Question Are dramless TLC and QLC SSDs best to be avoided?

[cbn]

I hope that OEM isn't planning on selling that in the EU. Here warranty is mandated for two years.

Of course, they might like replacing SSDs for free...

I believe the article linked below is where that original reference came from:

https://www.tomshardware.com/reviews/hyundai-sapphire-ssd,4948.html

At Computex 2016, a flash controller manufacturer warned us about DRAMless SSDs shipping with low-endurance planar TLC NAND. 1xnm planar NAND has far less endurance than 3D NAND. The vendor told us that some of the new NAND only has 100 P/E cycles.

Since they are designed for low cost OEM systems they just have to survive the warranty cycle. In many cases that is one year.

 

[whm1974]

Good reason to avoid El Cheapo hardware.

 

[cbn]

Description of different grades of NAND in the link below:

https://www.spectek.com/docs/SpectekNANDBuyersGuide.pdf

So -AF is one of the grades of NAND that gets used for both low cost USB and SD card as well as Aggressive low cost client SSD. (I actually didn't know such a grade existed for SSD)

-AF grade is either speed optimized or density optimized (ie, if running at full speed it cannot use the full capacity of the die and if used at full capacity it cannot run at full speed). However, it says nothing about endurance being affected and it does have a warranty. Therefore my suspision/guess is that 100 P/E planar TLC (if coming from Spectek) would be -AR grade and below.

P.S. With IMFT 1024Gb 3D QLC NAND yields low, I wonder how much -AF grade 1024Gb 3D QLC they have? And how would this -AF grade 1024Gb 3D QLC perform as 512Gb MLC for SATA and NVMe? How is 4K QD1 read affected in various configurations?

 

[cbn]

Phison has a new dram-less SATA controller coming out----> https://forums.anandtech.com/threads/list-of-dram-less-ssd-controllers.2440567/page-3#post-39726385

Very excited when I saw this!

4th Gen ECC? 64MB SRAM?

(That would be sweet. I can only hope)

 

[VirtualLarry]

Crucial BX500 120GB SATA6G 2.5" SSD benchmark.

 

[cbn]

Glad to see 4K QD1 doing well.

Virtual Larry, how does it compare subjectively to your CS900?

P.S. Some information here on how memory size affects 4K QD1 read based on working set size:

https://www.anandtech.com/show/12819/the-toshiba-rc100-ssd-review/2

The Toshiba RC100 requests a block of 38 MB of host DRAM from the operating system. The OS could provide more or less than the drive's preferred amount, and if the RC100 gets less than 10MB it will give up on trying to use HMB at all.

So I speculate based on that example for RC100 that dram-less SATA SSDs will slow down a bit if data working size to SRAM ratio becomes larger than .5GB to 1GB DATA to 1MB SRAM.

 

[VirtualLarry]

Glad to see 4K QD1 doing well.

Virtual Larry, how does it compare subjectively to your CS900?

Yeah, me too. Honestly, hard to say, I haven't used a CS900 very recently. I'm pleased with both of their performance, booting, Win10 64-bit Cumulative updates, etc.

 

[hojnikb]

Description of different grades of NAND in the link below:

https://www.spectek.com/docs/SpectekNANDBuyersGuide.pdf

So -AF is one of the grades of NAND that gets used for both low cost USB and SD card as well as Aggressive low cost client SSD. (I actually didn't know such a grade existed for SSD)

-AF grade is either speed optimized or density optimized (ie, if running at full speed it cannot use the full capacity of the die and if used at full capacity it cannot run at full speed). However, it says nothing about endurance being affected and it does have a warranty. Therefore my suspision/guess is that 100 P/E planar TLC (if coming from Spectek) would be -AR grade and below.

P.S. With IMFT 1024Gb 3D QLC NAND yields low, I wonder how much -AF grade 1024Gb 3D QLC they have? And how would this -AF grade 1024Gb 3D QLC perform as 512Gb MLC for SATA and NVMe? How is 4K QD1 read affected in various configurations?

Thats a very interesting table. Also explanins a lot. Anyone that ever tweaked with flash drive MPTools will know, that these things test raw nand for bad blocks (so bins like AR can be used) and allow opting for either speed (less usable blocks due to lower ECC used) or density.

 

[Insert_Nickname]

Thats a very interesting table. Also explanins a lot. Anyone that ever tweaked with flash drive MPTools will know, that these things test raw nand for bad blocks (so bins like AR can be used) and allow opting for either speed (less usable blocks due to lower ECC used) or density.

Particularly why you should never trust cheap flashdrives and SD cards further then you can throw them. Which can be a considerable distance...

 

[hojnikb]

Particularly why you should never trust cheap flashdrives and SD cards further then you can throw them. Which can be a considerable distance...

Very true. Even if you just leave it on a table, it will lose some of its data in like a year.

 

[cbn]

Some information on the SM2259XT:

https://www.anandtech.com/show/13846/mushkin-at-ces-2019-ssds-with-96l-3d-nand-in-q2

The most interesting drive is the new entry-level Source 2 SATA SSD. We found the Mushkin Source to be a decent DRAMless SATA SSD (subject to the usual performance caveats for this product segment), and it has generally been very well priced. The Source 2 will update to Micron's 96-layer 3D TLC and the Silicon Motion SM2259XT controller. The NAND flash upgrade was sure to appear somewhere on this year's roadmaps, but Mushkin is planning to start shipping it in the second quarter of 2019, which is a little sooner than we were expecting. Toshiba kicked off the 96-layer transition last year with the XG6 but has made no move to introduce 96L flash to the retail SSD market, and the best we've heard from their partners is to expect products in the second half of 2019. Samsung announced their 96L transition plan including a 970 EVO Plus, but didn't give a detailed timeline. Intel and Micron have been pretty quiet, but based on Mushkin's plans it looks like many Micron-based drives will probably switch to 96L NAND before their Toshiba-based competitors.

The switch to the SM2259XT controller is a bit unexpected. The only drive we've encountered with the SM2259 is the Intel 545s, and we haven't run across anything else with the DRAMless -XT variant. Most vendors seem to view the SM2259(XT) as offering few advantages over the SM2258(XT), since the upgraded error correction and end to end data path protection it offers are not seen as strictly necessary for consumer drives and are more about increasing the controller's appeal for datacenter applications. Mushkin's decision to move to the SM2259XT for a low-cost drive like the Source 2 indicates that it doesn't cost any more than the SM2258XT.

So SM2259XT has more error correction compared to SM2258XT.

Comparing Crucial MX500 (SM2258) to Intel 545s (SM2259) the difference in TBW is anywhere from 44% to 60% better using the same NAND.

But I wonder if the improvement in ECC it going to be enough for 3D QLC?

 

[Billy Tallis]

But I wonder if the improvement in ECC it going to be enough for 3D QLC?

SM2259 uses the same second-generation LDPC encoder as the SM2262/2263 family, so they should be equally suitable for QLC. SM2264 and SM2270 move to their third generation LDPC encoder that is more robust specifically to meet the challenges of QLC, but is also larger and more power hungry.

 

[Rifter]

Was going to start my own thread but this one seems like a good place to ask this.

Im looking for a SSD that is going to take A LOT of abuse. It will see roughly 2-4TBW per month, sometimes even more. I want this thing to last a while(lets say 5 years min).

1TB size is fine, this is not for long term storage, obviously. This drive will be needed for a temp drive for a mix of very large(10GB+) files as well as small files(sub 20MB).

Im currently using a 3TB Toshiba enterprise 7200rpm spinner for this role and its, well, REDACTED at doing it, its had over 40TBW since October but my use case will decrease slightly moving forward. Its so bad im spending 3-4 hours twice a week defragging this thing as it hits 50%+ fragmented within 4 days. My issue with it is i just dont have the ability to both be transferring data onto it and doing something else at the same time. I really need to be able to both transfer data on and off at the same time ideally while also working with data on the drive, something a spinner just can not handle.

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[killster1]

Was going to start my own thread but this one seems like a good place to ask this.

Im looking for a SSD that is going to take A LOT of abuse. It will see roughly 2-4TBW per month, sometimes even more. I want this thing to last a while(lets say 5 years min).

1TB size is fine, this is not for long term storage, obviously. This drive will be needed for a temp drive for a mix of very large(10GB+) files as well as small files(sub 20MB).

Im currently using a 3TB Toshiba enterprise 7200rpm spinner for this role and its, well, shitty at doing it, its had over 40TBW since October but my use case will decrease slightly moving forward. Its so bad im spending 3-4 hours twice a week defragging this thing as it hits 50%+ fragmented within 4 days. My issue with it is i just dont have the ability to both be transferring data onto it and doing something else at the same time. I really need to be able to both transfer data on and off at the same time ideally while also working with data on the drive, something a spinner just can not handle.

If you think thats alot of abuse (i dont think its much) you can get a 1tb 970 pro (maybe its 320?) it has the MLC chips you are looking for.

 

[cbn]

Was going to start my own thread but this one seems like a good place to ask this.

Im looking for a SSD that is going to take A LOT of abuse. It will see roughly 2-4TBW per month, sometimes even more. I want this thing to last a while(lets say 5 years min).

1TB size is fine, this is not for long term storage, obviously. This drive will be needed for a temp drive for a mix of very large(10GB+) files as well as small files(sub 20MB).

Im currently using a 3TB Toshiba enterprise 7200rpm spinner for this role and its, well, shitty at doing it, its had over 40TBW since October but my use case will decrease slightly moving forward. Its so bad im spending 3-4 hours twice a week defragging this thing as it hits 50%+ fragmented within 4 days. My issue with it is i just dont have the ability to both be transferring data onto it and doing something else at the same time. I really need to be able to both transfer data on and off at the same time ideally while also working with data on the drive, something a spinner just can not handle.

SATA or NVMe?

4TB per month is 48TB per year and over 5 years that is 240TB. (As a a point of reference Crucial MX500 1TB has 360 TBW and the Intel 545s 1TB has 576 TBW. Samsung 860 EVO 1TB has 600 TBW)

 

[Rifter]

SATA or NVMe?

4TB per month is 48TB per year and over 5 years that is 240TB. (As a a point of reference Crucial MX500 1TB has 360 TBW and the Intel 545s 1TB has 576 TBW. Samsung 860 EVO 1TB has 600 TBW)

SATA, sorry should have mentioned that.

 

[Rifter]

If you think thats alot of abuse (i dont think its much) you can get a 1tb 970 pro (maybe its 320?) it has the MLC chips you are looking for.

Well its alot compared to my boot drive NVMe SSD which by comparison has 4TBW over 2 years lol. Thanks for the suggestion.

 

[aigomorla]

Im looking for a SSD that is going to take A LOT of abuse. It will see roughly 2-4TBW per month, sometimes even more. I want this thing to last a while(lets say 5 years min).

how on earth are you hammering a SSD with 2-4TB per month in writes?
ITs not reads that hurt the SSD, its WRITES.

In essense lets say you had a 2TB ssd, that means you write it full and then delete it and write it full on average 1-2x per month.

That doesnt sound right, unless your a photographer doing large 50meg pixil photo's, or a youtube blogger doing massive amounts of video editing.

Then my recourse to you probably isnt in getting a SSD, but a SAN, or a high end NAS on a 10GBe backbone. I can do PC -> PC transfers on a 10GBe at anywhere from 400mb/s -> 600mb/s and the most wonderful thing about it is that most NAS offer a form of redundancy so your 2-4TB of written data wont just magically go POOF unless you have a catastrophic end of the world failure happen to you.

 

[Rifter]

how on earth are you hammering a SSD with 2-4TB per month in writes?
ITs not reads that hurt the SSD, its WRITES.

In essense lets say you had a 2TB ssd, that means you write it full and then delete it and write it full on average 1-2x per month.

That doesnt sound right, unless your a photographer doing large 50meg pixil photo's, or a youtube blogger doing massive amounts of video editing.

Then my recourse to you probably isnt in getting a SSD, but a SAN, or a high end NAS on a 10GBe backbone. I can do PC -> PC transfers on a 10GBe at anywhere from 400mb/s -> 600mb/s and the most wonderful thing about it is that most NAS offer a form of redundancy so your 2-4TB of written data wont just magically go POOF unless you have a catastrophic end of the world failure happen to you.

I shoot alot of 4k content, its not small, my camera cant encode it in real time to a reasonable size, so i transfer it to PC to encode it down to a sane size and then move it onto my network storage array(have a 48TB server/NAS). I also shoot alot of regular pictures hence the smaller files, i think its this large amount of small files that is fragmenting the hell out of my poor HDD currently.

And yes upgrading my network to 10GBe has occurred to me but isnt in the cards for a few more years. A SSD to speed up my workflow will have to do for now.

 

[aigomorla]

I started my 10gbe via peer to peer.

So only one machine had access to the 10gbe, which is probably ideal for you too.
Later i upgraded that system by getting a 10gbe switch with SFP.

You can get used Mallanox SFP+ cards for dirt cheap on ebay and run DAC cable from your machine to the NAS.

That is of course if your NAS has a spare PCI-E and you can install a SFP+ card.

^ that is the video that got me into 10gbe....

I would however not follow his advice on homebrewing a 10gbe switch tho... lol....
You can get good one for under 500 dollars now if you only need 2 sfp+ ports.

 

[Rifter]

I started my 10gbe via peer to peer.

So only one machine had access to the 10gbe, which is probably ideal for you too.
Later i upgraded that system by getting a 10gbe switch with SFP.

You can get used Mallanox SFP+ cards for dirt cheap on ebay and run DAC cable from your machine to the NAS.

That is of course if your NAS has a spare PCI-E and you can install a SFP+ card.

^ that is the video that got me into 10gbe....

I would however not follow his advice on homebrewing a 10gbe switch tho... lol....
You can get good one for under 500 dollars now if you only need 2 sfp+ ports.

I will look into this, as my PC and server are only 8" apart physically.

The thing is im running a LSI HBA controller and a GPU on my server already, leaving me a single x1 PCIe3 slot available, im not sure this is enough for 10GBe.

 

[aigomorla]

1x pci-e is not enough for a 10gbe bandwith..
Do you honestly need the gpu?
Can you not run the system headless?

Maybe throw on some old hardware together and build a SAN box running Peer to Peer on that machine?

 

[Rifter]

1x pci-e is not enough for a 10gbe bandwith..
Do you honestly need the gpu?
Can you not run the system headless?

I do run it headless, the GPU is there strictly for encoding. There really is no such thing as a CPU than can do 4k to anything else encoding in real time that costs less than 2k. So i use Emby media server and a Nvdia GPU(1050Ti) to hardware decode/encode my 4k content down to whatever the end device can do in real time.

 

[cbn]

Here is an upcoming dram-less NVMe SSD from MydigitalSSD called SBXe:

https://mydigitalssd.com/pcie-m2-ngff-ssd.php

It uses Phison E8T (ie, the dram-less version of Phison E8) with TLC NAND. I think it might be planar because it doesn't say 3D TLC like SBX and BPX Pro do.

SBXe 120GB model has 80 TBW vs. SBX 128GB model with 120 TBW.

80 TBW for a 120GB model is good if it really does has planar TLC. (I am assuming the higher than expected TBW is because the E8T controller has better ECC than we see on other budget controllers like the Phison S11 found in the 15nm TLC Kingston A400 or 3D TLC Toshiba TR200). Or maybe it is the Host memory buffer factoring into the following equation:

With that noted, as pointed out in the article below host memory buffer as used by the Toshiba RC100 is only about 38MB RAM:


https://www.anandtech.com/show/12819/the-toshiba-rc100-ssd-review/2


38MB of RAM is very close to the 32MB SRAM on the Phison S11. How much RAM does the SBXe use in comparison? If around the same amount of RAM (or not much more) then I assume it is basically a difference in ECC.

 

[Insert_Nickname]

Im looking for a SSD that is going to take A LOT of abuse. It will see roughly 2-4TBW per month, sometimes even more. I want this thing to last a while(lets say 5 years min).

1TB size is fine, this is not for long term storage, obviously. This drive will be needed for a temp drive for a mix of very large(10GB+) files as well as small files(sub 20MB).

4TB per month is 48TB per year and over 5 years that is 240TB. (As a a point of reference Crucial MX500 1TB has 360 TBW and the Intel 545s 1TB has 576 TBW. Samsung 860 EVO 1TB has 600 TBW)

I'd say a regular 860EVO or Intel 545s should handle that without issues. As cbn points out, 4TB a month isn't really that much in the larger scheme of things*. I'd also see if I couldn't get a 2TB drive for the additional physical NAND, that way you'll only use 2 P/E cycles a month, since there are more physical cells present.

If you want additional security, there is really only the 860PRO available. It has a 1200TBW rating for the 1TB model (which is competitive with low-end enterprise drives), and uses MLC NAND. So should be able to withstand some abuse. But it is more expensive in the larger capacities.

That is unless you're willing/able to consider enterprise class gear.

*The spectre of write amplification might be an issue, but with mostly sequential writes shouldn't.