Question How slow would a Gen3 NVMe SSD get when it is near full ?

knowledge2121

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Sep 5, 2013
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If I fill 95% of my DRAM-less 2TB NVMe SSD with data, how slow would the drive get ?

Specs:

Sequential: Read/Write: up to 2100/1600 MB/s
IOPS: Read/Write: 220K/200K IOPS

I don't need an exact speed, I want to know how slow the drive gets roughly. just give me an estimate ....
 
As the device approaches full, it can become painfully slow.
My Daughter in law complained about her slow pc.
It took 30 minutes to boot up because the drive had so few available nand blocks to handle the writes required.
I cloned the drive to a larger ssd and the relief was complete.
95% is about the point where I think one should consider replacing with a larger ssd.
Particularly if the drive is updated actively.
 
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knowledge2121

Distinguished
Sep 5, 2013
873
7
18,995
As the device approaches full, it can become painfully slow.
My Daughter in law complained about her slow pc.
It took 30 minutes to boot up because the drive had so few available nand blocks to handle the writes required.
I cloned the drive to a larger ssd and the relief was complete.
95% is about the point where I think one should consider replacing with a larger ssd.
Particularly if the drive is updated actively.

This is not an OS drive though, I will install my games to this drive. so mostly write once, read forever kinda situation...SSDs with DRAM also suffer from this, correct ?
 
Writing is problem,Just like in HDD data is written to empty blocks first and writing speed is full but if block sector is not really empty, ie.has some data on it it has to be fully erased/deleted first and that triples number of operations. Even when data is deleted thru OS it's still on disk until it's overwritten or brought to zero state.
Problem is amplified with SSDs because they simultaneously reed or write thru 4 channels(One of reasons it's faster than HDDs which do it thru only one channel) and all writing is suspended until al target cells are in zero state. Couple of features of SSDs are GC (Garbage Collection) triggered by Trim command that brings all free (marked as deleted data) cells to zero state. Another feature of SSD is that alternates writes to free cells so it equilizes number of writes to all cells so they are used equal number of writes and that prolongs SSD's life, for that to work some" spare/empty space is needed and if that space is not adequate, it may shorten SSD's life span.