Replacing Drive with SSD

Quartz quartz at
Mon Aug 31 13:41:08 UTC 2015

> Making a partition for free space is one way. Another way is to leave
> part of the drive unpartitioned. Either one just guarantees there is a
> good supply of unused blocks available to the drive.

I'm not super well versed on exactly how SSD TRIM works. How does the 
drive in question know which blocks are or aren't free, isn't that a 
function of the filesystem? For that matter, how does the drive even 
"know" which parts are or aren't partitioned, it's not like they're 
programmed to understand MBR vs GPT, etc. How does the system 
communicate to the drive firmware layer which blocks are in use? Simply 
assuming based on if or how long ago it was written to can't possibly be 
a workable solution. I'm not convinced that leaving large chunks of the 
drive 'free' has any effect on wear leveling.

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