Can gamma rays affect ground-based computers?

I work on software for a living. At my company, everytime we do an FMEA, someone always brings up the whole “what if a gamma ray flips a random bit?”, in an argument to support needed robustness in the system.

Yes, it is possible. But the rate is low. Ordinary PCs don’t have any error detection or correction, so a hit could cause a crash. But memory size has grown a lot over the years, and my suspicion is that cosmic rays now cause more crashes than thought.

But servers should have detection/correction for this reason and for others.

Cosmic rays increase a lot with altitude.

from a study by Google:
On average, about one in three Google servers experienced a correctable memory error each year and one in a hundred an uncorrectable error, an event that typically causes a crash.

wikipedia:
Error-correcting memory

DRAM memory may provide increased protection against soft errors by relying on error correcting codes. Such error-correcting memory, known as ECC or EDAC-protected memory, is particularly desirable for high fault-tolerant applications, such as servers, as well as deep-space applications due to increased radiation.

Error-correcting memory controllers traditionally use Hamming codes, although some use triple modular redundancy.

Interleaving allows distributing the effect of a single cosmic ray potentially upsetting multiple physically neighboring bits across multiple words by associating neighboring bits to different words. As long as a single event upset (SEU) does not exceed the error threshold (e.g., a single error) in any particular word between accesses, it can be corrected (e.g., by a single-bit error correcting code), and the illusion of an error-free memory system may be maintained.

.

Aras Innovator PLM Software – FMEA Demo