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A comment on Micron Introduces 128 GB DDR5-8000 RDIMMs with Monolithic 32 GB Die. Parent comment

Re:Micron Introduces 128 GB DDR5-8000 RDIMMs with Monolithic... by crotchfire on Monday November 13, 2023 @01:29PM (#38253422)
It's really that simple.

> the complexities of having ECC protection only on the link

That's not SECDED, since it can't correct a bitflip that occurs somewhere other than on the link, nor can it detect a double bitflip in those situations.

SECDED. Just ask for SECDED.

Even the Linux kernel knows about this:

   # cat /sys/devices/system/edac/mc/mc1/csrow3/edac_mode
   SECDED
SECDED. Just ask for SECDED.
[ Parent | on HN ]
Re:Micron Introduces 128 GB DDR5-8000 RDIMMs with Monolithic... by wtallis on Monday November 13, 2023 @02:17PM (#38254007)
> That's not SECDED, since it can't correct a bitflip that occurs somewhere other than on the link

You're just making up arbitrary rules. The term SECDED does not incorporate any guarantees about which part of a system it applies to. It's just a mathematical statement about the strength of the ECC in use plus the implication that detectable but uncorrectable errors are reported.

What you're looking for requires more words to fully specify, probably including the term "end to end".

[ Parent | on HN ]
Re:Micron Introduces 128 GB DDR5-8000 RDIMMs with Monolithic... by jeffbee on Monday November 13, 2023 @02:28PM (#38254166)
Your mantra is sort of hilarious because with current technology SECDEC is the worst ECC you can buy. If that's what you are getting on a DDR5 server today, the most likely reason is your integrator has made a mistake.
[ Parent | on HN ]