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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 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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> 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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> |
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You know those multi terabyte hard drives they make, every bit of those |
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platters that are actively in use must work perfectly. If just one |
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thing, just one tiny bit, is not working correctly, you get bad data. |
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With computers, one bit of bad data means something doesn't work be it |
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hard drives or memory or even the CPU. You may can live with it on |
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widoze but not Linux. Linus maximizes the use of memory more so than |
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windoze. I have 16Gbs of ram here. Even if I don't compile anything, |
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eventually all my memory will be used by cache if nothing else. Once |
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that cache hits a bad spot, there is trouble. |
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Might I also add, whoever told you to live with it, I hope they don't |
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work on airplanes and I wouldn't take advice from them to much on puter |
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stuff in the future. |
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Just my $0.02 worth. |
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|
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Dale |
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|
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:-) :-) |