On Fri, 2013-01-18 at 08:04 -0700, Warren Block wrote: > On Fri, 18 Jan 2013, Ronald Klop wrote: > > > Memory chips gone bad? Power (or other) cables gone loose? > > Memory failures will cause intermittent and mysterious things. Easy to > test, too, just run memtest86 on it for a while. Do that before > rebuilding. If memory is failing, corrupted data could be written to > disk. > > I had a Crucial DIMM fail spontaneously a couple of weeks ago. Working > one minute, totally failed the next. The machine rebooted, for no > visible reason. After it came back up, compiles failed, always with > different errors and in different places. > > Power supplies also fail, as do motherboards. These are both harder to > swap out than memory, so test the memory first.
I tend to agree, a machine that starts rebooting spontaneously when nothing significant changed and it used to be stable is usually a sign of a failing power supply or memory. But I disagree about memtest86. It's probably not completely without value, but to me its value is only negative: if it tells you memory is bad, it is. If it tells you it's good, you know nothing. Over the years I've had 5 dimms fail. memtest86 found the error in one of them, but said all the others were fine in continuous 48-hour tests. I even tried running the tests on multiple systems. The thing that always reliably finds bad memory for me is /usr/ports/math/mprime run in test/benchmark mode. It often takes 24 or more hours of runtime, but it will find your bad memory. -- Ian _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"