Computer memory and my memories

This morning our small group at church was chatting about how we had each spent the past week with our kids on spring break. One family had gone to Texas, and told about visiting NASA. Somehow that got us talking about the Apollo missions, and how the mainframe computers NASA used then would be considered very underpowered by today’s standards. “Less power than a pocket calculator,” someone said. “A digital camera has more memory,” another added. “My cell phone has more memory,” a third commented.

I’ve heard similar comparisons, but wondered just how true they were. So I did a little looking on the internet this evening. Certainly the low amount of memory compared to today’s devices is true. The IBM mainframes NASA used had a maximum capacity of 32K RAM, which couldn’t store even a single picture I take on my digital camera at the default size and resolution. In terms of speed they were comparable to a 1 MHz clock speed; today’s computers have speeds measured in GHz (one thousand times faster).

As someone who used to work for NASA explained, however, the comparison that matters is not the hardware specifications but the work that can get done on them.

For those used to waiting 15 seconds for a Windows spreadsheet to even load, it’s difficult to imagine how much work a 1MHz computer can do when it’s running full tilt in machine language, not encumbered by bloated software, interpreted languages, and a GUI interface. I’m old enough to remember, and look back on those days wistfully.

At other websites, I learned that the common comparison of the Apollo guidance computer to today’s kitchen appliance suffers from a similar misunderstanding. Like a kitchen appliance, the guidance computer was built for a specific purpose and only had to do that one thing well. It didn’t have to do any number-crunching – that was all done by the mainframes back at NASA, and only the results had to be communicated to the Apollo’s onboard computer.

Still, it’s remarkable how fast computers have changed. I can barely remember the Apollo missions (I watched the moon landing on TV and was young enough to be more bored than excited by it), so the knowledge that computer power has advanced exponentially since then is unsurprising. But then I read tonight on wikipedia that the Pentium microprocessor was released 16 years ago today. It was available in a speed of 60 MHz and 66 MHz.

Today you can easily buy a computer with a speed in excess of 3 GHz (approximately 3000 MHz), although with dual- or even quad-core architecture it’s hard to make the kind of clock speed comparisons that I’m used to. My younger son has a rather old computer (bought used a few years ago for $40) that is only 300 MHz. He can’t play the newest games, but he has a nice collection of games written for Windows 98 and Windows 2000 that run well. But I can’t think of a thing we have that could run on an original Pentium PC.

1993 wasn’t all that long ago. We were busy getting ready for my (older) son’s first birthday (at the time of course he was an only child). This week we’ll be celebrating his seventeenth birthday. I can’t say it seems like just yesterday we were watching him learn to walk, but it’s not a lifetime ago (well, it is to him). When I think back to the people I knew as good friends then, back when we lived in New Jersey, it doesn’t seem like that long ago and it surprises me to do the math and realize how many years it’s been.

Of course, I look at my son’s size 13 foot (or is it 14 now?) and realize he’s done an awful lot of growing since then too.