Messages in this thread | | | Date | Tue, 19 Nov 1996 20:58:55 -0500 (EST) | From | "Richard B. Johnson" <> | Subject | Re: Memory Trauam |
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On Tue, 19 Nov 1996, Greg Alexander wrote:
> > You write something out, you read it back in, it's still in the > cache, so you're not actually ever reading from the SIMM again. There is > an instruction to clear the cache, but I don't know if it would be > implemented on all platforms because I really don't see the point in > having such an instruction. :)
Well sometimes. Many caches are write-through, which solves a lot of problems. Some Cyrix chips can have write-behind enabled, but due to other hardware "bugs" (reserved word, normally used for software), many such systems fail when running multitasking operating systems.
One thing is certainly true. Power-on-self-test and check-memory routines are just for "show". You could lean a lot more by seeing if the system boots and can then do something useful for several days.
I designed the operating system for a CAT-Scanner. The "Program managers" insisted that, before anything useful is accomplished, a complete suite of test routines be run. I have never, ever, seen these routines report any errors. However, I have seen many systems fail because of errors that the test routines were designed to find!
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