DRAM SSD's

[fruit bat]

where can I find a list with DRAM based SSD products?
and if there's no such thing, then how can I figure it out if a SSD I want to buy has DRAM or no..?!

[AbedsBrother]

Początkowo opublikowane przez Bad 💀 Motha:

Ssds do not have any dram cache like a hdd does. Why? Because ssds do not need that and also an ssd has hidden built in extra nand for over-provisioning.

Look at WD, Crucial, Samsung...

DDR2 is approx 16gbps if iirc

Most SSDs do have a dram cache - like the Crucial MX 500, Adata SU800 or the Patriot Burst series (and others).

Cheaper SSDs (by cheap, I mean like the Crucial BX series or the Adata SU650) frequently don't have a dram cache - and in the past have demonstrated less longevity and slower read / write speeds over time. Afaik this is still the case.

[TehSpoopyKitteh]

Początkowo opublikowane przez 「 Mister .M. 」:

Początkowo opublikowane przez Omega:

DRAM based SSDs don't exist

completly wrong!
Kingston A400 is Dram based while ADATA SU650 (for example) is not.

It does exist....

Początkowo opublikowane przez q|O_O|p:

where can I find a list with DRAM based SSD products?
and if there's no such thing, then how can I figure it out if a SSD I want to buy has DRAM or no..?!

https://en.wikipedia.org/wiki/I-RAM

The Gigabyte I-RAM is an example of RAM based SSD’s. The concept has actually been around for decades. It’s highly impractical because it relies on having a power source 24/7 to operate. The I-RAM had an optional 16hour battery life that came with it, but if that battery dies, say goodbye to whatever software you installed on the device.

[Omega]

Początkowo opublikowane przez TehSpoopyKitteh:

Początkowo opublikowane przez 「 Mister .M. 」:

completly wrong!
Kingston A400 is Dram based while ADATA SU650 (for example) is not.

It does exist....

Początkowo opublikowane przez q|O_O|p:

where can I find a list with DRAM based SSD products?
and if there's no such thing, then how can I figure it out if a SSD I want to buy has DRAM or no..?!

https://en.wikipedia.org/wiki/I-RAM

The Gigabyte I-RAM is an example of RAM based SSD’s. The concept has actually been around for decades. It’s highly impractical because it relies on having a power source 24/7 to operate. The I-RAM had an optional 16hour battery life that came with it, but if that battery dies, say goodbye to whatever software you installed on the device.

I know they exist and it's nothing like an actual SSD. It's irrelevant when talking about modern hardware.

[L37]

Początkowo opublikowane przez Bad 💀 Motha:

Why would any ssd need dram cache buffer, that doesn't even make sense and would bottleneck the entire ssd IO

Every SSD, even usb flash drives and sd cards have some amount of RAM.
Mainly because SSD is essentially a computer, with its own OS and such, which needs RAM to run and store different stuff that needs to be accessed fast like lookup tables. It also does cache writes, because RAM is still at least 100-1000x faster than NAND.
A lot of people really underestimate complexity of SSD-s (or even simple sd cards)...

[Omega]

Początkowo opublikowane przez L37:

Początkowo opublikowane przez Bad 💀 Motha:

Why would any ssd need dram cache buffer, that doesn't even make sense and would bottleneck the entire ssd IO

Every SSD, even usb flash drives and sd cards have some amount of RAM.
Mainly because SSD is essentially a computer, with its own OS and such, which needs RAM to run, store different stuff that needs to be accessed fast like lookup tables. It also does cache writes, because RAM is still like 100-1000x faster than NAND.
A lot of people really underestimate complexity of SSD-s...

I wouldn't count a few bytes/kilobytes of on-chip temporary storage for use by the firmware as system RAM. It's just expected to be there and shouldn't affect the question if a device has a form of RAM or not. When applying this logic the motherboard also has RAM, and so does the ethernet card etc.. it overcomplicates everything and causes a ton of unnecessary confusion when someone is asking as simple question.

Let's say that any non-volatile storage which can be interacted with from within user space is memory. If there is anything wrong with my attempt at defining system memory then correct me.

[L37]

Początkowo opublikowane przez Omega:

I wouldn't count a few bytes/kilobytes of on-chip temporary storage for use by the firmware as system RAM. It's just expected to be there and shouldn't affect the question if a device has a form of RAM or not. When applying this logic the motherboard also has RAM, and so does the ethernet card etc.. it overcomplicates everything and causes a ton of unnecessary confusion when someone is asking as simple question.

Let's say that any non-volatile storage which can be interacted with from within user space is memory. If there is anything wrong with my attempt at defining system memory then correct me.

And a toaster... yes you are right.
But then do any SSD or HDD exist that has RAM that is accessible from outside the device? I bet it does not, but it also does not stop some manufacturers from advertising how much RAM their SSD or HDD has. And i think this is what got OP confused.

In another words i would answer original question like this:
Every SSD has RAM, varying amounts depending on specific device, but it does not matter for end-user and is not a thing you need to worry about when bying SSD.

[AbedsBrother]

Początkowo opublikowane przez Omega:

Początkowo opublikowane przez L37:

Every SSD, even usb flash drives and sd cards have some amount of RAM.
Mainly because SSD is essentially a computer, with its own OS and such, which needs RAM to run, store different stuff that needs to be accessed fast like lookup tables. It also does cache writes, because RAM is still like 100-1000x faster than NAND.
A lot of people really underestimate complexity of SSD-s...

I wouldn't count a few bytes/kilobytes of on-chip temporary storage for use by the firmware as system RAM. It's just expected to be there and shouldn't affect the question if a device has a form of RAM or not. When applying this logic the motherboard also has RAM, and so does the ethernet card etc.. it overcomplicates everything and causes a ton of unnecessary confusion when someone is asking as simple question.

Let's say that any non-volatile storage which can be interacted with from within user space is memory. If there is anything wrong with my attempt at defining system memory then correct me.

Not an LTT fan, but Linus made a decent explanation. (This video is from almost 2 years ago.)
https://youtu.be/ybIXsrLCgdM

LTT followed up a year ago.
https://youtu.be/v7YBCynA-b0

[TehSpoopyKitteh]

Początkowo opublikowane przez Omega:

Początkowo opublikowane przez TehSpoopyKitteh:

It does exist....






https://en.wikipedia.org/wiki/I-RAM

The Gigabyte I-RAM is an example of RAM based SSD’s. The concept has actually been around for decades. It’s highly impractical because it relies on having a power source 24/7 to operate. The I-RAM had an optional 16hour battery life that came with it, but if that battery dies, say goodbye to whatever software you installed on the device.

I know they exist and it's nothing like an actual SSD. It's irrelevant when talking about modern hardware.

Doesn’t matter. OP asked if any existed. Closest thing we have to it now is Intel’s Optane platform.

You said they don’t exist:
https://steamcommunity.com/discussions/forum/11/3356799628310715659/#c3356799628310748834

More specifically you said they are not considered solid state drives when in fact they really are. Early (1970’s and 1980’s) solid state drives used RAM chips as storage and they also required a constant power source.

[Bad 💀 Motha]

Yea I dont think OP was referring to SSD with dram cache buffer.

But overall I guess I also didn't see any point to this conversation. Just buy a ssd model that has a good track record.

[Astro_80 (WASH YOUR HANDS!)]

Początkowo opublikowane przez Omega:

DRAM based SSDs don't exist. The reason being that DRAM is volatile, this means that the data is lost when the DRAM isn't powered.

SSDs use NAND flash memory which retains the data even when not powered.

Some SSDs do have a small DRAM cache. This is refered to as "cache" in the spec sheet.

Ever heard of RAMDISK? No? Google it.

[Bad 💀 Motha]

That's ramdisk. Not an ssd.

[x_wing]

The nearest thing to what OP wants is probably intel optane memory.

Anyway, I never heard of DRAM based SSD. I don't think it is impossible, but can't think on a purpose for that either.

[nullable]

Początkowo opublikowane przez Bad 💀 Motha:

Why would any ssd need dram cache buffer, that doesn't even make sense and would bottleneck the entire ssd IO

Only if you don't understand that RAM is way faster than NAND...

Początkowo opublikowane przez Bad 💀 Motha:

Yea I dont think OP was referring to SSD with dram cache buffer.

But overall I guess I also didn't see any point to this conversation. Just buy a ssd model that has a good track record.

I don't think OP has a clear understanding of the terminology so asked a question that he thought made sense. I am guessing he's asking about standard SSDs vs DRAMless SSDs and sounds like he wants to avoid DRAMless SSDs because there are some small performance consequences. Upside is they tend to be cheaper (or that was the original plan) but they are still way faster than HDDs.

Początkowo opublikowane przez q|O_O|p:

Początkowo opublikowane przez Brockenstein:

Many SSDs have DRAM for caching. Some low end/entry level SSDs are DRAMless. "DRAM based" I think is you misunderstanding some terminology.

If it's not DRAMless then it has a DRAM cache. Not sure why so many people are complicating things.

ok and how do I know if a SSD I wanna buy is dramless or not?

Well you'll have to do your research. Depending on the particulars of the store page it may list those details explicitly. And if they don't, and you want to know for sure you'd need to refer back to the manufacturer's product page on their website to get the full details. Optionally a product review/benchmark may cover this as well.

[Bad 💀 Motha]

System ram IS much faster then any ssd, even an ssd based on pcie 4.0 but a dram buffer cache onboard a drive is a different story.

[nullable]

Początkowo opublikowane przez Bad 💀 Motha:

System ram IS much faster then any ssd, even an ssd based on pcie 4.0 but a dram buffer cache onboard a drive is a different story.

Well I don't need to argue with you. It's a pretty common feature on SSDs, whether you understand it or not. Even inside a SSD RAM is faster than NAND. And you're gonna have a hard time arguing otherwise. But good luck.