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A comment on The software that flies SpaceX rockets and starships. Parent comment

Re:The software that flies SpaceX rockets and starships by Beached on Wednesday December 29, 2021 @11:09AM (#29726086)
iirc all flight systems are in triplicate and all data is checked against the others, then a quarum is needed from the 3 to make a decision.

other rockets use rad hardened computers that make decisions on their own, but for cost and time, I believe SpaceX just triplicated all necessary systems and votes out and reboots any system that gets bit flips.

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Re:The software that flies SpaceX rockets and starships by bodhiandpysics1 on Wednesday December 29, 2021 @01:57PM (#29728460)
They actually use more than three now. The basic architecture is that computers are organized in "strings". Each string is doubled. If the two don't agree, the result is chucked, and the system reboots. Each of these "strings" then participates in a quorum. The result is extreme reliability, with relatively fast convergence.
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Re:The software that flies SpaceX rockets and starships by wikibob on Wednesday December 29, 2021 @02:14PM (#29728734)
Fascinating. Could you write more about this, or do you have suggestions for what to read to learn more?
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Re:The software that flies SpaceX rockets and starships by lnsru on Wednesday December 29, 2021 @03:32PM (#29729626)
Functional safety standards like ISO 61508. But I am not sure if you will like it.
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