SSD's got even bigger? PLC nand

[Origami Cactus]

My reason for title edit:

I copied a 400GB file off of a QLC SSD, and it stayed at 1GB/s read the whole time, so QLC only has slow writes, but reads are very good. So probably that is the same for PLC.

So i am considering a PLC SSD for a game drive (if they make a 8tb one), because the first copy will be slow, but all the game load times will be very good. That is the reason i use a 660p as a game drive right now, because yes it is only 80mb/s write, but read is 1.8GB/s, so very fast game load times.

 

 

 

https://arstechnica.com/gadgets/2019/09/new-intel-toshiba-ssd-technologies-squeeze-more-bits-into-each-cell/?amp=1

 

Quote

Wednesday, Intel announced it's joining Toshiba in the PLC (Penta-Level Cell, meaning 5 bits stored per individual NAND cell) club. Intel has not yet commercialized the technology, so you can't go and buy a PLC SSD yet—but we can expect the technology will lead eventually to higher-capacity and cheaper solid state drives.

 

Quote

Unfortunately, while PLC SSDs will likely be bigger and cheaper, they'll probably also be slower. Modern SSDs mostly use TLC storage with a small layer of SLC write cache. As long as you don't write too much data too fast, your SSD writes will seem as blazingly fast as your reads—for example, Samsung's consumer drives are rated for up to 520MB/sec. But that's only as long as you keep inside the relatively small SLC cache layer; once you've filled that and must write directly to the main media in real time, things slow down enormously.

 

My thoughts:

 

Hope it doesn't make it's way into consumer products any time soon.

It would have the same use as QLC drives now, steam library drive, or some other use case, that can live with slow writes, but likes really fast reads.

QLC is already really slow at only 80-120mb/s for sustained writes, so this will be even slower, but reads should be good.

Also it doesn't benefit that much:

 

Space increase per cell increase:

SLC 

MLC +100%

TLC +50%

QLC +33%

PLC +25%?

 

Also another question is durability.

I would only consider PLC, if you could get it in 6+TB capacities, and for the a little more than hdd of same size.

Because it will be slower than a hdd for sequantial writes,, but atleast it will be fully silent, and everything else will be faster, especially reads.

 

 

[Ashley MLP Fangirl]

why would you post only a link first and then edit it? just to be the first poster of the topic?

 

either that or my computer has issues. 

 

because I clicked on the notification immediately, it was only a link, then I refreshed the page and the text was there. 

[Pixel5]

id say it would be awesome if this would make it into consumer SSD´s as fast as possible.

 

you will always be able to pay more and get real SLC memory if you want to but the reality is most data is only written once and then has small changes made to it later so the write speed is not really important.

at the same time you still get the advantage of very fast read speeds which is the real benefit of SSD´s

[minibois]

I can't wait for companies to use this tech and market it as a great thing!

Can we get a sequel?! "How SSD tech keep getting worse-er still!!"

 

The worst thing about tech like this is that laptops will use whatever sort of drive they like and not mention that in their spec sheets. Now suddenly you're comparing a 250GB TLC SSD to a 500GB QLC and 750GB PLC drive and people thinking it's the same across the board (I'm probably off with my math, don't care at the moment).

[Origami Cactus]

1 minute ago, VegetableStu said:

rage aside, I feel like the more levels a cell needs to represent, the sooner write-heavy operations would kill it ._.

 

so like outside of wire-and-store-forever use cases I'm not sure where can 5 levels be used

That is precisely the case, look at the durability differences between 1tb  samsung 860qvo (QLC), Samsung 860evo (TLC) and 860 pro (MLC).

[rEkmAInc1csBnlM6C85H]

 

[WereCatf]

17 minutes ago, Pixel5 said:

id say it would be awesome if this would make it into consumer SSD´s as fast as possible.

 

you will always be able to pay more and get real SLC memory if you want to but the reality is most data is only written once and then has small changes made to it later so the write speed is not really important.

at the same time you still get the advantage of very fast read speeds which is the real benefit of SSD´s

I've got a QLC-drive for my games and I don't think I'd see any meaningful difference from using a PLC-drive, so I agree. PLC could also be nice for use in my server for a lot of the stuff that's rarely written to or modified.

[Origami Cactus]

6 minutes ago, WereCatf said:

I've got a QLC-drive for my games and I don't think I'd see any meaningful difference from using a PLC-drive, so I agree. PLC could also be nice for use in my server for a lot of the stuff that's rarely written to or modified.

My main problem would be the durability aspect, it only adds 1 more bit, but to save it, instead of 16 different voltages of QLC, it now needs 32.

So the differences between different voltage states is much smaller, making the drive more error prone, and reducing the life span. Also if the drive is without power, it will loose it's data even faster than QLC.

Yes it has it's use cases, but i would like to see a cheap 8TB QLC ssd before that.

 

[Drak3]

30 minutes ago, VegetableStu said:

3LC. 4LC. 5LC.

Technically, it already is. Just need to brush up on your Greek numeral prefixes.

[The Torrent]

Tlc is as low as I will go, and even then I’ll never fill over 50% capacity.

[5x5]

This is literally the point where an HDD makes more sense as a product. Who in their right mind thinks making an SSD slower than a 5400RPM HDD is a good idea?

[WereCatf]

7 minutes ago, Origami Cactus said:

Yes it has it's use cases, but i would like to see a cheap 8TB QLC ssd before that.

Doesn't look like that'll happen anytime soon I mean, cheap is relative and all that, but 8TB HDDs are about 200€ over here, ie. about 40GB/€ -- I'm not aware of any SSDs getting even close.

[WereCatf]

Just now, 5x5 said:

This is literally the point where an HDD makes more sense as a product. Who in their right mind thinks making an SSD slower than a 5400RPM HDD is a good idea?

Depends on whether one is talking about read- or write-speeds. There are PLENTY of cases where slow writes don't matter.

[strajk-]

Well, it's good for archiving, so I'm happy on that end. 

But I'll be angry either way because it will be marketed as a daily driver for consumers, just like Samsungs QVO lineup. 

-"But...but...it's an SSD, why isn't it faster??!!" 

Can't wait to have this discussion again... 

[5x5]

Just now, WereCatf said:

Depends on whether one is talking about read- or write-speeds. There are PLENTY of cases where slow writes don't matter.

Reads are also not good, though. And considering how low the durability is

[WereCatf]

1 minute ago, 5x5 said:

Reads are also not good

Oh, you've got access to one?

[leadeater]

7 minutes ago, 5x5 said:

Reads are also not good, though. And considering how low the durability is

Even if the reads are only 200MB/s-250MB/s (which is lower than I expect) that's still faster than an HDD and the access latency times will be below ms to less than 3ms (bar cases where it makes no difference) so will still be much faster than an HDD, even a good 7200 rpm.

 

Remember back to the first generation of SSDs that were barely faster than WD VelociRaptors of the time? Usability and feel of those SSDs were still much better, no seek times = better.

[WereCatf]

9 minutes ago, leadeater said:

Even if the reads are only 200MB/s-250MB/s (which is lower than I expect)

Personally, I would think actual read-speeds will be closer to SATA SSD-speeds. Then again, I'm not an expert and I could be completely off the mark. I hope to see some Anandtech-reviews soon!

[leadeater]

9 minutes ago, VegetableStu said:

Hexa and Hepta; and Deca and Dodeca?

Doduo and Dodrio

[porina]

Write performance might suck but will be mitigated in a similar way to currently with adaptive SLC cache, so for normal use it wont be noticed. Assuming it lowers cost enough it could enable higher capacities, so there is some scope for improvement through parallel writes. If you need higher performance, you can still get it, at a higher cost.

[Flying Sausages]

[WereCatf]

4 minutes ago, VegetableStu said:

Hitmonlee, Hitmonchan, and Hitmontop

Err....ummm...

[Dabombinable]

So...we'll soon have SSD with lower write (once out of SLC cache) speeds than my 2004 200GB SATA 1 drives. Well that's bloody stupid.

[Dabombinable]

Just now, VegetableStu said:

inb4 SLI SSD controllers ._. to split the write operation into two so that they write two blocks at a time

That'd remove the price difference though, so you'd pay the same for worse 
 

Spoiler

Thought of it before, internal striping across NAND would be pretty awesome though - around 320MB/sec writing QLC instead of 80MB/sec or slower than 2010 laptop drive.

 

[TrainFan475]

PLC? ugh. I thought it couldn't get any worse. Just get a hard drive at this point.