[greenG4]

I was reading up on this and it seems like a pretty nice thing. Note this is not about SSDs (Solid Stste Disks). Billy is pushing for this because he wants it in Longhorn. Is this a posibility on OS X as well? It reads like it will be a windows-only thing.

[Hawkeye]

Originally Posted by greenG4

I was reading up on this and it seems like a pretty nice thing. Note this is not about SSDs (Solid Stste Disks). Billy is pushing for this because he wants it in Longhorn. Is this a posibility on OS X as well? It reads like it will be a windows-only thing.

Maybe it's just be, but I don't get it. Wouldn't it be cheaper and easier to just install more RAM? If you aren't paging to the HD you'll spin-up the drive less, right? They even mention that 64-bit processors/os/applications will be able to use up to 128GB or RAM. In addition to the above, can someone explain why this would be any better than just installing more RAM (and having your system use it more effectively).

[Dog Like Nature]

I guess the difference is this buffer is made of Flash memory, which means writing to this disk would be considered permanent even if the power is turned off immediately afterwards, and the platters have not been spun up.

If you simply add more volatile RAM, you run the risk of your data not getting synched to the disk if the power is interrupted.

Having said all that, the article talks about laptops, which should pay close attention to the power supply, and do cool things when it's about to run out...

[Hawkeye]

Originally Posted by Dog Like Nature

I guess the difference is this buffer is made of Flash memory, which means writing to this disk would be considered permanent even if the power is turned off immediately afterwards, and the platters have not been spun up.

If you simply add more volatile RAM, you run the risk of your data not getting synched to the disk if the power is interrupted.

Having said all that, the article talks about laptops, which should pay close attention to the power supply, and do cool things when it's about to run out...

Good call.

[Big Mac]

Originally Posted by Hawkeye

Maybe it's just be, but I don't get it. Wouldn't it be cheaper and easier to just install more RAM? If you aren't paging to the HD you'll spin-up the drive less, right? They even mention that 64-bit processors/os/applications will be able to use up to 128GB or RAM. In addition to the above, can someone explain why this would be any better than just installing more RAM (and having your system use it more effectively).

Yeah, you don't really get it. The point of this technology is to reduce the amount of time the drive is spinning, which would be a good thing for laptops and other portable devices. If you can afford to buy 10GBs of RAM, let alone ten times that amount or more, then more power to you. Dog Like Nature also brings up a great point about the unsuitability of DRAM as a hard drive replacement. The day technicians produce a significant, cost-reducing breakthrough in SRAM production or some other kind of solid state static memory, you'll be right. Until then, this combination drive technology is a cost feasible way to reduce mechanical activity.

[Hawkeye]

I understand the need to reduce HD access time; however, I still fail to see how using this 128MB buffer is going to solve the overall problem of why people's machines read and write to the HD so frequently -- insufficient RAM.

The article's discussion of RAM use is entirely irrelevant, apparently:

Longhorn will also minimize reading from the hard disk drive by storing more data, including application data, in main memory, he said. With 64-bit technology, Longhorn can support up to 128GB of main memory. A user could keep all of a PC's data in the main memory, Microsoft Windows chief Jim Allchin said in a recent interview. "Let's suppose you had 10GB of primary memory, probably everything that you do could fit in memory," he said.

What is this planning on doing?

You basically have a HD with a built-in flash drive for the paging file, right? What else are you going to use this buffer for? The article specificially talks about how Longhorn will store more data in main memory. It doesn't really say much about how it's going to allocate to this special buffer; besides, it's not like you're going to constantly be swapping applications into and out of that buffer -- I would think that would hit the HD more.

So, the buffer-swap works until you swap more than your 128MB and you're right back where you started, needing more RAM; because the computer is just going to have to hit the HD to swap the data out of flash memory. Most of Dell's laptops start with 256MB of RAM (and some share their RAM for graphics ), so I can see Windows users with large paging files might exceed 128MB paging files. (Right now my desktop at work has 384MB allocated to paging and it has 256MB RAM.)

Do you see what I'm saying? The only data-allocation the article discussed was how Longhorn was going to make better use of memory and how 64-bit would enable us all to have 128GB of RAM and never worry about hitting the HD again. What is this drive going to do?

[Big Mac]

The drive just has a small amount of static memory to reduce the amount of time the drive has to spin, just like the iPod. Whether its price : performance ratio justifies the extra expense remains to be seen. You're right that computer usage easily sucks up the paltry amount of flash RAM, but that does not mean it won't be useful. Otherwise, they would not be investing in it. I wonder if the OS can decide what data to place in flash RAM. If core system libraries could be loaded there, it would speed up the system and definitely regular drive access. On my iBook, for example, I can type away in Mariner Write after my drive has spun down, but if it has to access spell check dictionaries the drive spins back up.

[Hawkeye]

Well, we've all seen a lot of technology that isn't very effective and yet highly invested.

I agree that I'm sure it will be better, I'm just skeptical as to how much better. Will the cost:improvement outweigh the cost:improvement of just buying more RAM? They did say that the drive would be costlier. Also, how efficiently will the OS and applications make use of this technology? It's my understanding that most operating systems and applications could do better in their use of main memory, now we have to count on people appropraitely handling how they allocate to "hard drive memory".

I guess we'll all see.

As for the original post, I can't imagine that the Mac OS couldn't be written to take advantage of it.

[Apfhex]

Just make the whole drive out of MRAM! (I know, not gonna happen)

[ghporter]

Hard drives use a lot more power than a comparable-sized amount of flash memory. A WHOLE LOT MORE. Flash memory, on the other hand, is a lot more expensive per gigabyte than hard drive space, but not a whole lot more. A solid state drive could conceiveably cut power usage enough to double a laptop's battery life (six to ten hours for an iBook? Yeah!) as well as reducing both weight and bulk. It is a Good Idea in a lot of ways. The question is whether or not it's "ready for prime time" yet.

[Millennium]

I'm skeptical of these, particularly if they're using flash. The basic concept is sound, but using flash memory for this is a Very Bad Idea.

There are two problems with this, both stemming from the use of flash. First, of course, is the problem that flash memory is relatively slow compared to hard drives. Although there would be a theoretical speed boost from consolidating many small writes into a single large write, odds are that the slow performance of the flash memory will negate that boost.

More worrrisome, however, is the relatively short lifetime of flash memory. Most flash-based drives nowadays can go for some 10,000-100,000 write operations. That's fine for removable storage, but even under average use a hard drive can get many more than 10,000 writes than that in just a year. Keep in mind that the flash memory would be getting writes at the same rate that the hard drive otherwise would, and you have a very short-lived technology indeed. Perhaps they will find some way to make the flash module replaceable, which would offset this somewhat, but otherwise this would be a colossal waste of a good hard drive.

Bottom line: they need some other kind of buffer technology, something that can support at least a million writes (and 10,000,000 would be better). If they can find technology like that, then the rest of the idea is just crazy enough to work. But flash memory as we currently know it just plain isn't going to cut it.

[Big Mac]

Originally Posted by Millennium

More worrrisome, however, is the relatively short lifetime of flash memory. Most flash-based drives nowadays can go for some 10,000-100,000 write operations. That's fine for removable storage, but even under average use a hard drive can get many more than 10,000 writes than that in just a year. Keep in mind that the flash memory would be getting writes at the same rate that the hard drive otherwise would, and you have a very short-lived technology indeed. Perhaps they will find some way to make the flash module replaceable, which would offset this somewhat, but otherwise this would be a colossal waste of a good hard drive.

Bottom line: they need some other kind of buffer technology, something that can support at least a million writes (and 10,000,000 would be better). If they can find technology like that, then the rest of the idea is just crazy enough to work. But flash memory as we currently know it just plain isn't going to cut it.

I didn't consider the short lifespan of flash memory. Would higher quality flash allow more read/write cycles? What makes the memory degrade in that fashion?