News Solidigm Introduces Industry-First PLC NAND for Higher Storage Densities

[Admin]

SK hynix-owned Solidigm took to the Flash memory Summit 2022 to showcase its working prototype SSD based on Penta Level Cell (PLC) NAND, which promises to bring density increases to a market thirsty for storage.

Solidigm Introduces Industry-First PLC NAND for Higher Storage Densities : Read more

 

[bit_user]

I'm still wondering who's the idiot responsible for the "L" in "xLC". Should be a xBC for "x Bits per Cell".

For a few years, I was operating under the assumption that TLC meant storing 1.5 bits per cell, rather than 3.

P.S. I'm still trying to avoid QLC as much as I can. This new development should be very unwelcome by anyone who values data retention and integrity.

 

[cyrusfox]

Amazing to see PLC out so early, nice work Intel/Solidigm (Crappy new name though...)

This new development should be very unwelcome by anyone who values data retention and integrity.

Have you wore out a SSD yet through read/write cycles? I am still using a OCZ Vertex 4 that were notorious for dying early. I have a 660p QLC 512GB drive showing 80% life left which has been in service for 3 years now(It only boast 200cycles). PLC will work out fine, As long as it can do 100+ cycles, that coupled with the latest controllers and SLC cache to smooth out the experience, these will be great to put price pressure on the TLC charge trap everyone else is making in the consumer space. PLC should easily outlast the useful life of the laptops and are easy to swap out and use as a fast m.2 external storage drive if you want something more performant.
For my heavy write/scratch drives, I use old server grade Intel and Samsung drives for pennies per GB(SATA drives with rated for 10-20k cycles).

 

[bit_user]

Have you wore out a SSD yet through read/write cycles?

That's only one way to lose your data. The other is simply to leave it turned off for too long. As cells become smaller and packed with more bits, that power-off data retention time quickly dwindles.

these will be great to put price pressure on the TLC charge trap everyone else is making in the consumer space.

Winning a race to the bottom is no victory for anyone.

For my heavy write/scratch drives, I use old server grade Intel and Samsung drives for pennies per GB(SATA drives with rated for 10-20k cycles).

You assume that will always be an option, but they're starting to use different form factors that are much less consumer-friendly and ship in capacities that limit us to buy heavily used drives pulled from decommissioned servers. Not a very attractive alternative.

 

[edzieba]

P.S. I'm still trying to avoid QLC as much as I can. This new development should be very unwelcome by anyone who values data retention and integrity.

We've seen the exact same proclamations of impending data-loss and drive-failure when MLC overtook SLC for the majority of drives sold, when TLC overtook MLC for the majority of drives sold, and when QLC overtook TLC for the majority of drives sold. The sky has resolutely refused to fall.

 

[AgentBirdnest]

I'm pretty excited about this (which seems like an unpopular opinion.) I'd love to have a cheaper, large capacity SSD for a media drive. Don't care about write speeds or endurance, since I'd probably only write to it once.
I hope it comes before 2026...

 

[bit_user]

We've seen the exact same proclamations of impending data-loss and drive-failure when MLC overtook SLC for the majority of drives sold, when TLC overtook MLC for the majority of drives sold, and when QLC overtook TLC for the majority of drives sold. The sky has resolutely refused to fall.

There are a few reasons for this. First, error correction schemes have gotten better. Second, cell designs have improved. However, both of those are not wells you can keep going back to. I'd guess both are beyond the point of diminishing returns.

The other thing you're ignoring is what I said about power-off data retention time. I have an ebook reader that I bought in 2019. I went maybe 4-6 months without using it and its storage was toast. I had to factory-reset it. I have > 10-year-old USB sticks which still have files I wrote when I got them. New USB sticks won't come anywhere close to such retention times.

For a device you use every day, QLC and even PLC is fine. However, such experiences don't translate to other usage models.

 

[bit_user]

I'm pretty excited about this (which seems like an unpopular opinion.) I'd love to have a cheaper, large capacity SSD for a media drive.

Here's why it's a bad tradeoff. They're halving the voltage difference between two distinct values, for the benefit of only 25% more bits per cell. Your media drive is going to be a lot more failure-prone, for the benefit of only 25% more capacity. If you really care about what's on it, that's not a risk I'd take.

And unlike hard disk errors, you can't very well mitigate the issue of dwindling power-off data retention through RAID, because all of your SSDs are going to suffer charge decay at roughly the same rate. So, if one drive falls off the cliff, chances are the others will have, also.

 

[GoboII]

Bit of a typo in the article, TLC would provide 50% more data density compared to MLC, going from 2 to 3 layers per cell. Similarly, QLC would be a 33% increase over TLC, and PLC would be a 25% increase over QLC.