FreeBSD 6.x CVSUP today crashes with zero load ...

[Thomas Nyström]

M.Hirsch wrote:
> Any hardware showing ECC errors should be replaced asap..

No. ALL memory will sooner or later show single bit error.

Several years ago I was checking this during my work at Ericsson.
There was a discussion if ECC should be present in the GSM-base-stations
or not. I had a special test-software running in several units looking
for soft-errors. Soft errors are bits that are flipped spontaneously in
the memory. When the bit are rewritten it will work OK again, no
permanent damage to the memory and no need to replace the memory.

During my test period (I think it was 6-8 monthes) I saw four occasions
when this occured (total amount of memory 96 MB).

ECC is intended to fix this: It will correct a single bit fault and
allow the system to contiune uninterrupted.

Of course this event should be logged and if it occurs several times
at the same place then it is time to replace the memory.

Of course memory should be better these days but.... knock on wood....

/thn [20 years as HW-designer, FreeBSD since 3.0]

-- 
---------------------------------------------------------------
Svensk Aktuell Elektronik AB                     Thomas Nyström
Box 10                                    Phone: +46 8 35 92 85
S-191 21  Sollentuna                        Fax: +46 8 35 92 86
Sweden                                      Email: thn at saeab.se
---------------------------------------------------------------