i-RAM as a Paging Drive

One question that we've seen a lot is whether or not the i-RAM can be used to store your pagefile. Since the i-RAM behaves just like a regular hard drive, Windows has no problem using it to store your pagefile, so the "can you" part of that question is easily answered. The real question happens to be, "should you?"

We have heard arguments on both sides of the fence; some say that Windows inefficiently handles memory and inevitably pages to disk even when you have memory to spare, while others say that you'd be stupid to put your pagefile on an i-RAM rather than just add more memory to your system. So, which is it?

Unfortunately, this is the type of thing that's difficult to benchmark, but it is the type of thing that's pretty easy to explain if you just sit down and use the product. We set up a machine, very similar to how we would a personal system, but tended to focus on memory hogs - web pages with lots of Flash, Photoshop, etc. Of course, we opened them all up at once, switched between the applications, used them independently, simultaneously, basically whatever we could do to stress the system as it normally would be stressed.

At the same time, we monitored a number of things going on - mainly the size of the pagefile, the amount of system memory used, the frequency of disk accesses, pagefile usage per process... basically everything we could get our hands on through perfmon to give us an idea if Windows was swapping to disk or not.

The end result? There was no real tangible performance difference between putting more memory in the system and using the hard disk for the pagefile or putting less memory in the system and using the i-RAM for the pagefile. Granted, if we had a way of measuring the overall performance, it would have shown that we would be much better off with more memory in the system (it runs faster, and it is accessed much quicker than off the i-RAM).

The only benefit that we found to using the i-RAM to store our pagefile was if you happened to have a couple GBs of older DDR200 memory lying around; that memory would be useless as your main system memory in a modern machine, but it'd make a lot better of a pagefile than a mechanical hard disk.

One more situation we encountered that would benefit from storing your pagefile on the i-RAM was those seemingly random times when Windows swaps to disk for no reason. But for the most part, our system was slower when we had less memory and stored the swapfile in it than when we had more memory and less swap file.

Adobe Photoshop is a slightly different creature as it keeps a scratch disk that is separate from the Windows pagefile. We tested Photoshop and used the i-RAM as our scratch disk, but in all cases it always made more sense to just throw more memory at Photoshop to improve performance where we ran out of memory. If the operations you're performing in Photoshop can fit into system memory, then you'll never touch the scratch disk.

Overall, based on our testing, the i-RAM doesn't make much sense as a paging drive unless you have the spare memory. The problem with "spare" DDR200 memory is that it is most likely in small 64MB, 128MB or maybe 256MB sizes, which doesn't buy you much space on an i-RAM drive. For most people, you're much better off just tossing more memory in your system.

i-RAM Pure I/O Performance i-RAM as a boot drive
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  • pieq3dot14 - Tuesday, July 26, 2005 - link

    I'd like to see how this would change the overall latency of a system. I have a pretty nice home studio, and I can see using this as a boot drive, and then recording off to a raid array. With all the random accesses coming from the solid state drive, and only sequencial going to the raid, I'd think the latencies would drop significantly. Could be pretty handy, even extending the life of older systems. Reply
  • bwall04 - Tuesday, July 26, 2005 - link

    Anand, first of all great review, it's nice to see some numbers on this.
    Would it be possible to bench a few tests again with 2GB of system memory? I can vouch that 2GB makes a noticeable difference when loading any game. I realize that you were going for an "enthusiast" level machine but games like HL2, Doom3,and Battlefield 2 has started a push with the high end to upgrade to either 2x1GB or 4x512MB.
    Reply
  • racolvin - Tuesday, July 26, 2005 - link

    Could they perhaps have gone with a full-size card and then oriented the DIMM slots perpendicular to the mobo? I had something like that ages ago in an Amiga that worked well from a size perspective. It might get them to 8Gb :) Reply
  • somu - Tuesday, July 26, 2005 - link

    cost of this unit was increased 3 times.
    then it went from sata2 to sata.
    Real life performance is not as gd as i expected, when i first heard i was excited to see them working on removing the bottleneck but going from 13 second load time to 10 second doesnt warrant the cost of the 150 card and 4 gb ram.
    Reply
  • shaw - Tuesday, July 26, 2005 - link

    #1 4GB space = poop
    #2 Still bottlenecked by the SATA bus

    I just hope this is the beginning of a bright future, but for now I'm not impressed one bit.
    Reply
  • IvanAndreevich - Tuesday, July 26, 2005 - link

    How about a Raid0 test with 2 of these cards :) Reply
  • JNo - Tuesday, July 26, 2005 - link

    How about Read the Frickin Article? Reply
  • audiophi1e - Tuesday, July 26, 2005 - link

    I think the more useful implementation is to have the RAM pre-installed onto the drive. And I'm not talking RAM sticks. I'm talking about these guys at Gigabyte contacting Samsung, Micron, or Crucial to directly supply the chips and directly solder them onto 5.25" plates. I think in the space of a 5.25" bay, you can fit 2 of these said plates. It won't be hard to think that they'd be able to fit 15GB of RAM in a 5.25" drive's space.

    Then with the remaining space, mount a MUCH larger battery. Have the battery be able to last DAYS, not hours. This will set people a little more at ease. It will sure make me feel better. (and no, this 5.25" ramdrive will not be using a molex connector. Simply put in a dummy PCI card to allow the 5.25" to draw power from it)

    The fatal flaw in their product design is that most people simply won't have that many RAM sticks laying around to make this thing useful. Why not supply the RAM, and in the process increase the possible size from 4GB, to something much more useful. If we already know that only 'power users' with little budget restraints will buy this, then just supply it the way we know they want it: Big.
    Reply
  • Zebo - Tuesday, July 26, 2005 - link

    Yeah one really needs about 15-20G to make this a livable reality. And that would cost about 3K and about 4K if they did it right i.e. ultra SCSI or even PCIe interface. Reply
  • Sindar - Tuesday, July 26, 2005 - link

    If they got real serrious tunned it up with on pcb ddr3. Made it something like a ZIF socket thing. Gave it a direct bus to the chip, changed the memorie contoler to let it throtle wide open. Wrote drivers, OSes to just use it. It might be like a really fast bios set up for the OS. At first it could be like an extra, but as costs came down maybe it would be intergrated into the motherboard. Humm nearly alomst instant boot up...it's a dream, even if it's only mine! Reply

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