Pemalite said:
vivster said:
Yo, bros! I need a little bit of help here.
I think I can tackle most on this one
https://gamrconnect.vgchartz.com/post.php?id=9144439
But I'm a bit stumped on this one.
https://gamrconnect.vgchartz.com/post.php?id=9144445
The problem is I'm not too familiar with the exact data flow between storage, RAM and VRAM while playing a game. Using an SSD as RAM or VRAM sounds a bit silly to me. That thing about decompression in the GPU sounds plausible but it feels like something that would be done in hardware and as such wouldn't have much of a performance impact.
Does the VRAM even stream data directly from the storage? Seems like something I would load in RAM first based on predicting what I will need for the game. |
Memory storage typically goes from Largest(Cheapest per byte)+Slowest to the Smallest+Fastest. - This is because the fastest memories are damn expensive (I.E. L1/L2/L3 caches) so we can't make entire systems out of the stuff.
I.E. [Hard Drive/SSD, Terabytes @1-10GB/s Microseconds] ---> [RAM, Gigabytes @32-1024GB/s. Nanoseconds] ---> [Cache, Megabytes @ 200-2048GB/s. Nanoseconds]
So we hide that by having tiers of memory sizes and speeds in order to try and get around that issue efficiently... Then we implement various technologies like "branch prediction" so that we can predict the data ahead of time and move them up the memory hierarchy to reduce the impact of accessing slower memories even further.
There are instances where the data isn't going to be in VRAM or Caches and that data will be accessed from the base storage, but this is a last-resort.
We have actually be using hard drives for "Ram" going back a quarter of a century or more, it's actually not a new technology... Though it was called "Virtual Memory". - Or a "Swapfile" - And was used when a program/game wanted to reduce it's Ram consumption or when Ram became full... Otherwise you would get an out-of-memory error and a crash.
Now SSD's aren't doing anything new or differently here, the Swapfile/Virtual Memory still exists... But it's not going to be restricted to mechanical hard drive transfer rates or latencies so there is a big uptick in performance... However, it's still orders of magnitude slower than Ram and still has orders of magnitude inferior latency... Thus the need for Ram still exists and will continue to exist.
The one issue I have is that if developers next-gen start relying on the SSD as a "Scratch Pad" for memory transactions we will start to see allot of arbitrary writes to storage, which means that the NAND wear could be significant, which may potentially create reliability implications for the next-gen consoles... But that is just a hypothetical on my behalf, I am sure Sony and Microsoft have put allot of thought into that aspect and worked around it to various degrees.
So in short... Yes, SSD's can act as "Ram". - But you wouldn't want to replace Ram with it.
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Yeah, that's pretty much how I would've thought. Swap files aren't new to me, but I can't imagine that whatever the consoles are doing with their SSDs is gonna improve performance a lot.
The main feature that utilizes those SSDs will be the instant game resume, but we have had that sleepmode functionality on PCs with SSDs for a long time, just not for games. I find it hard to imagine a scenario where a game is specifically designed around SSD storage having a performance edge against traditionally designed games.
