Getting ready for Microsoft's Direct Storage Solution.

[steakrocks123]

I've been in the process of getting my PC set for windows 11's "Direct Storage" solution, in which the graphics card has direct access to storage, forgoing the processing that has been done previously on the CPU. I've been on the look out to get a 3080 for a decent price for a while now (Not too stressed about it, as my gtx 1060 has been serving me just fine for now), and I'm also looking to set up an nvme raid (raid 1) for my game drive. Here's where the question comes in.

 

I'm not sure it it will actually be worth it spending the extra money to have the drives be pci gen 4. From what I've been able to tell, it's about double the raw performance per drive to go to gen 4.0 instead of gen 3.0 (2GB/s per lane vs. 1GB/s per lane). Would there be any point to going gen 4 vs gen 3 assuming my setup has the lanes to support them?

[ki8aras]

if direct storage actually becomes a thing and is implemented by game devs on pc then yeah, the extra bandwidth would probably help

[cacoe]

Hard to say whether there will be a difference in gaming performance at this point because we have nothing to test yet. Gen4 provides faster sustained reads and writes, there's currently not nearly as much gain on random reads or writes though which is probably what is going to make the biggest difference. 

 

That all said, I think you're better getting a good nvme gen 3 drive rather than a bad nvme gen 4 drive.

 

(see my specs, my gen 3 drive is faster than my gen 4, thinking about changing the boot drive for something else)

[steakrocks123]

@cacoe That's interesting, from what I had seen, I would have assumed that the sabrent rocket line was higher quality. That drive is actually the same one I was looking to get to populate the raid (1TB drives instead of 256GB). Are there any know issues with these Sabrient drives, or is it possible that your drive is just filling up and therefore losing performance?

[cacoe]

9 minutes ago, steakrocks123 said:

@cacoe That's interesting, from what I had seen, I would have assumed that the sabrent rocket line was higher quality. That drive is actually the same one I was looking to get to populate the raid (1TB drives instead of 256GB). Are there any know issues with these Sabrient drives, or is it possible that your drive is just filling up and therefore losing performance?

I think the actual NAND chips are crap (at least on the lower capacity ones) so as soon as the cache fills, it's slowsville, either that or I have a faulty drive. I'm about 50% full and get generally atrocious write speeds, lower than SATA SSDs just on that drive. You might have better luck with the higher capacity variants.

Original plan was just get gen4 for the system drive, so windows and a few programs are as snappy as possible but it didn't really pan out that way. Didn't need a huge system drive but I think I'll need to upgrade now.

[StDragon]

Games have to be coded to utilize DirectStorage.

 

What I'm curious to know is if existing DirectX12 titles can be patched to utilize this feature, or if the game engine has to be coded under a new paradigm of resource management at its core; meaning only for new titles.

[cacoe]

1 minute ago, StDragon said:

Games have to be coded to utilize DirectStorage.

 

What I'm curious to know is if existing DirectX12 titles can be patched to utilize this feature, or if the game engine has to be coded under a new paradigm of resource management at its core; meaning only for new titles.

Seems to me it's almost certain that the game will need to be programmed for it on a title by title basis as they currently deal with how textures and assets load in to ram on their own. If it's a game that relies on a big engine, like Unreal or Unity, I imagine less work could be required on how the original title works but a patch will still need to be provided.

[Chris Pratt]

3 minutes ago, StDragon said:

Games have to be coded to utilize DirectStorage.

 

What I'm curious to know is if existing DirectX12 titles can be patched to utilize this feature, or if the game engine has to be coded under a new paradigm of resource management at its core; meaning only for new titles.

It's mostly about enabling new experiences. Games can already benefit from faster load times with NVMe storage today. Where DirectStorage comes into its own is with stuff like the Medium and Ratchet and Clank: A Rift Apart, where you can have mostly seamless transitions between different rendered worlds. It will also have an impact in open world games, eventually, as less of the world has to be rendered at any given time because missing pieces can be streamed in dynamically as they're need. This all requires rethinking how games are designed, though, so it's not really something you can patch into existing games.

[Chris Pratt]

Microsoft has already publicly stated that PCIe 3.0 is all that's required for DirectStorage features. There may be additional benefit to faster PCIe 4.0 storage eventually, but it's hard to say at this point how much it will actually matter.

[Chris Pratt]

45 minutes ago, cacoe said:

Hard to say whether there will be a difference in gaming performance at this point because we have nothing to test yet. Gen4 provides faster sustained reads and writes, there's currently not nearly as much gain on random reads or writes though which is probably what is going to make the biggest difference. 

 

That all said, I think you're better getting a good nvme gen 3 drive rather than a bad nvme gen 4 drive.

 

(see my specs, my gen 3 drive is faster than my gen 4, thinking about changing the boot drive for something else)

That's probably mostly a factor of it being such a small capacity SSD. There's likely only a single chip of NAND flash on that drive, so no ability to parallel. 500GB-1TB is the sweet spot for SSD performance.

[LAwLz]

7 hours ago, steakrocks123 said:

I'm not sure it it will actually be worth it spending the extra money to have the drives be pci gen 4. From what I've been able to tell, it's about double the raw performance per drive to go to gen 4.0 instead of gen 3.0 (2GB/s per lane vs. 1GB/s per lane). Would there be any point to going gen 4 vs gen 3 assuming my setup has the lanes to support them?

Maybe I am misinterpreting your post, but it sounds like you think PCIe generation is what determines the speed of an SSD. It's easy to assume that's how it is, but it's wrong.

The PCIe bandwidth is the theoretical maximum the connector supports. The drive you plug in might not be anywhere close to saturating the connector.

 

Think of it like this, the PCIe generation and number of lanes is the speed limit of a road. Driving on a 200mph road won't make a little Fiat Punto any faster than if the speed limit was 150mph, because it will probably never reach any of those speeds anyway.

 

As @cacoe said earlier in the thread, there are PCIe gen 3 drives that are faster than PCIe gen 4 drives.

What matters is the quality of the drive, not the PCIe version it uses.

 

Here is a comparison of the Samsung 750 Evo vs the 850 Pro. Both of them use the same interface standard (SATA 3, which is rated for 6Gbps).

In that particular test, the 850 Pro is over 60% faster despite both of them using the same interface.