RAMAC Park and the Origin of the Disk Drive

Did you know that there is a park in San Jose named after a disk drive? Actually, technically it is named after the first computer that used disk drives. You couldn't just go and buy a disk drive peripheral on its own. We're talking about 1955.

I actually found out about RAMAC Park's existence long before I actually went there and took a few photographs. Before I rejoined Cadence, I was working for SemiWiki and I interviewed Gary Patton, who was the CTO of GLOBALFOUNDRIES. He is currently GM of Design Enablement at Intel. You can still read that original piece in SemiWiki titled How GlobalFoundries’ CTO Nearly Became a Lawyer…Called Funkhauser.

IBM's Cottle Road Site

Relevant for this piece is that he worked for IBM for years in the era when employees would joke that IBM stood for "I've Been Moved" since they operated a little like the military and moved people around a lot, especially anyone who seemed likely to rise through the ranks. I know the feeling since my father was an officer in the Royal Navy, so I'm what in the US is called a "navy brat" although I don't know of an equivalent phrase in Britain. When Gary decided to switch from being purely technical to management, he was sent to San Jose to work in the management of IBM's disk drive manufacturing facility on Cottle Road in San Jose. Eventually, IBM got out of that business by selling it to Hitachi and gradually the large campus closed. Some of it is still there, although it is surrounded by a high fence to keep you out of the empty parking lots. The buildings are like nothing in Silicon Valley today, more like some buildings escaped out of an Austin Powers movie...they are "really groovy".

Here it was in its heyday:

Here's a picture I took of some of what's left of it looking sad:

Gary told me that he had heard that part of the campus had been turned into a park named after the original product that the campus was created to manufacture. Indeed there is. That's the park sign at the start of this post.

IBM 305 RAMAC

The IBM 305 RAMAC was the first computer system with moving head disk drives. It was announced in 1956, although there were already what we would call beta sites up and running by then. It was built with vacuum tubes, one of the last before IBM switched to transistors.

RAMAC stood for Random Access Method of Accounting and Control since its design was motivated by real-time business accounting. In that era, IBM only leased machines and didn't sell them, which would eventually result in an anti-trust lawsuit decades later, but that's a story for another day. They also got hit with an anti-trust lawsuit over their large market share in...typewriters. Good job the US government got that one sorted out or we'd have no choice in what typewriters we have to choose from today. A 305 RAMAC leased for $3,200 per month. Mr Google tells me that is $31K per month in inflation-adjusted dollars.

They have a RAMAC disk in the Computer History Museum (currently closed to visitors, of course). Here's a picture I took of that unit. It's hard to get a sense of scale at a glance, but notice the normal-sized electrical double switch to the left of the unit. The disks are two feet across.

The obvious question as a technologist is what the capacity of the drive was. There would be later improved versions, but the original specifications were:

• 5 megabytes total capacity, although the word "byte" had not yet been invented so IBM says "5 million alphanumeric characters"
• 50 24" disks giving 100 recording surfaces spinning at 1200 rpm
• Two independent disk heads, or "access arms" in the terminology of the time--they didn't have one head per disk surface, the two access arms moved up to select a disk, and then inwards to select a track, one arm selected the "down" surface and one arm could select the "up" surface
• Average access time was 600 milliseconds (0.6 seconds)
• Data transfer rate was 8.8KB/s
• It weighed over a ton

You might assume that this disk drive was just for storage and that it had a RAM of some sort to go with it. But it had a magnetic drum memory where the instructions were held, rotating at 6,000 rpm, which held 3.2K bytes. A typical instruction took 30ms, three revolutions of the drum (what today we would call instruction fetch, operand fetch, writeback). But some were slower. Divide took 10 to 37 revolutions.

The Disk Drive Patent

Since IBM refers to the "up" and "down" surfaces, and the unit in the CHM is vertical, I assume that was the way it was used. But the original disk drive patent shows it horizontal. I'm guessing IBM switched because that eliminates gravity from the mechanics. For much the same reason, we switched from horizontal to vertical furnaces for diffusion in semiconductor processing when we went from 8" to 12" wafers.

Here's the picture from that original patent showing the head mechanism:

If you want to see this fascinating historical document, essentially the fundamental patent on the disk drive, it is US patent 3,503,060. Ignore the date on the top right, that is just when this continuation was filed. If you look at the block of text at the start of the patent itself, you can see it was originally filed in 1954.

Moore's Law and Disk Drives

DIsk drives didn't seem to have a high-profile individual in the same way as Gordon Moore set the roadmap for semiconductors for decades without really intending to, and "Moore's Law" became something that you might even read about in the mainstream press. Of course, disk drive controllers have benefited from advances in semiconductors. But the density of recording magnetic drives went up even faster than Moore's Law for completely different reasons. Without those advances, we risked having PCs just as we did, starting in the 1980s, but without any hard disks (and don't forget, none of the Apple II, the first Mac, nor the first PC had hard disks). How about a 3GHz PC with floppies. Or with a hard disk weighing hundreds of pounds. But, in fact, you can buy a 1TB hard drive for $44.99 today.

Of course, the future is solid-state drives (SSDs) based on 3D flash and it remains to be seen whether and in what form rotating media survives in the long run.

To put terabytes in perspective, RAMAC disks were 5MB, weighed a ton, and had to be delivered with a forklift. A million times bigger would be 5TB, just a bit bigger than the drives you can buy online with the click of a button, shipped to you overnight in a small box.

Visiting

As I said, you can see a RAMAC disk at the Computer History Museum in Mountain View, assuming one day we are allowed to visit again. I recommend a visit (not just to see the RAMAC disk, of course). For a little more detail, see my post Computer History Museum History,

I can't honestly recommend a trip to IBM Cottle Road and RAMAC Park unless you really, really want to say you've been there. IBM is largely closed off, and the park is just like any other park except for the name. I didn't see anything that even explained what RAMAC was. But Google Maps knows just where it is if you decide to go. It's certainly a piece of Silicon Valley history, if you can count the most southern part of San Jose as still in Silicon Valley:

There's actually a story behind that Lowe's Home Improvement store there. That is on part of the old IBM campus. But there were moves afoot to list the buildings as some sort of site of historic interest. But here's the San Jose Mercury story from 2008, Fire guts San Jose’s historic IBM Building 25. So Lowe's got their permits to build. At least they built the new store in the style of the original IBM buildings, which are supposed to echo the punched cards of the era.

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