The general strategy is to test the system to the point where any bug like that is an edge case, some weird input you didn’t expect. So every time you get that

The general strategy is to test the system to the point where any bug like that is an edge case, some weird input you didn’t expect. So every time you get that input you’ll still crash, but other transactions will continue normally. Hopefully that input is either due to a transitory glitch like a bit flipped in RAM, or a user who isn’t bored enough to keep submitting it, but either way the process isolation means all your other jobs can continue.