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My oldest code still running
» Home : Blog : November 2008
One of the odd things about working at Hewlett-Packard is that part of it is what's left of Digital Equipment, where I worked for seven years, from 1986 to 1993. Every once in a while, I'll stumble on some new artifact of that history. Lying next to a printer, I found this, a VMS banner page:
It took me back, because back in the late eighties, I worked on this software, meaning not just the printer software in VMS, but the PostScript code that drew this page.
This is probably the oldest software of mine still running. Funny to think that while I went off to pursue hundreds of other projects, this PostScript code was obediently drawing this simple page over and over for 20 years.
Back when we were first developing that banner page, it was being used on an LN03R, an 8 page-per-minute laser printer. People complained that the banner page was taking too long to print. I was given the job of toning down the PostScript complexity so that it would print more quickly. People felt like all those scalable fonts must be a bottleneck.
After doing a number of controlled experiments, and whittling down on the pages, it became clear that nothing was making it go faster. Finally I reduced the code to:
and the blank page took just as long to come out of the printer as the "fancy" banner page with all the different font sizes on it.
What I learned was: