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ZombiePhysicist

macrumors 68030
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May 22, 2014
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From my understanding, with modern systems you could easily encounter one parity error a day.

So, is there a way to detect/see what ECC/parity bit-flip errors occurred and were corrected on our Mac Pros?

I would love it if there was an app, like in istat menus, or something that would keep stats of when I encounter a bit-flip error and when the Mac Pro corrects it. Is there some log or some app that does this?

Thanks for any pointers!
 
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mikas

macrumors 6502a
Sep 14, 2017
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They should be reported in system report at hardware/memory if there are any. I believe I saw errors on "about this Mac" memory tab too on my 2013 when I had some bad memory, with
kisspng-warning-sign-computer-icons-clip-art-warning-icon-5b31bd67368be5.4827407215299864072234.jpg
icon besides the ram module with error.
 
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ZombiePhysicist

macrumors 68030
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May 22, 2014
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If they are reported, where in the system?

Sorry, to be more clear, i do not mean bad memory modules. I mean well working memory modules that detect a bit was flipped improperly and correct the error with parity so the system can keep on working.
 

mikas

macrumors 6502a
Sep 14, 2017
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Finland
Like this.
1659813396242.png

But only if there are errors, otherwise no indications.
And also in System Information panels it's reported if any occur, about like this.
1659813570300.png

I don't think ecc errors are, or should be, that common. I changed the memory modules on mine, because I was getting thousands of errors per session. No crash because they seemed to be correctable errors, all of them, so the modules worked like they should. Detected and corrected the errors. But I couldn't stand the situation, and updated all dimms to new ones. Errors dissapeared almost totally. One or two times I saw a couple errors after dimm upgrade.
 
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ZombiePhysicist

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May 22, 2014
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Yea yours seems like it was a bad chip, but maybe you’re on to how where the errors are coming from.

My guess is if it’s reported as you show you’re getting like you say thousands of errors per day. I guess the question is, where is the system profiler getting such reports from. There must be some log somewhere and if it shows like one error a week, the system profiler might ignore it but if it gets thousands of errors a day, it will report it in the system profiler?

Ecc errors are pretty common these days. It seems like you could expect an error per day. It seems ther should be some way to know when they happen and get reports.

 
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mikas

macrumors 6502a
Sep 14, 2017
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Finland
It's been a couple of years or so from that incident of my memory. And I'm not the right person to know about those inner workings for sure. But, I'd guess it must come from the memory controller. Dimms do have a special circuitry to detect and correct the errors, so there's no other way than that they report the memory controller, and the controller passes the report up.

Again I don't know, but the reasons and spesifics of the errors probably are not something to be known in detail for a user, even not a system admin or support.

I have believed it's more of a physical thing to happen in modules, and not a logical thing or error. I have read some wikis about all that, but did not dive into it more than I needed to.

About the increased commonness of ecc errors; well, maybe so, but if a PC without ECC can manage hundreds of days uptime, there can't be that much of memory errors, I think. I have used a lot of Macs with uptimes of hundreds of days. I there were lots of memory errors, it would either give false information, or panic, eventually.

But yeah. I wouldn't know for sure though.
 
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m1maverick

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Nov 22, 2020
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I don't know about macOS but on one of my Solaris systems running on the SPARC architecture I noticed an ECC correction error when the system was started. It was recorded in /var/log/messages.

You may want to check /var/log/system.log on macOS (at least High Sierra).
 
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deconstruct60

macrumors G5
Mar 10, 2009
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From my understanding, with modern systems you could easily encounter one parity error a day.

So, is there a way to detect/see what ECC/parity bit-flip errors occurred and were corrected on our Mac Pros?


most everything in the GUI system profiler you can get to with the command line tool .



FreeBSD drops them in /var/log/messages


The console app allows you to pattern match on log entries . So something like. “Member error” could get you timestamps , but cryptic descriptions of where .
( Linux has rasdeamon . FreeBSD is still leveraging mcelog )


I would love it if there was an app, like in istat menus,

not sure if EtreCheck tracks this issue or not .
 
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ZombiePhysicist

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May 22, 2014
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I went into console.app and did some searches. Nothing pops up, but it's possible I have no errors. Also possible I don't know what I'm searching for. Searched for memory, and ECC.

Ran EtreCheck (interesting app, thanks), but nothing I could see dealing with ECC.
 
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