site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com On Feb 16, 2006, at 2:50 PM, Brian Bechtel wrote: Now, I would be willing to blame this on bad memory, but the machine runs weeks on end performing other heavy computational tasks (although in 32-bit mode). The same problem also occurs on a separate dual G5 with 8 GB of memory. panic(cpu 2 caller 0x000A8D80): Uncorrectable machine check: pc = FFFFFFFFFFFF8260, msr = 900000000004F030, dsisr = 00200000, dar = 00000000B0011C00 Your RAM is incompatible with your machine, or you have a bad RAM DIMM. Run the Apple Hardware Test which came with the machine. In 32-bit mode, your application can only access 4GB of RAM. In 64-bit mode, it's accessing previously unused RAM; accessing that RAM is causing the machine check panic. _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... On 2/15/06, Tor Andre Myrvoll <myrvoll@iet.ntnu.no> wrote: The problem is that if I let the program use 6-7 GB out of my total of 8 GB, the machine will eventually crash (see an example of a crash- dump below. The cpu causing the panic varies from time to time). Note that the machine is not swapping when these crashes occur. It's not necessarily that simple. The presence of a VM system and buffer cache in the OS which both understand 64-bit physical addresses means there is no such thing as RAM which is only available to a 64-bit process. Especially on Tiger, even if he never ran anything but 32-bit processes, the system could easily use all available physical memory. This email sent to site_archiver@lists.apple.com