Flash is generally a bad choice for long-term storage. The memory state is stored by holding a charge inside a tiny cell (for MLC or TLC, the voltage of the charge matters). Over time, that charge slowly leaks out.
Back when NAND cells were huge, this rate of discharge wasn't significant. But as NAND has gotten smaller, the ratio of surface area (corresponds to discharge rate) to volume (corresponds to stored charge) has gone up, leading to quicker discharge. This is what caused all the Samsung 840 EVO problems - the NAND cells had gotten so small that they were discharging enough in a few months that the hardware was having difficulty reading the stored value. The checksum didn't match and the hardware tried over and over again to read the cell, which is what caused the loss of speed.
I have some SD cards which still retain their data after 10 years. But I've had other SD cards lose some of their data in as little as 3 years. If you need archival storage, use media that's rated for archival storage (optical and especially M-DISC).
My point is that while you could design a NAND controller which occasionally refreshed the cells to maintain their information indefinitely, this requires the drive to have power.
"Archival" generally means put it on a shelf and forget about it for years or even decades. I'm very skeptical flash memory could ever be adapted to satisfy this criterion. And this is how I interpreted OP's question about 10-20 years in "cold storage". Toshiba seems to be (mis)using the term to mean data you don't need to access very quickly.
"My point is that while you could design a NAND controller which occasionally refreshed the cells to maintain their information indefinitely, this requires the drive to have power."
No they won't need to be powered to maintain information just a bigger node that has little to no voltage leakage, my guess is they'll use 55 nm for QLC NAND. Even current SSD on 15-16 nm can hold their data for at least 6 months without any power.
In the link they're talking about endurance somewhat above current MLC NAND. This usually refers to write endurance, whereas the OP was concerned about data retention time. For that task NAND is a terrible choice.
I read a few years ago, the total bits, of NAND, compared to HDD, is still very small. Many Desktop are still selling with HDD ( For some strange reasons ). I am wondering when is the tipping point. Surely Desktop computers aren't sold in much volume in 2017
240 million "computers" sold in 2015 (which apparently means "desktop PCs, mobile PCs, and servers using the Intel x86 processor architecture" according to the data source)
So, for context, that's slightly under the sales of iPhones every year. The iPhones come with, what, let's say about 64GB of flash, the PCs with, what, maybe 500GB of HD. Of course there are other phones, and tablets, and PCs that don't suck, but it seems plausible.
Then of course there's all the HDs that are sold for archive -- either home backup/media center or for data warehouses. Again, sure, some people use flash for these purposes, but most of the people using flash are doing it in an accelerator role (use 500GB of flash to kick up the speed of your 10TB array or whatever).
"Many Desktop are still selling with HDD ( For some strange reasons )."
Well, there are actual several 'strange reasons' for this:
1) Cost per gigabyte. A cheap ~500GB SSD is about $0.23/GB, ~$110, for that you can get a 3TB HDD, about $0.037/GB, or even a slower 4TB one for $0.028/GB. So for when price/performance is secondary to price/capacity, say in a cheap office computer or home computer for someone on a tight budget, the a HDD is preferred.
2) Where you want both performance and capacity, then often a desktop will be sold with both a SSD for OS/apps/swap and a HDD for data storage, thus still selling HDDs for these desktops.
3) NAND fab capacity simply cannot physically produce enough NAND to supply all desktops in addition to the demand from phones, laptops, thumbdrives, enterprise and other demands.
We are currently heading into a short-medium term NAND shortage. So expect SSD prices, and any other low-margin NAND incorporating products that can't absord a price rise (e.g. high-margin products like iphones may be able to absorb a NAND price hike) to go up for 12-24 months while companies like SK Hynix expand fab capacity. Thus perhaps making the price/capacity tilt even more towards HDD until the fab issues are sorted.
In Korea, they are rolling out 5G internet, and making these huge investments in technology. Hynix spends $2.6 billion on a new fab, while Samsung's just built two new fabs that cost over $25 billion each. Hynix intends to spend $38.28 billion on fabs in the mid and long-term future.
Meanwhile in the USA, Trump wants to bring back the coal industry. SMH
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Kristian Vättö - Friday, December 23, 2016 - link
HBM is just fancy die stacking, not wafer level 3D like 3D NAND. The cell architecture of DRAM makes any sort of wafer level 3D impossible.baka_toroi - Friday, December 23, 2016 - link
We are going to need all the 3D NAND we can get our hands on to store all the Wikileaks files that will be released.Question: is 3D NAND flash good enough as a cold storage media for 10~20 years? I have ZIP discs that can still be read... I think.
vladx - Friday, December 23, 2016 - link
They will be, just wait for QLC SSDs which will mostly be produced for archiving purposes.sonicmerlin - Friday, December 23, 2016 - link
They experience massive data loss after a year of not being powered.Solandri - Saturday, December 24, 2016 - link
Flash is generally a bad choice for long-term storage. The memory state is stored by holding a charge inside a tiny cell (for MLC or TLC, the voltage of the charge matters). Over time, that charge slowly leaks out.Back when NAND cells were huge, this rate of discharge wasn't significant. But as NAND has gotten smaller, the ratio of surface area (corresponds to discharge rate) to volume (corresponds to stored charge) has gone up, leading to quicker discharge. This is what caused all the Samsung 840 EVO problems - the NAND cells had gotten so small that they were discharging enough in a few months that the hardware was having difficulty reading the stored value. The checksum didn't match and the hardware tried over and over again to read the cell, which is what caused the loss of speed.
I have some SD cards which still retain their data after 10 years. But I've had other SD cards lose some of their data in as little as 3 years. If you need archival storage, use media that's rated for archival storage (optical and especially M-DISC).
vladx - Saturday, December 24, 2016 - link
Like I said above, QLC NAND while slower will be especially targeted towards archival: https://www.custompcreview.com/news/fms-2015-toshi...It's all about the controller which no doubt will need significant changes to allow for long-term storage.
Solandri - Saturday, December 24, 2016 - link
My point is that while you could design a NAND controller which occasionally refreshed the cells to maintain their information indefinitely, this requires the drive to have power."Archival" generally means put it on a shelf and forget about it for years or even decades. I'm very skeptical flash memory could ever be adapted to satisfy this criterion. And this is how I interpreted OP's question about 10-20 years in "cold storage". Toshiba seems to be (mis)using the term to mean data you don't need to access very quickly.
vladx - Sunday, December 25, 2016 - link
"My point is that while you could design a NAND controller which occasionally refreshed the cells to maintain their information indefinitely, this requires the drive to have power."No they won't need to be powered to maintain information just a bigger node that has little to no voltage leakage, my guess is they'll use 55 nm for QLC NAND. Even current SSD on 15-16 nm can hold their data for at least 6 months without any power.
MrSpadge - Tuesday, December 27, 2016 - link
In the link they're talking about endurance somewhat above current MLC NAND. This usually refers to write endurance, whereas the OP was concerned about data retention time. For that task NAND is a terrible choice.vladx - Wednesday, December 28, 2016 - link
In that link, they're also talking about archival SSDs which automatically implies long-term storage.BrokenCrayons - Friday, December 23, 2016 - link
This is FAB-ulous news for SK Hynix!Lolimaster - Friday, December 23, 2016 - link
SK Hynix has probably the best logo and the most beautifully designed SSD.iwod - Friday, December 23, 2016 - link
I read a few years ago, the total bits, of NAND, compared to HDD, is still very small. Many Desktop are still selling with HDD ( For some strange reasons ). I am wondering when is the tipping point. Surely Desktop computers aren't sold in much volume in 2017name99 - Saturday, December 24, 2016 - link
240 million "computers" sold in 2015 (which apparently means "desktop PCs, mobile PCs, and servers using the Intel x86 processor architecture" according to the data source)So, for context, that's slightly under the sales of iPhones every year. The iPhones come with, what, let's say about 64GB of flash, the PCs with, what, maybe 500GB of HD. Of course there are other phones, and tablets, and PCs that don't suck, but it seems plausible.
Then of course there's all the HDs that are sold for archive -- either home backup/media center or for data warehouses. Again, sure, some people use flash for these purposes, but most of the people using flash are doing it in an accelerator role (use 500GB of flash to kick up the speed of your 10TB array or whatever).
eldakka - Sunday, January 1, 2017 - link
"Many Desktop are still selling with HDD ( For some strange reasons )."Well, there are actual several 'strange reasons' for this:
1) Cost per gigabyte. A cheap ~500GB SSD is about $0.23/GB, ~$110, for that you can get a 3TB HDD, about $0.037/GB, or even a slower 4TB one for $0.028/GB. So for when price/performance is secondary to price/capacity, say in a cheap office computer or home computer for someone on a tight budget, the a HDD is preferred.
2) Where you want both performance and capacity, then often a desktop will be sold with both a SSD for OS/apps/swap and a HDD for data storage, thus still selling HDDs for these desktops.
3) NAND fab capacity simply cannot physically produce enough NAND to supply all desktops in addition to the demand from phones, laptops, thumbdrives, enterprise and other demands.
We are currently heading into a short-medium term NAND shortage. So expect SSD prices, and any other low-margin NAND incorporating products that can't absord a price rise (e.g. high-margin products like iphones may be able to absorb a NAND price hike) to go up for 12-24 months while companies like SK Hynix expand fab capacity. Thus perhaps making the price/capacity tilt even more towards HDD until the fab issues are sorted.
Bundy - Saturday, April 21, 2018 - link
In Korea, they are rolling out 5G internet, and making these huge investments in technology. Hynix spends $2.6 billion on a new fab, while Samsung's just built two new fabs that cost over $25 billion each. Hynix intends to spend $38.28 billion on fabs in the mid and long-term future.Meanwhile in the USA, Trump wants to bring back the coal industry. SMH