Enthusiast Transforms QLC SSD Into SLC With Drastic Endurance and Performance Increase

[Shrek]

No, SSDs dont work like HDDs, the sectors are not hard mapped. Data will get moved for wear levelling purposes, and pSLC is also usually dynamically sized so shrinks as the drive fills up.

By only partitioning one quarter it never fills up beyond a quarter.

 

[Wirko]

Data will get moved for wear levelling purposes

Yes, and also to make more free space. A SSD will make free space as soon as possible (when it's idle) and not wait until you send it new gigabytes to be stored.

 

[GabrielLP14]

Curious; is this only for SATA or would it work on an NVMe drive as well?

That could have some serious performance benefits on some of the PCIe 4.0 drives that aren't really strong on IOPS.

any Silicon Motion Sata based SSDs will work, some NAND Flash Dies mgiht not work though, BICS sometimes doesnt, but just some models.
NVMe are a totally different way to do it. I`m still finding a way

Shame, as MLC or TLC mode would probably be optimal outcome.

The main issue with the video's findings is the native mode of drive had SLC cache at almost half of the new capacity. If the default cache was something like 5 gigs, then it would be worth more consideration.

However if I remember right this firmware tool can change pSLC cache size? So e.g. could boost it to 120 gigs.


They wont stop at QLC, or at least they wont stop trying.

We have an idea of how low they will allow things to go to get that profitable density, when as an example Samsung released their planar TLC drives, which ended up needing emergency firmware fixes to keep them in a adequate operational state.

The MPTools by default doesnt allow to change the pSLC Cache size but i know how to. I will do a video showing different SLC Cache sizes and their respective performance alongside testing Static only x dynamic only x hybrid

Great work, but isn't it enough to make one parition a quarter the size and leave the rest unpartitioned; then the drive will never be more than a quarter filled and run in SLC mode.

doesnt work like that, as soon as the SSD fill up it will drop speeds

 

[Shrek]

My whole point, it will not fill up to the point of needing to abandon SLC

 

[GabrielLP14]

My whole point, it will not fill up to the point of needing to abandon SLC

it will trust me

 

[Shrek]

How?

I leave 3/4 unformatted.

 

[GabrielLP14]

How?

I leave 3/4 unformatted.

the default Cache size is way smaller than 1/4th. THe SLC Cache of that BX500 was 45GB

 

[Shrek]

The cache is not dynamical? Just trying to learn here.

Switching between SLC and TLC | TechPowerUp Forums
"Recent advances in Micron NAND technology enable the SSD firmware to achieve acceleration through on-the-fly mode switching between SLC and TLC modes to create a high-speed SLC pool that changes in size and location with usage conditions."

So I keep my TLC drive less than 1/3rd full

 

[GabrielLP14]

The cache is not dynamical? Just trying to learn here.

it's Dynamic. Crucial has it's own design as they call DWA (Dynamic Write Acceleration)

 

[chrcoluk]

My whole point, it will not fill up to the point of needing to abandon SLC

Sorry I misread when you said leaving rest unused, but the drive will still move read centric data to QLC.

The firmware is designed to have as much pSLC as possible as unallocated so its ready to be used for new writes.

 

[Shrek]

Yeah, i was actually thinking of making one like this but bigger capacity and sending to Wizzard so he can test, make a custom package and ship with TPU own logo and name, like "SSD Techpowerup 512GB pSLC", that would be cool right?

Beyond cool... a small solid state drive suited for boot use is a great idea.

 

[LabRat 891]

Beyond cool... a small solid state drive suited for boot use is a great idea.

Anything >118GB and less than $60 out of pocket would be a value. (Esp. On legacy machines with SATA SSD support only)
Otherwise, mightaswell buy a P1600X.

Which, is seemingly do-able.
A 512GB QLC in forced pSLC mode would be ~128GB. Seen those for $60 or less, regularly.

 

[Shrek]

Can the modified drive still be firmware updated (and still hold the configuration)?

 

[GabrielLP14]

Anything >118GB and less than $60 out of pocket would be a value. (Esp. On legacy machines with SATA SSD support only)
Otherwise, mightaswell buy a P1600X.

Which, is seemingly do-able.
A 512GB QLC in forced pSLC mode would be ~128GB. Seen those for $60 or less, regularly.

i mean, like getting a 2TB QLC and making 512GB

 

[Shrek]

Would it be cheaper to use a TLC drive?

 

[GabrielLP14]

I would prefer using a TLC drive, problem is finding a TLC drive at 2TB that i can find a compatible MPTools

Would it be cheaper to use a TLC drive?

 

[Shrek]

I got a second hand Micron 1100 2TB SATA SSD for $45

 

[LabRat 891]

i mean, like getting a 2TB QLC and making 512GB

That would be 'ideal', being many larger capacity SSDs also have larger DRAM cache vs. smaller capacity.

Would it be cheaper to use a TLC drive?

Well, yes...You could just use a TLC drive, as-is, instead*. For modding, QLC drives are almost always less expensive/GB than TLC drives.

*But, the performance and endurance probably won't be competitive with pSLC-configured QLC.

The point (I'm seeing) with this mod is to to create a durable and fast 1/4-capacity drive, out of inexpensive large capacity QLC drives. (For boot, cache, slog, etc.).

 

[Shrek]

But, the performance and endurance probably won't be competitive with pSLC-configured QLC.

Why?

 

[LabRat 891]

Why?

TLC is slower than pSLC, and less enduring.

If you pSLC-modded a TLC drive, you'd be looking at 1/3'd storage still (v. 1/4 for QLC) but, the original purchase price would be higher.

-a 2TB QLC drive can be had for 'around' $100 USD.
pSLC modded, you'd have a ~512GB pSLC SSD.
~$0.195/GB

-a 2TB TLC drive (unless used) is between $140-200+.
pSLC modded, you'd have a ~666GB pSLC SSD.
$0.21-0.30+/GB


Unmodded TLC vs. pSLC-modded QLC:
The QLC->pSLC will be faster and have considerably more write endurance than the TLC drive.

pSLC-modded TLC vs. pSLC-modded QLC:
The modified QLC drive will cost less per GB.

 

[Shrek]

An easy test: Watch the speed as the drive fills up; if the speed for a QLC drive drops at a quarter capacity one knows that SLC is being abandoned.


In this W1zzard test
Acer Predator GM7000 4 TB Review - SLC Cache & Write Intensive Usage | TechPowerUp
The speed drops at almost exactly 1/3rd capacity

"Once the the SLC cache is full, the drive will start flushing SLC back to TLC, which affects write rates."

But using the whole space for SLC before moving is not true for all drives.

 

[Wirko]

But using the whole space for SLC before moving is not true for all drives.

Yes, they are very different and nothing is guaranteed by the manufacturer, so a FW update can increase or decrease the SLC cache size.

I can think of at least one downside of a large SLC cache: if you do a full rewrite, the drive will inevitably spend more time moving the cache contents to TLC/QLC cells. As a result, it will achieve lower average write speed. Look at TPU tests, also those newer than that of Acer GM7000. None of the SSDs are among the best in both categories, SLC cache size and sustained writes.

But this shouldn't affect people often. If you're doing full (or nearly full) rewrites routinely, you're doing something wrong, and probably need larger SSDs or HDDs.

 

[Shrek]

Me in learning mode: Let's say one has filled the drive in SLC mode and then stops; what does the drive now do in the background? push the whole content to QLC mode to maximize the remaining SLC cache?

I know it depends on the drive/firmware, so maybe I ask too much.

Anyhow, this is one sweet project.

 

[chrcoluk]

In my opinion is deffo a market to have drives that in the vendor tool could be put into pure pSLC mode, I suppose the question is if any of them will figure the idea out. Right now their development path just seems to be to push out premium priced faster sequential drives.

 

[Shrek]

Having a drive that I can thrash for 17 years, while it would otherwise have flaked out at 1 is a big deal.

I know that the endurance goes up by about 66.7, but the capacity drops by 1/4, so I'd argue 17 times the life.