Microsoft veteran's worst Windows bug was Pinball running at 5,000 FPS
- Reference: 1757402114
- News link: https://www.theregister.co.uk/2025/09/09/dave_plummers_worst_windows_bug/
- Source link:
Alongside Task Manager, the game is one of the Windows components for which Plummer is best known, even though Windows XP was the last client release to include it. He ported the original game to Windows NT, converting chunks of assembly into C. He wrote an engine around the original code to deal with video and sound, and that's where the problem lay.
"My game engine had a bug," Plummer admitted on his [1]Dave's Attic channel , "in that it would just draw frames as fast as it could."
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This wasn't much of an issue on the hardware of the day. Plummer was using a MIPS R4000 at the time, a mighty beast running at 200 MHz, but it became a problem as hardware improved.
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"If I was having a good day," recalled Plummer, "it would run at 60 to 90 frames per second. And I figured that's plenty for a game like that."
However, a few years later, one of Plummer's design choices made itself known. The game would hog an entire CPU core in order to draw its frames as fast as it possibly could. "It was now drawing at, like, 5,000 frames per second because machines were much, much faster."
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It was another veteran Microsoft engineer, Raymond Chen, who tracked down the bug. In an [6]interview on the Dave's Garage channel, Chen recalled locating the problem. Why was Pinball using so much CPU? "I realized it had no frame limiter", he said. "It just rendered frames as fast as it could."
Chen found some debug code to show the frame rate, which threw up three asterisks. Computers were now so fast that the frame rate exceeded three digits.
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Adding a frame rate limiter meant the CPU usage plummeted. Chen set it to 100 frames per second, and the CPU usage dropped to approximately one percent.
"My proudest moment in Windows development," said Chen, "was I fixed Pinball so you could kick off a build and play Pinball at the same time."
That said, Plummer also noted that having a bug in production code was never a laughing matter. "That was kind of a shameful thing," he said. If true, there must be plenty of shamefaced Microsoft engineers around these days, considering the quality of recent updates.
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A bug in the daily builds, though? Something that actually broke the build? "People were merciless," recalled Plummer. He remembered Windows legend Dave Cutler firing off a comment when some horrible code was checked in, suggesting that the author might have had a few adult beverages.
"It was all fun and games until you shipped it. And then it was really serious." ®
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[6] https://youtu.be/-vJQv4rgHYE?si=XmfHg5FYjzAfBIyU
[7] https://www.theregister.com/2025/04/23/when_microsoft_made_the_windows/
[8] https://www.theregister.com/2025/03/27/looking_back_at_windows_longhorn/
[9] https://www.theregister.com/2024/08/23/build_your_own_pdp11/
[10] https://www.theregister.com/2024/08/02/who_wrote_windows_bsod/
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[12] https://whitepapers.theregister.com/
Re: MS now ships worse bugs in minor KBs they don't even warn you about
New World (an MMO from 2021) initially (in the beta) had unlimited framerates in the menu screen. Some people reported damaged graphics cards from this. Blame was eventually laid at the card-manufacturer, but the developer still went ahead and put a limit on the framerate. Who really needs 9000fps on the menu screen?
https://en.wikipedia.org/wiki/New_World_(video_game)
Next week, an ex-microsoft programmer reveals the bugs in Windows 11.
Which turns out to be the entire codebase.
Especially the places where the comments are commented out.
So it's confirmed
He remembered Windows legend Dave Cutler firing off a comment when some horrible code was checked in, suggesting that the author might have had a few adult beverages.
The [1]Ballmer Peak is a real thing, then.
[1] https://xkcd.com/323
Full Tilt Pinball
Early 90s I had Full Tilt Pinball installed, and a mate really loved it. He really wanted those high scores, but I was just ahead (more game-time). One day I had to go on-site, so left him in the office. On my return there's a hand written note of joy and mockery "Check out that score bud!" It was _massive_, beyond comprehension! WTF? I knew the scores were kept in a plain text file, and although the guy had (and still has) not a clue about computery type stuff I checked for tampering. Nope, unsurprisingly. I couldn't figure it out. The next time he was around we were playing. I could see him trying not to do something, to not give away his secret, but he couldn't help himself and stuck the ball behind a bumper right on the edge of the table. It locked there, pinging madly across the one pixel gap between the bumper and the edge of the table: 1000; 10000; 1000000.... I can still see the giggling bastards face! :D
(Kids today and their electronic gizmos! I've still got my [1]bagatelle football game in the loft!)
[1] https://www.pinterest.com/pin/bagatelle-boards--538602436662177771/
MS now ships worse bugs in minor KBs they don't even warn you about
> That said, Plummer also noted that having a bug in production code was never a laughing matter. "That was kind of a shameful thing," he said. If true, there must be plenty of shamefaced Microsoft engineers around these days, considering the quality of recent updates.
Yeah, imagine an unlimited frame rate in a game you can close being the worst thing you ever shipped at MS - when now they've just got crapass outsourced vibe coders (okay the insourced ones are total crap too) randomly destroying swaths of SSDs for an update that wasn't even needed and the response is '*shrug YOLO* sucks to be you using Windows11!'
And wow, imagine a time when MS actually ran things by a QA dept instead of just shrugging and shitting them out all over hundreds of millions of systems. Wonder how he feels about the current complete shitshow - where the quality of updates is as like a Donald Trump product (because they're 1/3 written by LLM, and no QA), or if he's just like my old biggest MS defender in the world for 30 years friend who now mostly just refuses to talk about it because he's so disgusted by what Win11 (and XBox) have become.