

Don't worry about it. Caching happens in your CPU then System RAM before it ever gets to the SSD.

 

[Homework_grind]

What make/model/size SSD?

Crucial MX100 256GB

 

[mapesdhs]

Just use Minittool Partition Wizard (free edition) to create the partitions you need.

Btw, 20% is a bit much for additional spare area. 10% should be fine, and even that's
probably unnecessary these days with consumer models for normal consumer use. I just
leave part of the drive's available space completely unused (not part of any defined
partition). The SSD's fw will make use of the spare area (as it's called) automatically.


Delroy Monjo, the concept of spare area on an SSD has absolutely nothing to do with
CPU caching. It's related to how the flash cells degrade. Manually providing a portion
of unused flash allows the SSD fw to spread write ops across a greater amount of flash,
reducing the wear on individual cells in the long term. How much this matters varies
a lot depending on the SSD model, type of flash, etc. Having said that, defining a very
large spare area can affect performance on certain models for other reasons; read
product reviews for specifics on this.

Ian.

 

[USAFRet]

Overall, I wouldn't have partitioned it, and just used a folder structure to keep things separate.

But with a 256GB drive, you need to leave at least 15-20% free. So overall, don't go much above 200GB used space on that drive.
How does an SSD handle that spread among individual partitions? It probably does not care. But with multiple partitions, you the user have to do a lot more space management.

 

[mapesdhs]

15 to 20% is too much. Remember these modern SSDs already include their own degree of excess flash.
Even 10% is likely more than most modern designs require for normal consumer use. I always use 10%
on 256GB models or less. On larger models I reduce it somewhat since it's less of an issue anyway.

Ian.