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Comment by stephencanon | Hacker News Reader

Unless I’m severely misremembering, Cortex-A8 had ECC support, and appeared ~6 years ago.

That may be correct, but I chose the word "platform" very carefully. Most ARM platforms to date, whether dev kits or final product have been aimed at smartphones, tablets, consumer devices (wireless routes, NAS etc) or fully embedded systems (SD cards?, hard disk controllers, etc). Apparently in those applications, nobody cares enough about ECC to bother.

Well, that and the fact that the memory is soldered on in most cases and the total device cost extremely low (compared to servers). So you are expected to simply replace your system entirely in the event that there are memory errors you notice. And hopefully nothing goes wrong that you don't notice.

Also, I suppose technically if you were only worried about bit flips due to solar activity, then a tiny amount of RAM on a tiny chip has less surface area and fewer bits TO flip than your standard full sized DIMM.

ECC doesn't typically yield that much of an advantage in the nominal case until you get into very large amounts of memory - it's just a more expensive part. I think it was calculated that cosmic rays are likely to cause single bit errors in systems of 8GB of memory only once a decade, and most embedded ARM situations (also carefully avoiding the "p" word) have far less than 8GB of memory. So if single-bit errors are causing your embedded device to crash, it's okay, it'll just roll over and restart... once every 50 years...

How about in a datacenter with 1000 processors and 64 gigs of ram per processor?

There haven't really been any usable ARM server chips. There was supposed to be the Armada XP, but by the time it came out it was obsolete. There was supposed to be Calxeda but they went out of business. Maybe the nth time's the charm.

AMD has the size such that making it happen may be easier for them. But they are also hungry for something, anything to give them an edge against Intel. Fingers crossed.

Boston Viridis ARM server supported ECC memory.

Too bad it wasn't competitively priced.

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