4 ms·

>They're so rare, They are not rare, just because you don't detect them (consumer hardware) means nothing. >>study done by IBM in the 1990’s that referenced 1

by nix23 4y ago

>They're so rare, They are not rare, just because you don't detect them (consumer hardware) means nothing. >>study done by IBM in the 1990’s that referenced 1 cosmic ray bit flip per 256MB of memory per month https://blog.mozilla.org/data/2022/04/13/this-week-in-glean-what-flips-your-bit/ https://blog.mozilla.org/data/2022/04/13/this-week-in-glean-...

lioeters 4y ago
One cosmic-ray bit-flip per 256MB per month. Significantly more for computers on aircrafts at higher altitudes. I kinda wish I hadn't learned this fact, how fragile everything is. On the other hand, it makes me appreciate the importance of error tolerance and recovery. > Cosmic ray flux depends on altitude. Computers operated on top of mountains experience an order of magnitude higher rate of soft errors compared to sea level. The rate of upsets in aircraft may be more than 300 times the sea level upset rate. https://en.wikipedia.org/wiki/Soft_error#Cosmic_rays_creating_energetic_neutrons_and_protons https://en.wikipedia.org/wiki/Soft_error#Cosmic_rays_creatin...
- nix23 4y ago
  >One cosmic-ray bit-flip per 256MB per month. Significantly more for computers on aircrafts at higher altitudes. Yes thats why you have max altitude for normal servers/hardware and it's also more disastrous on modern HW -> smaller transistors.
- shadowgovt 4y ago
  The reason we all now wear our seatbelts through the entire flight is there was a cross-Pacific flight that had a sudden altitude drop where several people were injured from rebounding off the ceiling. When the news reported on it, they reported the cause was believed to have been an undetected massive downdraft that shoved the plane down. I lost the thread on that story before the investigation concluded the actual cause was autopilot error. It is, in some ways, more comforting to me to know that the issue wasn't novel atmospheric phenomena, but instead relatively-mundane cosmic radiation flipping one packet of data from the sensors to the avionics that the avionics lacked sufficient redundancy to detect or discard. As a result, the autopilot believed the plane had suddenly pitched 90 degrees and drastically corrected to escape stall.

by nix23 4y ago

lioeters 4y ago

One cosmic-ray bit-flip per 256MB per month. Significantly more for computers on aircrafts at higher altitudes. I kinda wish I hadn't learned this fact, how fragile everything is. On the other hand, it makes me appreciate the importance of error tolerance and recovery. > Cosmic ray flux depends on altitude. Computers operated on top of mountains experience an order of magnitude higher rate of soft errors compared to sea level. The rate of upsets in aircraft may be more than 300 times the sea level upset rate. https://en.wikipedia.org/wiki/Soft_error#Cosmic_rays_creating_energetic_neutrons_and_protons https://en.wikipedia.org/wiki/Soft_error#Cosmic_rays_creatin...

nix23 4y ago
>One cosmic-ray bit-flip per 256MB per month. Significantly more for computers on aircrafts at higher altitudes. Yes thats why you have max altitude for normal servers/hardware and it's also more disastrous on modern HW -> smaller transistors.
shadowgovt 4y ago
The reason we all now wear our seatbelts through the entire flight is there was a cross-Pacific flight that had a sudden altitude drop where several people were injured from rebounding off the ceiling. When the news reported on it, they reported the cause was believed to have been an undetected massive downdraft that shoved the plane down. I lost the thread on that story before the investigation concluded the actual cause was autopilot error. It is, in some ways, more comforting to me to know that the issue wasn't novel atmospheric phenomena, but instead relatively-mundane cosmic radiation flipping one packet of data from the sensors to the avionics that the avionics lacked sufficient redundancy to detect or discard. As a result, the autopilot believed the plane had suddenly pitched 90 degrees and drastically corrected to escape stall.