these capacities are in bits, not bytes. The biggest one is only ~170GB. Even if these were suitable for phone use - which WD saying thumb drives and memory cards (much lower margin products) suggests is not the case - they'd only offer an incremental increase in capacity vs existing 1Tb (aka 128 GB) flash dies.
"The IC will be initially used for consumer products Western Digital sells under the SanDisk brand, so think of memory cards (e.g., high-capacity SD and microSD products), USB drives, and some other devices."
User 1: Dear me, what are those things coming out of Western Digital's nose? User 2: QLC NAND! User 1: Oh shit! There goes the endurance.
A blog about QLC was claiming that QLC will have about the same total data written endurance as TLS/ML/SLC. You're mostly just giving up cycle endurance. As long as you don't do a lot of in-place updates or use a COW style filesystem and don't delete anything, it'll be pretty much the same.
I assume it is close, but not exactly the same and isn't transparent to the end user. Most people don't concern themselves with if the data is being updated vs newly written. And most filesystems aren't optimized for this pattern. I guess it mostly depends on the SSD's wearleveing.
What exactly is "total data endurance" vs. "cycle endurance"? What you can use to define the endurance is an absolute measurement like P/E cycles. This is the one defining the cell and the technology. "Total data endurance" or most likely TBW and is always relative to the size of the whole SSD. And DWPD is equally relative since it will relate to the warranty period instead of the actual physical capability of the cells.
And without changing some other parameters of the technology, like moving from floating gate transistors to charge trap flash (more or less from planar to 3D), or making the cells a lot larger, using larger fabrication nodes, there is no theoretical way in which QLC is as reliable as TLC or MLC.
In practice it might as well be since manufacturers tend to be very conservative and understate the endurance to avoid customer backlash and lawsuits if they overstate it. I have SSDs that exceeded their declared endurance several times over. And the SSD itself might crap out even if most of the cells are still more than capable of holding charge. But if you put the cells side by side, all other things identical, QLC cannot match MLC or TLC in endurance.
My naive layman understanding is for all things being equal, TBW across SLC, MLC, TLC, and QLC are about the same, assuming ideal IO patterns. The more bits you store, the more sensitive to write amplification. When it comes to bulk storage, QLC is going to be almost exactly as reliable as SLC.
Google was also talking on this general subject. In general, they've been starting to us TLC drives in their servers because the failure rate between TLC and SLC are nearly identical in their datacenters. Their SSDs almost never "wear out". They either die to defects or get replaced as part of a normal upgrade cycle.
You really need to know your IO patterns to know if QLC will work for you. It is not a drop in replacement. Facebook is all excited about them because of their write-only bulk storage. Log file systems may get popular again.
The second paragraph is something that I can sign off on. The SSDs I've seen or heard of failing, failed before their endurance was up. Conversly, there was a large-ish test of Samsung 830 SSDs that had them write tons of data continuously and it far exceeded the specified write endurance. Often times a shutdown would result in the drive becoming unusable though, suggestion other issues at play. The first paragraph seems weird, though. SLC has many more write cycles, more than the other technologies (eMLC might come close). It doesn't compute that it should be almost identical to QLC in similar conditions. 3D QLC write endurance will be on the level of early planar NAND TLC, most likely. Which was fine. My 840 Samsung has only 35TB written over the last 5 years or so. It's doing fine. And that was my system drive with games and programs and reinstalls of Windows.
The reason reliability was the same for SLC vs MLC is that the drives either fail for other reasons or they reach EOL and are cycled out prior to either one failing. As a result you don't gain anything by going with more expensive/lower capacity SLC drives if both can outlast their expected service lifetime.
@Reflex: Was that meant as a comment to me? Because I did understand and agree with his point on the "SSDs fail before their endurance is up" point, as you just reiterated. I was and am still confused by his claim that SLC through QLC should have the same endurance, which is patently false, unless he can enlighten us with his research or show us other findings. TBW does not refer to the amount of stuff you can write to the drive before it fails (that would be along the ways of the MTBF), but to the amount of data the drive can handle (raw data, with amplification) on a cell/NAND level that the manufacturer guarantees. If you write more than the alotted amount to the NAND or the drive fails after the warranty, the manufacturer doesn't need to replace anything. If the drive fails before your warranty end or if the NAND cells go bad (read only) and you have not written more than the TBW, then you can claim warranty.
My Samsung 830 128GB, is was still humming really well and still way more than fast enough. Recently did a dropin 860 EVO for space upgrade only. Barely much faster in every usage. Those 830 are golden.
I really like the 830's as well. VERY reliable drives. I have a lot of them floating around in my various builds in my house, and in several of my servers. Another drive which is rock solid are the older Crucial M4's and MX100 series. I have several in servers here at home and they just won't die (Good thing huh?).
My first Samsung 830 128GB died on me within less then a year. Got replacement and it is still working for last 3 years. Can't complain just need to upgrade it due size.
You will get a new amoled phone/TV before it burns in. You will get a new iPhone before the battery cant maintain appropriate voltage. Maybe I have a small drive or one which is written to a lot (or both) for witch 1000 P/E just doesn't cut it. Maybe I want to use the drive for a long time. Or, the craziest idea of them all maybe when I need a bigger drive I can ADD another one instead of replacing my old one (you know since the old one didn't burn through all of its P/E cycles). This trend where you get a small price reduction for a lot lower quality is of great benefit to producing companies (Samsung already has a margin of about 75% on its memory chips) but very bad for the consumer (its already hard to find consumer MLC drives).
Is this the chant of the Planned Obsolescence Brigade?
"You will be forced to get a new iPhone once your battery no longer maintains enough voltage." "You will be forced to get a new TV before burn-in is an issue because of the use of cheap caps."
Its not about planned obsolescence its about people defending bad/worse than already available technologies. The iPhone battery thing was a device design mistake. OLED burn in is a inherent issue of the technology (thats why Samsung despite being the best at OLED and the best at TVs makes no OLED TVs). The people here defending QLC look to me like the people that say burn in is not an issue on OLED devices or that the iPhone battery thing was not a problem since the 2 year guarantee is over so you should get a new device anyway. The technology is simply worse in almost every possible way than what we already have and the only reason we have QLC is for companies to extend their already huge margins when they could instead just expand capacity (thats why I mentioned Samsungs margin on memory chips) memory makers have huge margins but they still want to halve the production cost at the cost of durability, the fact that consumers will have to buy new drives earlier is just an added bonus.
Lets use an example: Kingston SSDNow G2 240GB planar MLC - 300 TBW Kingston A1000 240GB 3D TLC - 150 TBW That looks to me like half the endurance when 3D TLC was supposed to have similar endurance to planar MLC, actualy if you look you will notice that manufacturers no longer provide TBW instead providing the more ambiguous and arbitrary MTBF (the reason I use Kingston drives as an example is because they still provide TBW) so there goes drive endurance. As for cost, memory companies already have huge margins (Samsung approaching 75%) so most of the cost of the drives is from the profit the companies make not from the cost of making the NAND (they just want spend even less which is normal for for profit companies but that doesn't mean consumers should swallow their bullshit marketing) so there goes cost. As for size that is the only somewhat good point, however size can be reduced by 33% just by going from 64L to 96L witch it did and could continue to do (dont know for how long) without sacrificing endurance, but Samsung sells 2TB single sided m2 drives so at least in the consumer space size does not seem to be a problem. But hey, that's just my limited understanding based of my amateur observations, maybe a true enthusiast like yourself could shed some light on my unfounded concerns.
Edit: the TBW should be measured in TB Also more examples: Samsung 860 EVO 250GB TBW -150 TB MTBF - 1.500k h Samsung 960 EVO 250GB TBW -100 TB MTBF - 1.500k h Notice how the endurance went down between generations (I'm assuming because of a smaller node) but MTBF remained the same? :)
with SLC->QLC transition capacity grows only linearly, while endurance fails exponentially. SLC had 100K cycles, while TLC with the same error-correction algos had only 500 cycles
it's pure math - with N bits per cell, you have only N times more capacity, but need to distinguish 2^N signal levels which, all things being equal, require to have 2^N bigger cell
That doesn't seem right. 2 bits per cell means you can store 4 pieces of info, instead of 2. At 3 bits per cell, it's 8 unique values per cell. at 4 bits per cell, it's 16 unique values. So QLC is, for the same physical size, 16x more dense.
Back in the day, you could get a X-25E 32-ish gig drive that had roughly 100,000 P/E cycles. I don't know where you can buy SLC-only devices today. Nowadays, you can get a 2-4ishTB drive with only 1000 P/E cycles (about 50x-100x-ish the size). Given the relative size of the drive, the TBW is reasonably in the same ballpark, so I would expect endurance, as per measured in bytes written, to be the same order of magnitude. Given that several studies have suggested that the biggest limiting factor in drive replacement isn't really endurance failure, but other factors, it doesn't sound to me like fancy expensive high-endurance-on-a-per-cell basis is all that important.
TBW: Micron P300 200GB planar SLC - 3.5 Petabytes Samsung 960 EVO 250GB 3D TLC - 100 Terabytes The only reason for the reduced TBW was the small capacity, bigger capacity would stack with the superior endurance of SLC.
@bcronce, I perfectly agree that the SSD has a chance to fail for multiple other resins then failing cells. As I said in my previous comment I noticed this myself, albeit on a much smaller sample than Google's.
But the fact that the SSDs might fail after the same TBW doesn't lead to the conclusion that MLC, TLC, and QLC have the same endurance but rather that SSD (as in the entire usint) tends to fail before you reach any of those limits.
A QLC cell will fail faster than a MLC all other things identical. It's physics. You can mitigate it with better error recovery algorithms, more spare space, bigger cell and manufacturing process but in the end it will still fail faster.
"Luckily" you might not notice because the rest of the SSD will give up before that. :)
They may go bigger node for sure. They are saving alot by going 96L, they may aswell lose some by going larger node, maybe still pulling ahead a little in the end. Maybe yields are also abit higher than smaller node's. On the other hand QLC had issues with P/E voltage so they might benefit from smaller node. We can just speculate, im sure they are doing very well :D
If you feel so secure about QLC, why bother to raise such a stink and further quote an as-yet unproven endurance rating (1000 P/E cycles - when 500 is the current capability of existing QLC products for sale today)? It's clear you aren't entirely secure in your opinion and feel the need to lash out at others to address your insecurities. I mean you're also the same person that didn't know in 2018 that Killer announced a switch to Intel NICs in 2016.
Isn't it true that one of the things that happened when they moved to 3D flash was that they also moved to an older, larger process node that had better endurance, and that adding more layers made up for the fact that each individual component in the layers of the chip were larger?
That was my understanding of what would happen when 3D Flash was still theoretical.
QLC is probably going to be great for those that are using their SSD for storage/ backup purpose. No matter what the manufacturers claim, QLC's endurance is going to be poor. It is typical marketing to downplay flaws. It will only be interesting if the price is right.
From what I gathered SSDs don't get along so well with being a written to, then powered off for a long time style backup device. Not sure if QLC has equal or worse issues in that use case.
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Samus - Friday, July 20, 2018 - link
512GB-1TB integrated storage for smartphones inbound.DanNeely - Friday, July 20, 2018 - link
these capacities are in bits, not bytes. The biggest one is only ~170GB. Even if these were suitable for phone use - which WD saying thumb drives and memory cards (much lower margin products) suggests is not the case - they'd only offer an incremental increase in capacity vs existing 1Tb (aka 128 GB) flash dies.deil - Friday, July 20, 2018 - link
Still that upgrade is quite soon, comparing to others which suggests they are a bit ahead of the class. Next topic: where is mine re-ram ?Tyns - Saturday, July 21, 2018 - link
And those numbers are also per die; they include more than one die per package, DanPeachNCream - Friday, July 20, 2018 - link
"The IC will be initially used for consumer products Western Digital sells under the SanDisk brand, so think of memory cards (e.g., high-capacity SD and microSD products), USB drives, and some other devices."User 1: Dear me, what are those things coming out of Western Digital's nose?
User 2: QLC NAND!
User 1: Oh shit! There goes the endurance.
bcronce - Friday, July 20, 2018 - link
A blog about QLC was claiming that QLC will have about the same total data written endurance as TLS/ML/SLC. You're mostly just giving up cycle endurance. As long as you don't do a lot of in-place updates or use a COW style filesystem and don't delete anything, it'll be pretty much the same.I assume it is close, but not exactly the same and isn't transparent to the end user. Most people don't concern themselves with if the data is being updated vs newly written. And most filesystems aren't optimized for this pattern. I guess it mostly depends on the SSD's wearleveing.
deil - Friday, July 20, 2018 - link
with spare space they can over-provision it aggressively and gain speed and easy wear level.close - Friday, July 20, 2018 - link
What exactly is "total data endurance" vs. "cycle endurance"? What you can use to define the endurance is an absolute measurement like P/E cycles. This is the one defining the cell and the technology. "Total data endurance" or most likely TBW and is always relative to the size of the whole SSD. And DWPD is equally relative since it will relate to the warranty period instead of the actual physical capability of the cells.And without changing some other parameters of the technology, like moving from floating gate transistors to charge trap flash (more or less from planar to 3D), or making the cells a lot larger, using larger fabrication nodes, there is no theoretical way in which QLC is as reliable as TLC or MLC.
In practice it might as well be since manufacturers tend to be very conservative and understate the endurance to avoid customer backlash and lawsuits if they overstate it. I have SSDs that exceeded their declared endurance several times over. And the SSD itself might crap out even if most of the cells are still more than capable of holding charge.
But if you put the cells side by side, all other things identical, QLC cannot match MLC or TLC in endurance.
bcronce - Friday, July 20, 2018 - link
My naive layman understanding is for all things being equal, TBW across SLC, MLC, TLC, and QLC are about the same, assuming ideal IO patterns. The more bits you store, the more sensitive to write amplification. When it comes to bulk storage, QLC is going to be almost exactly as reliable as SLC.Google was also talking on this general subject. In general, they've been starting to us TLC drives in their servers because the failure rate between TLC and SLC are nearly identical in their datacenters. Their SSDs almost never "wear out". They either die to defects or get replaced as part of a normal upgrade cycle.
You really need to know your IO patterns to know if QLC will work for you. It is not a drop in replacement. Facebook is all excited about them because of their write-only bulk storage. Log file systems may get popular again.
Death666Angel - Friday, July 20, 2018 - link
The second paragraph is something that I can sign off on. The SSDs I've seen or heard of failing, failed before their endurance was up. Conversly, there was a large-ish test of Samsung 830 SSDs that had them write tons of data continuously and it far exceeded the specified write endurance. Often times a shutdown would result in the drive becoming unusable though, suggestion other issues at play.The first paragraph seems weird, though. SLC has many more write cycles, more than the other technologies (eMLC might come close). It doesn't compute that it should be almost identical to QLC in similar conditions.
3D QLC write endurance will be on the level of early planar NAND TLC, most likely. Which was fine. My 840 Samsung has only 35TB written over the last 5 years or so. It's doing fine. And that was my system drive with games and programs and reinstalls of Windows.
Reflex - Friday, July 20, 2018 - link
The reason reliability was the same for SLC vs MLC is that the drives either fail for other reasons or they reach EOL and are cycled out prior to either one failing. As a result you don't gain anything by going with more expensive/lower capacity SLC drives if both can outlast their expected service lifetime.Death666Angel - Saturday, July 21, 2018 - link
@Reflex: Was that meant as a comment to me? Because I did understand and agree with his point on the "SSDs fail before their endurance is up" point, as you just reiterated. I was and am still confused by his claim that SLC through QLC should have the same endurance, which is patently false, unless he can enlighten us with his research or show us other findings.TBW does not refer to the amount of stuff you can write to the drive before it fails (that would be along the ways of the MTBF), but to the amount of data the drive can handle (raw data, with amplification) on a cell/NAND level that the manufacturer guarantees. If you write more than the alotted amount to the NAND or the drive fails after the warranty, the manufacturer doesn't need to replace anything. If the drive fails before your warranty end or if the NAND cells go bad (read only) and you have not written more than the TBW, then you can claim warranty.
Byte - Friday, July 20, 2018 - link
My Samsung 830 128GB, is was still humming really well and still way more than fast enough. Recently did a dropin 860 EVO for space upgrade only. Barely much faster in every usage. Those 830 are golden.bill.rookard - Saturday, July 21, 2018 - link
I really like the 830's as well. VERY reliable drives. I have a lot of them floating around in my various builds in my house, and in several of my servers. Another drive which is rock solid are the older Crucial M4's and MX100 series. I have several in servers here at home and they just won't die (Good thing huh?).milkod2001 - Monday, July 23, 2018 - link
My first Samsung 830 128GB died on me within less then a year. Got replacement and it is still working for last 3 years. Can't complain just need to upgrade it due size.porcupineLTD - Saturday, July 21, 2018 - link
planar SLC aprox 60-100.000 P/E cycles3D QLC aprox 1000 P/E cycles
Did I miss some major breakthrough?
melgross - Saturday, July 21, 2018 - link
You missed the fact that, in practice, it doesn’t matter much. You’ll get a bigger drive before these die from writesporcupineLTD - Saturday, July 21, 2018 - link
You will get a new amoled phone/TV before it burns in.You will get a new iPhone before the battery cant maintain appropriate voltage.
Maybe I have a small drive or one which is written to a lot (or both) for witch 1000 P/E just doesn't cut it. Maybe I want to use the drive for a long time. Or, the craziest idea of them all maybe when I need a bigger drive I can ADD another one instead of replacing my old one (you know since the old one didn't burn through all of its P/E cycles).
This trend where you get a small price reduction for a lot lower quality is of great benefit to producing companies (Samsung already has a margin of about 75% on its memory chips) but very bad for the consumer (its already hard to find consumer MLC drives).
Oxford Guy - Saturday, July 21, 2018 - link
Is this the chant of the Planned Obsolescence Brigade?"You will be forced to get a new iPhone once your battery no longer maintains enough voltage."
"You will be forced to get a new TV before burn-in is an issue because of the use of cheap caps."
Etc.
porcupineLTD - Sunday, July 22, 2018 - link
Its not about planned obsolescence its about people defending bad/worse than already available technologies. The iPhone battery thing was a device design mistake. OLED burn in is a inherent issue of the technology (thats why Samsung despite being the best at OLED and the best at TVs makes no OLED TVs). The people here defending QLC look to me like the people that say burn in is not an issue on OLED devices or that the iPhone battery thing was not a problem since the 2 year guarantee is over so you should get a new device anyway. The technology is simply worse in almost every possible way than what we already have and the only reason we have QLC is for companies to extend their already huge margins when they could instead just expand capacity (thats why I mentioned Samsungs margin on memory chips) memory makers have huge margins but they still want to halve the production cost at the cost of durability, the fact that consumers will have to buy new drives earlier is just an added bonus.Oxford Guy - Saturday, July 21, 2018 - link
Drive death is not the only issue. Steady state performance for the original 120 GB 840 drive was horrendous, as documented at hardocpCheapSushi - Saturday, July 21, 2018 - link
Yeah, cost, size and total drive endurance, not cell endurance. Hard to believe enthusiasts are so bad at understanding said products.porcupineLTD - Sunday, July 22, 2018 - link
Lets use an example:Kingston SSDNow G2 240GB planar MLC - 300 TBW
Kingston A1000 240GB 3D TLC - 150 TBW
That looks to me like half the endurance when 3D TLC was supposed to have similar endurance to planar MLC, actualy if you look you will notice that manufacturers no longer provide TBW instead providing the more ambiguous and arbitrary MTBF (the reason I use Kingston drives as an example is because they still provide TBW) so there goes drive endurance.
As for cost, memory companies already have huge margins (Samsung approaching 75%) so most of the cost of the drives is from the profit the companies make not from the cost of making the NAND (they just want spend even less which is normal for for profit companies but that doesn't mean consumers should swallow their bullshit marketing) so there goes cost.
As for size that is the only somewhat good point, however size can be reduced by 33% just by going from 64L to 96L witch it did and could continue to do (dont know for how long) without sacrificing endurance, but Samsung sells 2TB single sided m2 drives so at least in the consumer space size does not seem to be a problem.
But hey, that's just my limited understanding based of my amateur observations, maybe a true enthusiast like yourself could shed some light on my unfounded concerns.
porcupineLTD - Sunday, July 22, 2018 - link
Edit: the TBW should be measured in TBAlso more examples:
Samsung 860 EVO 250GB TBW -150 TB MTBF - 1.500k h
Samsung 960 EVO 250GB TBW -100 TB MTBF - 1.500k h
Notice how the endurance went down between generations (I'm assuming because of a smaller node) but MTBF remained the same? :)
Bulat Ziganshin - Saturday, July 21, 2018 - link
with SLC->QLC transition capacity grows only linearly, while endurance fails exponentially. SLC had 100K cycles, while TLC with the same error-correction algos had only 500 cyclesit's pure math - with N bits per cell, you have only N times more capacity, but need to distinguish 2^N signal levels which, all things being equal, require to have 2^N bigger cell
CheapSushi - Saturday, July 21, 2018 - link
1000 cycles actuallyerple2 - Sunday, July 22, 2018 - link
That doesn't seem right. 2 bits per cell means you can store 4 pieces of info, instead of 2. At 3 bits per cell, it's 8 unique values per cell. at 4 bits per cell, it's 16 unique values. So QLC is, for the same physical size, 16x more dense.Back in the day, you could get a X-25E 32-ish gig drive that had roughly 100,000 P/E cycles. I don't know where you can buy SLC-only devices today. Nowadays, you can get a 2-4ishTB drive with only 1000 P/E cycles (about 50x-100x-ish the size). Given the relative size of the drive, the TBW is reasonably in the same ballpark, so I would expect endurance, as per measured in bytes written, to be the same order of magnitude. Given that several studies have suggested that the biggest limiting factor in drive replacement isn't really endurance failure, but other factors, it doesn't sound to me like fancy expensive high-endurance-on-a-per-cell basis is all that important.
porcupineLTD - Sunday, July 22, 2018 - link
TBW:Micron P300 200GB planar SLC - 3.5 Petabytes
Samsung 960 EVO 250GB 3D TLC - 100 Terabytes
The only reason for the reduced TBW was the small capacity, bigger capacity would stack with the superior endurance of SLC.
close - Sunday, July 22, 2018 - link
@bcronce, I perfectly agree that the SSD has a chance to fail for multiple other resins then failing cells. As I said in my previous comment I noticed this myself, albeit on a much smaller sample than Google's.But the fact that the SSDs might fail after the same TBW doesn't lead to the conclusion that MLC, TLC, and QLC have the same endurance but rather that SSD (as in the entire usint) tends to fail before you reach any of those limits.
A QLC cell will fail faster than a MLC all other things identical. It's physics. You can mitigate it with better error recovery algorithms, more spare space, bigger cell and manufacturing process but in the end it will still fail faster.
"Luckily" you might not notice because the rest of the SSD will give up before that. :)
DeepLake - Friday, July 20, 2018 - link
They may go bigger node for sure. They are saving alot by going 96L, they may aswell lose some by going larger node, maybe still pulling ahead a little in the end. Maybe yields are also abit higher than smaller node's. On the other hand QLC had issues with P/E voltage so they might benefit from smaller node. We can just speculate, im sure they are doing very well :DTyns - Saturday, July 21, 2018 - link
How many drive writes per day does the Seagate IronWolf 12TB workload rating rate it?.04 DWPD
This complaining opabout endurance is poppycock from people who are clueless. Buy optane drives of you need to a full drive write ever two hours.
CheapSushi - Saturday, July 21, 2018 - link
exactly, please they're acting as if they have SLC drives themselves. LOL sure.PeachNCream - Saturday, July 21, 2018 - link
If you feel so secure about QLC, why bother to raise such a stink and further quote an as-yet unproven endurance rating (1000 P/E cycles - when 500 is the current capability of existing QLC products for sale today)? It's clear you aren't entirely secure in your opinion and feel the need to lash out at others to address your insecurities. I mean you're also the same person that didn't know in 2018 that Killer announced a switch to Intel NICs in 2016.BillBear - Monday, July 23, 2018 - link
Isn't it true that one of the things that happened when they moved to 3D flash was that they also moved to an older, larger process node that had better endurance, and that adding more layers made up for the fact that each individual component in the layers of the chip were larger?That was my understanding of what would happen when 3D Flash was still theoretical.
Did something change since then?
watzupken - Saturday, July 21, 2018 - link
QLC is probably going to be great for those that are using their SSD for storage/ backup purpose. No matter what the manufacturers claim, QLC's endurance is going to be poor. It is typical marketing to downplay flaws. It will only be interesting if the price is right.Death666Angel - Saturday, July 21, 2018 - link
"It will only be interesting if the price is right." is true of everything.Tyns - Saturday, July 21, 2018 - link
96L QLC doubles the bit density of 64L TLC, so prices should halve.Also note that BiCS3 bit density at 72L is equal to IMFT NAND at 64L, so BiCS is way behind for equal layers with IMFT.
Oxford Guy - Saturday, July 21, 2018 - link
Should and will are two different things. The price of the Calyos case has more than doubled.Cliff34 - Thursday, July 26, 2018 - link
The market price is never determined solely on manufacturing cost.Luckz - Monday, July 23, 2018 - link
From what I gathered SSDs don't get along so well with being a written to, then powered off for a long time style backup device.Not sure if QLC has equal or worse issues in that use case.