Upgrade from PCIe 3.0 NVME SSD to PCIe 4.0?

GotNoRice

GotNoRice

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I'm currently running a Samsung 960 Pro NVME SSD. That is a PCIe 3.0 M.2 Drive. Now that I've upgraded to a PCIe 4.0 capable x570 chipset motherboard, it makes me wonder if it would be worth it to upgrade my SSD. My questions are:

-Would I gain anything other than sequential read/write speed?

-Which drive would be preferable if comparing a PCIe 3.0 MLC drive (such as my Samsung 960 Pro) to a potential PCIe 4.0 TLC (or even QLC) drive?
 
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No, and none (maybe). The current consumer 4.0 drives available are very much sequential-focused and also very much not like MLC. They have full-drive SLC caching which means all of the TLC can use single-bit mode at the cost of taking up three times the capacity. This is very unlike MLC drives which have no SLC caching. While SLC of this nature can be superior to MLC it has many drawbacks that would make it a poor choice for areas where you'd be using a MLC drive. Future 4.0 drives may buck this trend, although currently the E18 as taped out will be much the same but with just higher sequentials than the current E16. 4.0 as a whole is about bandwidth.

NVMe 1.4 controllers will have other advantages and a properly designed drive can be MLC-like. A good example would be the WD SN750 which has only a small, static SLC cache (for consumer use and benchmarks) but is otherwise very consistent and efficient with steady state workloads, especially writes. It's also possible for drives to engage in MLC (2-bit) mode - it's rumored some of the Realtek-based drives do this - which would mean a TLC-based drive could de facto be treated as a smaller MLC drive (e.g. 1TB of TLC = 667GB of pMLC) but MLC mode is inherently inferior to true MLC. If you'd like to know more about these subjects I cover them extensively on Reddit.

My advice in general is to avoid the current crop of 4.0 drives unless you have a system with multiple NVMe (and lanes - even X570 is questionable) and need the bursty sequential performance. Again, though, these drives in SLC mode can be compellingly fast even in comparison to the Samsung Pro drives which is why so many reviewers/YouTubers say things like the SX8200 Pro matches the 970 Pro...which is patently ridiculous if you're doing any sort of workload where you'd want MLC. But don't get me started. :)

I also have X570 and currently I use the SN750 as my workspace drive as it's been cheap recently and is somewhat MLC-like at much lower cost. The Samsung 970 EVO Plus is arguably even closer to the Pro in performance profile thanks to its 96L TLC and static + (relatively small) dynamic SLC caching, although I think it's more balance towards consumer. That's about it for "consumer" drives.
 
Maxx said:
No, and none (maybe). The current consumer 4.0 drives available are very much sequential-focused and also very much not like MLC. They have full-drive SLC caching which means all of the TLC can use single-bit mode at the cost of taking up three times the capacity. This is very unlike MLC drives which have no SLC caching. While SLC of this nature can be superior to MLC it has many drawbacks that would make it a poor choice for areas where you'd be using a MLC drive. Future 4.0 drives may buck this trend, although currently the E18 as taped out will be much the same but with just higher sequentials than the current E16. 4.0 as a whole is about bandwidth.

NVMe 1.4 controllers will have other advantages and a properly designed drive can be MLC-like. A good example would be the WD SN750 which has only a small, static SLC cache (for consumer use and benchmarks) but is otherwise very consistent and efficient with steady state workloads, especially writes. It's also possible for drives to engage in MLC (2-bit) mode - it's rumored some of the Realtek-based drives do this - which would mean a TLC-based drive could de facto be treated as a smaller MLC drive (e.g. 1TB of TLC = 667GB of pMLC) but MLC mode is inherently inferior to true MLC. If you'd like to know more about these subjects I cover them extensively on Reddit.

My advice in general is to avoid the current crop of 4.0 drives unless you have a system with multiple NVMe (and lanes - even X570 is questionable) and need the bursty sequential performance. Again, though, these drives in SLC mode can be compellingly fast even in comparison to the Samsung Pro drives which is why so many reviewers/YouTubers say things like the SX8200 Pro matches the 970 Pro...which is patently ridiculous if you're doing any sort of workload where you'd want MLC. But don't get me started. :)

I also have X570 and currently I use the SN750 as my workspace drive as it's been cheap recently and is somewhat MLC-like at much lower cost. The Samsung 970 EVO Plus is arguably even closer to the Pro in performance profile thanks to its 96L TLC and static + (relatively small) dynamic SLC caching, although I think it's more balance towards consumer. That's about it for "consumer" drives.
Click to expand...
Maxx,

How long in your estimation before there are 4.0 drives that truly support MLC access? How can we tell when we see all the different vendor claims?

What is your subreddit?
 
x509 said:
Maxx,

How long in your estimation before there are 4.0 drives that truly support MLC access? How can we tell when we see all the different vendor claims?

What is your subreddit?
Click to expand...

Subreddit (check my profile, too, or use it to search for posts)

In general the industry is moving away from MLC, actually. This is why Samsung didn't make an OEM version of the 970 Pro and also has no 2TB SKU for it. Enterprise is a different story. Also why Samsung has had 4.0 enterprise drives out but no consumer ones yet - and they call them "never-dying" despite being TLC-based. In fact QLC demand in enterprise has been quite high. (so those MLC lovers who loved to talk trash on TLC are in for a rude awakening) That being said there's still a demand for SLC, Optane, eMLC/pMLC, just not in the same market as the 970 Pro.

Both SMI and Phison have (native) 4.0 controllers in the works which we will see in 2020. Budget and high-end variants. WD uses proprietary now, not sure about the future as they have invested in RISC-V (most consumer SSD controllers are based on the ARM Cortex-R series). Samsung's Polaris/Phoenix in their current drives is capable of more, not sure what direction they will go just yet though. Toshiba (which got the remnants of Indilinx) also has embedded and proprietary designs for client usage. SK Hynix seems to be moving aggressively in the space as well (128L + proprietary controller built on LAMD). Seagate has the old SandForce tech. Etc.

It's an interesting question because 4.0 is ultimately about bandwidth and SLC mode (with TLC/QLC drives) will get you there quicker. There's even PLC drives on the horizon and it's possible we'll see MLC mode as standalone or as a separate tier. The NVMe 1.4 spec is quite flexible as well...
 
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Maxx said:
Subreddit (check my profile, too, or use it to search for posts)

In general the industry is moving away from MLC, actually. This is why Samsung didn't make an OEM version of the 970 Pro and also has no 2TB SKU for it. Enterprise is a different story. Also why Samsung has had 4.0 enterprise drives out but no consumer ones yet - and they call them "never-dying" despite being TLC-based. In fact QLC demand in enterprise has been quite high. (so those MLC lovers who loved to talk trash on TLC are in for a rude awakening) That being said there's still a demand for SLC, Optane, eMLC/pMLC, just not in the same market as the 970 Pro.

Both SMI and Phison have (native) 4.0 controllers in the works which we will see in 2020. Budget and high-end variants. WD uses proprietary now, not sure about the future as they have invested in RISC-V (most consumer SSD controllers are based on the ARM Cortex-R series). Samsung's Polaris/Phoenix in their current drives is capable of more, not sure what direction they will go just yet though. Toshiba (which got the remnants of Indilinx) also has embedded and proprietary designs for client usage. SK Hynix seems to be moving aggressively in the space as well (128L + proprietary controller built on LAMD). Seagate has the old SandForce tech. Etc.

It's an interesting question because 4.0 is ultimately about bandwidth and SLC mode (with TLC/QLC drives) will get you there quicker. There's even PLC drives on the horizon and it's possible we'll see MLC mode as standalone or as a separate tier. The NVMe 1.4 spec is quite flexible as well...
Click to expand...
So I guess I asked the wrong question. Maybe the right question is, when will true QLC drives with full performance for PCI-E 4.0 become available?

I'm asking because sometime early in 2020, I will build an AMD Ryzen based system using an X570 motherboard. I build my systems for 5+ years, so eventually I will want a PCI-E 4 graphics and NMVe SSD. However, I could hold off buying the NMVe drive for a few months if necessary.
 
x509 said:
So I guess I asked the wrong question. Maybe the right question is, when will true QLC drives with full performance for PCI-E 4.0 become available?

I'm asking because sometime early in 2020, I will build an AMD Ryzen based system using an X570 motherboard. I build my systems for 5+ years, so eventually I will want a PCI-E 4 graphics and NMVe SSD. However, I could hold off buying the NMVe drive for a few months if necessary.
Click to expand...

The first full performance (TLC) 4.0 drives are expected in retail starting in Q3 2020 with the Phison E18. SMI might have a high-end controller available sooner but it won't be as fast. The E18 should be similar to the current E16 (4.0) design but with more horsepower - tri-CPU with co-processors - but in a much smaller process node, so not taking up much more power. However it will be able to leverage 128L/BiCS5 flash at up to 1200 MT/s (E16 uses BiCS4 at 800 MT/s) which is basically 7 GB/s in an eight-channel design. The CPU is likely a straight upgrade which means 50% max IOPS over the base E12 (E16 is based off of the E12) or in other words, up to 1 million read/write IOPS. You likely won't see QLC on this controller but rather the E19T which is a weaker design.

The E18 as planned should follow the E16 in using full-drive SLC as I said earlier, which means it's not really MLC-like in its performance profile. But if you're looking for maximum peak performance, this will be it. It's likely SMI will follow up their SM2262/EN with something that's better in real world terms (e.g. low queue depth) but won't have the same raw power. So if you're looking for something with the E18's power but without the caching it'll probably be a waiting game for WD and Samsung, of which I have no word yet. Hynix is also in the mix - their technology is built on LAMD designs which historically are not powerhouses. So if you're waiting for full-throttle PCIe 4.0 drives, TLC-based with consistent and heavy performance (and not just SLC caching), I'm thinking Q4 for WD/Samsung but I can't 100% commit to that yet.
 
even a samsung 960 evo is overall faster then most pci-e 4 nvme ssds in real world normal use at the moment , 64QD seq is not typically real world use you should be looking at the 4k numbers which samsung are typicky the best at the moment
 
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