Slashdot Mirror
Computer Failure Causes Gridlock In MD County
Uncle Rummy writes "A central traffic control computer in Montgomery County, Maryland failed early Wednesday morning, leading to widespread gridlock across the entire county. The computer, which dates to the 1970s, is the single point of unified control for all traffic signals in the county, which comprises a number of major Washington DC-area suburban communities. When the system failed, it caused all signals to default to stand-alone operation, rather than the highly-tuned synchronization that usually serves to facilitate traffic flow during rush hours. The resulting chaos is a yet another stark reminder of how much modern civilization relies on behind-the-scenes automation to deliver and control basic services and infrastructure. The system remains down Thursday, with no ETA in sight."
That wouldn't make it any better.
I haven't read the article, but if the summary correctly reflects the situation, the traffic lights are all working - they're just working independently, so rather than being in sync so the main flow of traffic never has to stop (or stops less) they're all just doing their own thing.
The preferred solution is to not have a problem.
According to this it was a Data General main frame from the 1980s and not from the 1970s. Anyone know what model?
I live here too and it was mayhem last night. It took me 2.5 hours to get home from work which usually takes 25 minutes. (6 miles) Many of my coworkers and friends have also reported major headaches... We were sitting at traffic lights with nowhere to go for sometimes up to 5 cycles of the lights. What I heard is that there is a different timing for rush hours that lets more traffic flow south in the morning and north in the evenings. The worst areas according to news reports are Rockville Pike, which I experienced last night, Connecticut Ave, Georgia Ave and Rt 29. The official word is that some board blew in the main computer and they are unable to find "parts" to replace it. I am not certain about the details. The county website is reporting that all traffic lights are going to have to be manually updated one-by-one. There are 800 intersections.
Damn! 70s? Talk about Return on Investment.
The WashPost, in another article touts Fragile Technology.
I reach for my 70's era calculator and estimate the operational life of 34 years for this system. Some Fragility. Who or what at the Post has been there that long.
Wonder if its some ancient PDP version or an small IBM mainframe. The article is scarce on details. Parts for either are getting hard to find except in the scrap market.
Still you have to wonder why it wasn't ported to some other platform if nothing else as an exercise in disaster preparedness. Any commodity computer could do the job.
There is a lot of stuff like this still in service. I saw a PDP 8 monitoring turbines in a hydro Power station, and asked about where they get that fixed. The reply was it never broke down, but they had stockpiled 6 replacements, tested each yearly, just because they realized how old it was. Nobody knows exactly what it does anymore.
Sig Battery depleted. Reverting to safe mode.
IANATE (I Am Not A Traffic Engineer), but I've had the opportunity to talk to some over the years. From what I recall of those conversations, most, if not all, traffic signals are failsafe. They cannot have colliding greens, and they won't generally just turn off. Even in the event of a power failure, they're suppose to stay up on batteries for a while.
I have seen their failsafe behavior fail though. I was once driving on a dark foggy night. Visibility was very very poor. I was staying in my lane, but I couldn't see much else. I had a long drive in a rural area, and I was coming into an urban area. I expected to see street lights and traffic lights, but there were none. As I was driving, another car shot across the road just ahead of me, missing me by just a few feet. He didn't see the traffic light that wasn't working either. I called the police, so they could station an officer there. Their response was "Are you crazy? No one can see at that intersection. He'll get hit." Hmmm, good logic. At least no one got killed there that night.
Serious? Seriousness is well above my pay grade.
The blue is from appraching the light too fast. You're aproximately going 20% the speed of light. SLOW DOWN.
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
if the summary correctly reflects the situation
Please mod parent funny.
... to mediate traffic instead of traffic signals, they wouldn't have needed the aging old single-point-of-failure computer in the first place, because roundabouts (a) require no computers, (b) require no electronics at all, (c) require no electricity, and (d) don't require maintenance. What's more, since they allow motorists to preserve some momentum in all but the most congested traffic, gas consumption from forced arbitrary deceleration and acceleration is reduced. The only intelligence they require isn't of the artificial sort at all, only a smidgen of it from the motorists using them. They are un-powered and self-adjusting to traffic flow.
Would anyone like to take a stab at how much energy and man-hours is expended on the traffic signal network in the United States every year?
A meter maid has no more information about traffic flow at adjacent intersections than an autonomous single light would.
Then how about a Beowulf cluster of meter maids? (with walkie talkies of course)
call me FOSS im the boss with the sauce and the source
Bringing in Bruce Willis is *never* a bad idea. Need an asteroid destroyed in an affront to basic science? Call Willis. Need to remove an East German terrorist that can't speak proper German? Willis. Need someone to have sex with a hot, orange haired diety? Willis. Need Chuck Norris' ass kicked? Willis. Cancer cure? Willis. Making a Jaws Sequel? Have Bruce Willis play the shark.
There are some people that if they don't know, you can't tell 'em.
Whoa there, no need for Willis for that one. I'll do it. And if she objects, tell her the next choice is Shatner.