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On Friday, August 21, 2015 11:00:16 AM Alan Grimes wrote: |
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> Grant Edwards wrote: |
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> > On 2015-08-21, Alan McKinnon <alan.mckinnon@×××××.com> wrote: |
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> > |
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> >> Earlier I saw segfaults in gcc, and another poster pointed it out. |
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> >> |
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> >> When gcc segfaults, it is always suspicious mostly because the compiler |
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> >> is an app where we know the devs take extraordinary measures to prevent |
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it. |
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> >> |
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> >> The most common cause is faulty hardware (most often memory) as gcc |
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> >> tends to use all of it in ways no other app does. The usual procedure |
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> >> at this point is to run memtest for an extended period - say 48 |
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> >> hours, or even 72 for an older slow machine. |
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> > That is definitely good advice. I've run into this situation several |
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> > times. A machine had bad RAM that didn't seem to cause any problems |
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> > under "normal" operation. But, when trying to compile something large |
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> > like gcc, I would see non-repeatable segfaults (it wouldn't always |
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> > segfault at the exact same point). In those cases, I could often run |
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> > memtest for several passes and not see an error. But, _eventually_ |
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> > ramtest would catch it. Run memtest for a few days. Really. |
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> |
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> Yeah, I know there's a single bit error out at the end of RAM that will |
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> appear on the third or fourth pass... |
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> |
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> I have already RMA'd half of the ram in this machine because it was |
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> giving a whole fist-full of errors across two sticks... I run the rusty |
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> old bus on the CPU ( SIX CORES!!!!) a bit harder than it was intended |
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> in order to keep up with the new junk. My previous machine had ECC. =( |
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> |
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> I was advised to just jack the voltage a little bit and live with it. I |
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> guess I'd better run more tests and see what the situation is.... |
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> |
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> It just doesn't seem reasonable to demand that every bit in a 32 |
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> gigabyte memory bank be absolutely perfect.... |
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LOL. It's perfectly reasonable. |
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If it's under warranty, return it. And get a different brand cause it sounds |
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like what you got is crap. |
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If it's not under warranty and after running the test for an extended period |
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as adviced you're sure that it's only a single bad bit at the highest end you |
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can boot with the mem= option. Also see memmap and memtest. |
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https://www.kernel.org/doc/Documentation/kernel-parameters.txt |
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-- |
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Fernando Rodriguez |
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