[SOLVED] Degradation of speed in ssd after few months

[Ranjith M]

SSD NAME : SAMSUNG EVO 970 PLUS
OS:WINDOWS 10

When i first bought this ssd the copy transfer speed of a single file in file explorer is around 1.10 gbps as constant . But now after 3 months i noticed the same transfer speed is around 650 mbps as constant. I have checked the benchmark scores that is the same as new.

Is this issue is due to installation or background usage of many apps ?

 

[NightHawkRMX]

With Windows on it and more and more problems the performance in benchmarks will slow.

 

[Ranjith M]

With Windows on it and more and more problems the performance in benchmarks will slow.

No the benchmarks are good. Only the transfer speed in file explorer got reduced.

 

[Palorim12]

Multiple questions:

Do you have OP space set on the drive?
What capacity is the drive?
How full is the drive?
what's the model of your MB/laptop?
what NVME driver is installed?

 

[USAFRet]

No the benchmarks are good. Only the transfer speed in file explorer got reduced.

If benchmarks are good, then there is no problem.
Please show us what Samsung Magician reports.

Data transfer speed visualized in File Explorer could be many many things.
Copying what, to and from where?

 

[Ranjith M]

Multiple questions:

Do you have OP space set on the drive?
What capacity is the drive?
How full is the drive?
what's the model of your MB/laptop?
what NVME driver is installed?

I tried with Both OP set and unset but the results are same.
the ssd capacity is 500gb
The drive has 200 gb free
laptop model is acer predator helios 300 g3-571 77q
nvme driver ? I don't think i have installed any . I am having only samsung magician.

 

[Ranjith M]

If benchmarks are good, then there is no problem.
Please show us what Samsung Magician reports.

Data transfer speed visualized in File Explorer could be many many things.
Copying what, to and from where?

from local disk c to c:/temp
here c is the ssd.

 

[USAFRet]

from local disk c to c:/temp
here c is the ssd.

Copy/paste within the same drive?

That will show significantly slower than the benchmarks (Magician) would suggest.

 

[Ranjith M]

Copy/paste within the same drive?

That will show significantly slower than the benchmarks (Magician) would suggest.

Yes at first i could get 1.1 gbps as constant transfer speed in file explorer but it is 600 mbps slow i.e 700mbps

 

[USAFRet]

Again, a screencap of your Samsung Magician window, please.

 

[Ranjith M]

Again, a screencap of your Samsung Magician window, please.

https://ibb.co/KwBnPcH

IMG-20201221-175008

Image IMG-20201221-175008 hosted in ImgBB

ibb.co

here you go

 

[Palorim12]

https://ibb.co/KwBnPcH

IMG-20201221-175008

Image IMG-20201221-175008 hosted in ImgBB

ibb.co

here you go

It looks like the SLC cache is reaching its limit at that point....OR, the Dynamic Thermal guard could be kicking in to limit the writing depending on how hot the NVME SSD is getting, especially since its in a laptop with what i assume has little to no airflow in where he M.2 goes.

 

[Maxxify]

Post-SLC (TLC) speeds at Q1T1 (file transfer).

 

[Ranjith M]

It looks like the SLC cache is reaching its limit at that point....OR, the Dynamic Thermal guard could be kicking in to limit the writing depending on how hot the NVME SSD is getting, especially since its in a laptop with what i assume has little to no airflow in where he M.2 goes.

Sorry for the late reply. I also noted the thermal of ssd even on low temp the transfer rate remains the same.

 

[Ranjith M]

Post-SLC (TLC) speeds at Q1T1 (file transfer).

I don't know how to do that. Can you please explain ,how to do that ?

 

[Maxxify]

I don't know how to do that. Can you please explain ,how to do that ?

The 500GB 970 EVO Plus has up to 48GB of SLC, 6GB static and 36GB dynamic. When the drive is fuller the dynamic portion shrinks. Either way, when the SLC runs out you hit TLC speeds. The 500GB 970 EVO Plus's TLC speed is rated for up to 900 MB/s, however that is when tested at QD32 (queue depth 32). A straight file transfer is queue depth 1, threading 1, so tends to be a bit slower.

 

[Ranjith M]

The 500GB 970 EVO Plus has up to 48GB of SLC, 6GB static and 36GB dynamic. When the drive is fuller the dynamic portion shrinks. Either way, when the SLC runs out you hit TLC speeds. The 500GB 970 EVO Plus's TLC speed is rated for up to 900 MB/s, however that is when tested at QD32 (queue depth 32). A straight file transfer is queue depth 1, threading 1, so tends to be a bit slower.

So in easier terms, as much as ssd space is free the higher will be transfer speed right ? Is there any app to see the SLC occupancy ?

 

[Maxxify]

So in easier terms, as much as ssd space is free the higher will be transfer speed right ? Is there any app to see the SLC occupancy ?

The SLC cache will be larger if more space is available. Exactly how much depends on the controller and in fact it can even change based on historical workloads. I've covered Crucial patents utilized on the P5 for example where the SLC cache size is dynamic, dynamic SLC. A more traditional design will be roughly linear, e.g. at 50% drive usage your drive will have 6GB (static) + 18GB (50% of dynamic) = 24GB total. The transfer speed within SLC will be significantly faster. The SLC cache will empty during idle time or as needed, but it's not always immediate. There's no direct way to measure it and in fact it's a PITA for reviewers.

 

[Ranjith M]

The SLC cache will be larger if more space is available. Exactly how much depends on the controller and in fact it can even change based on historical workloads. I've covered Crucial patents utilized on the P5 for example where the SLC cache size is dynamic, dynamic SLC. A more traditional design will be roughly linear, e.g. at 50% drive usage your drive will have 6GB (static) + 18GB (50% of dynamic) = 24GB total. The transfer speed within SLC will be significantly faster. The SLC cache will empty during idle time or as needed, but it's not always immediate. There's no direct way to measure it and in fact it's a PITA for reviewers.

Really a nice explanation,well done. Do this memory occupancy affects great, in game loading times ?

 

[Maxxify]

Really a nice explanation,well done. Do this memory occupancy affects great, in game loading times ?

SLC is faster for both reads and writes, e.g. 25µs tR versus maybe 50µs tR for TLC (latency). In general this doesn't make much difference for app or game loading times since you're bottlenecked elsewhere, 4K performance is already strong enough with NVMe especially (moreso if DRAM is present). Typically boot/OS files or similar data may be kept in SLC but otherwise it's a write cache primarily. Games are of course read-heavy so if the drive is idle or not otherwise engaged in I/O the condition of the cache has no bearing. If you're doing mixed I/O or have done a lot of writes recently, the drive may be eager to perform maintenance although it attempts to do this when the drive is idle.