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RAM Doubler

The software hit of Macworld SF was definitely Connectix's RAM Doubler. Roy McDonald, Connectix's president, said that they sold about 3,000 copies at the show, and about another 3,000 through normal channels. Considering that RAM Doubler shipped the day of the show, that's not too shabby. But I digress.

You can never have enough hard drive space or RAM. Hard drives aren't all that expensive per megabyte though, whereas RAM is way up there, due in large part to the DRAM hoax of last year. You probably remember, the Sumitomo resin factory blew up, so prices on RAM reacted like commodity prices and skyrocketed. Like commodities, the prices were based almost purely on speculation, and as it turned out, a survey of existing stocks of the resin showed that the industry had almost twice as much of the stuff stockpiled as it was going to need by last December, when the plant came back on line. In essence, then, there was no reason for those RAM prices to rise, but rise they did. In fact, the dealers we users buy from probably made no more money on RAM than they normally do, but being almost at the top of the RAM food chain, they had no choice but to raise consumer prices. But I digress again - now that we're all irritated at the RAM manufacturers, let me explain what RAM Doubler is and why you're likely to want a copy.

RAM Doubler is a single small extension that literally doubles your RAM. It's not guessing at a 2:1 compression ratio, like Salient's AutoDoubler and DiskDoubler (now owned by Symantec) - you actually see your total memory being twice your built-in memory. Since RAM Doubler is an extension, there are no controls, no configuration. You just install it and it doubles the amount of application RAM you have available.

A number of people have expressed disbelief that such a feat is possible, saying that they'd avoid anything like RAM Doubler because it's obviously doing strange things to memory, which isn't safe. The answer to these naysayers is that a program like RAM Doubler either works or it doesn't - it's a binary decision. Since Connectix offers a 30-day money-back guarantee, you have nothing to lose if it doesn't work, and since there's almost nothing you can do to prevent RAM Doubler from working (remember, there's no configuration), it's an easy test. Tonya and I have both installed RAM Doubler to test it in low and high memory situations since her Duo 230 has only 4 MB of real RAM whereas my 660AV sports 20 MB.

Needless to say, since RAM Doubler has only been out for a few days, we haven't been testing for long, but I can honestly say that neither of us have noticed anything out of the ordinary during this time. In addition, Roy said that he has been watching the nets for complaints and has seen essentially none. This isn't to imply that RAM Doubler must be entirely bug free; in fact, there's a known conflict with 4D that will be fixed in 1.0.1, due out in a week or so. ACIUS has apparently released a patch for some other problem that also solves the incompatibility with RAM Doubler, but if you use 4D, I'd recommend waiting for a short while.

On our machines, though, RAM Doubler has performed perfectly. Tonya runs a relatively slim system and only a few applications like Word 5.1a, the Random House Webster's dictionary, and Eudora, whereas I have over two rows of extensions on a 16" monitor and a slew of applications, fourteen of which start up at boot time. To stress the system a bit, I launched Retrospect (4 MB of RAM), FreeHand, PageMaker, and Elastic Reality (a high-end morphing program from ASDG that likes 12 MB of RAM), and I still had about 6 MB free, so I started up speech recognition and switched to a larger uncompressed voice. Everything worked fine, although as I started to push the boundaries of my 40 MB, the Mac slowed down a bit.

In normal usage, Connectix estimates a two to four percent slowdown, although most people don't notice such a small speed hit, in large part because other extensions can easily reduce your Mac's performance that much as well. The speed hit will change slightly as you use more of the RAM that RAM Doubler provides since it must switch to more complex methods of providing the RAM it has promised to you.

I'm no programmer, so I can't tell you exactly how RAM Doubler works its magic, but the basic idea is that it uses Connectix's virtual memory technology to divert memory not to a disk file, but to other locations in RAM. There are several techniques involved, depending on the current RAM situation. RAM Doubler starts out by using the "empty" space in the About this Macintosh memory bars, which is the memory that an application has reserved but not used. After that, it pokes around for holes in the "used" space in those memory bars, or memory that the application has used but won't again. Normally such memory is completely lost to other applications because applications generally require a contiguous block of RAM. If you keep launching programs, RAM Doubler will compress some of the contents of RAM using standard data compression techniques, and finally, if all else fails, it will swap some of the contents of memory out to disk, although I gather this primarily happens on Macs with less than 8 MB of real RAM.

Because of these techniques, you can't run other memory management tools, such as Apple's VM or Connectix's Virtual. In addition, you should not use RAM Doubler to run a single RAM hog like Photoshop - the speed hit will be hard and instantaneous since most of RAM Doubler's tricks fail when using only a single application. However, if you have 20 MB and wish to run Photoshop in 20 MB, you should be able to effectively use the additional 20 MB that RAM Doubler provides for other, smaller applications.

The more I think about RAM Doubler, the more I'm impressed by how simple and clever it is. The best analogy I can come up with is that of a hard disk. You don't need contiguous space on a hard disk to save a file - the Mac can track the different blocks that store various parts of a large file. Until RAM Doubler, RAM was the exact opposite, but with RAM Doubler, memory now works more like a hard disk so you can use every little bit that's free.

Of course, such a feat isn't easy, and the only way RAM Doubler achieves it is to use the MMU, or memory management unit, that's built into the 68030 and 68040 processors and keeps track of the entire contents of RAM. Thus, if your Mac has a 68000 or 68020 (with the exception of some 68030-accelerated Mac II's - ask Connectix for details), RAM Doubler won't work. Those of you on older Macs like the Plus and LC have another option, though, OptiMem from Jump Development Group. I'll talk more about it in a future issue.

The best testament to RAM Doubler's simplicity is its nine-page manual, with three pages that introduce RAM Doubler and talk about installing and removing it, four pages that answer common questions, and two pages that discuss Connectix's other products.

Overall then, RAM Doubler is a no-brainer. You buy it (it lists for $99, sold for $49 at the show, and I suspect that Connectix has lower than list prices for online users and for users of other Connectix products), install it, and poof, you have twice as much RAM available for applications.

If we're lucky, RAM Doubler will prompt a lowering of RAM prices as well, since only people who need tons of real RAM (like Photoshop users) should pay for real RAM. It's an easy decision, since if you have 8 MB of real RAM now, RAM Doubler costs somewhere around $50 and an 8 MB SIMM costs around $300. For people like me, it's even more worthwhile since RAM Doubler still costs $50 to up my RAM from 20 MB to 40 MB, but another 20 MB of SIMMs would probably run $750 or so. In other words, if you're starting to feel the RAM crunch, get RAM Doubler. It doesn't prevent you from getting more RAM later - it will double that just as happily - but for the moment it's the best deal going.

Connectix -- 800/950-5880 -- 415/571-5100 -- 415/571-5195 (fax)


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