Question At what level of space usage does SSD performance start to degrade ?

[Mawla]

I understand that the performance of an SSD degrades when a lot of data is crammed into it. My question is:
Does the decrease in performance start with the first few GBs and worsens as more and more space is occupied?
OR does it start only after a certain threshold (percentage of space used) has been crossed?

If it's the latter, I'm guessing that the threshold will be different for different models. If so, is it possible to give some ballpark figure for a typical modern DRAM-less SSD?

Please note that, at this point, I'm more interested in a significant drop in benchmarks (say from 3000 to 2500 MB/s) rather than a more drastic decline that will be obvious even with mundane tasks.

 

[Lutfij]

It depends from SSD to SSD. I tend to keep about 50% of my SSD's empty, at most 75% full.

 

[USAFRet]

I understand that the performance of an SSD degrades when a lot of data is crammed into it. My question is:
Does the decrease in performance start with the first few GBs and worsens as more and more space is occupied?
OR does it start only after a certain threshold (percentage of space used) has been crossed?

If it's the latter, I'm guessing that the threshold will be different for different models. If so, is it possible to give some ballpark figure for a typical modern DRAM-less SSD?

Please note that, at this point, I'm more interested in a significant drop in benchmarks (say from 3000 to 2500 MB/s) rather than a more drastic decline that will be obvious even with mundane tasks.

There isn't a hard threshold, or a specific "degrade" type.

Small drives are impacted more, at the same consumed percentage level.
Performance - Read and write might be affected differently.
Longevity suffers more than read performance.
Different SSD types may be affected differently.

Generally, going past 75% or so is not recommended.

 

[geofelt]

My guess is that you may not notice anything until you get to 90% full.
When nearing full, performance can be truly awful.

 

[Bob.B]

I understand that the performance of an SSD degrades when a lot of data is crammed into it. My question is:
Does the decrease in performance start with the first few GBs and worsens as more and more space is occupied?
OR does it start only after a certain threshold (percentage of space used) has been crossed?

If it's the latter, I'm guessing that the threshold will be different for different models. If so, is it possible to give some ballpark figure for a typical modern DRAM-less SSD?

Please note that, at this point, I'm more interested in a significant drop in benchmarks (say from 3000 to 2500 MB/s) rather than a more drastic decline that will be obvious even with mundane tasks.

Using a percentage might be a little iffy 10% of 250GB is quite different than 10% of 4TB.

Then it might also depend on what your doing with the ssd.
Moving big chunks in and out.
Moving little chunks in and out.

 

[Mawla]

Thanks for the replies.
I have two reasons for asking the question. One is to gain some background knowledge and the other is for a practical application in the near future.

I'm moving to a new desktop with one 4x4 M.2 slot and one 3x4 slot. I already have a 4x4 1TB SSD and am trying to decide between 500GB and 1TB for the second slot.

I have 700GB of data (including the OS) which is expected to grow slowly - most likely by less than 50GB over the net few years, 100GB tops.

I've worked out a partitioning and storage plan according to which 48% of the 1TB drive and 52% of an additional 500GB drive will be initially used. If I go for a 1TB + 1TB combination, usage will be less than 40% each. These are with formatted capacities.

I can afford the difference in price between 500GB and 1TB for the second drive. But the larger capacity seems to be rather wasteful - unless the extra unused space will help with performance. What do you think?

 

[Lafong]

There are some differences between drives of the same brand and model, but of different capacities. Typically in favor of the larger capacity.

Those differences might not impress you at all and likely would be rarely if ever noticed in practical usage.

Generally, I'd prefer to err on the side of larger capacity...not because of those differences, but because there is some chance I will be wrong in my estimates of capacity requirements in the future.

If you buy too much capacity, probably a minor disappointment. If you buy too little, you may seriously angrify your blood....sooner or later.

Of course, you may be more price-sensitive than I am....and I'm something of a tightwad.

 

[Mawla]

Good logic. Thanks for the input.
Yes, I'm price sensitive and something of a tightwad myself., a legacy from times past when I had to count my pennies. But it's not just about money. I'm cursed with this obsession to do everything just right.

 

[USAFRet]

Thanks for the replies.
I have two reasons for asking the question. One is to gain some background knowledge and the other is for a practical application in the near future.

I'm moving to a new desktop with one 4x4 M.2 slot and one 3x4 slot. I already have a 4x4 1TB SSD and am trying to decide between 500GB and 1TB for the second slot.

I have 700GB of data (including the OS) which is expected to grow slowly - most likely by less than 50GB over the net few years, 100GB tops.

I've worked out a partitioning and storage plan according to which 48% of the 1TB drive and 52% of an additional 500GB drive will be initially used. If I go for a 1TB + 1TB combination, usage will be less than 40% each. These are with formatted capacities.

I can afford the difference in price between 500GB and 1TB for the second drive. But the larger capacity seems to be rather wasteful - unless the extra unused space will help with performance. What do you think?

Be wary of splitting a drive into multiple partitions.
It often ends up with one partition that is too small for its intended use.

As far as capacity...I would go with the 1 + 1 TB. You'll be living with these drives for several years.
But thats just me.

 

[geofelt]

Space management is simpler with a single large space.
When dealing with m.2 devices consider buying larger in the first place.
m.2 is convenient when building, but replacing or moving m.2 devices later is a pain and not as easy as 2.5" devices.