Re: 2.4.25 kerne hukommelsedetektering

[Claus Hindsgaul <claus_h@image.dk>]

tor, 2004-04-08 kl. 15:30 skrev Lars E. D. Jensen:
> Hej
> 
> Min server har 2 GB ram installeret, men Debian "opdager" kun 1 GB ram.
> Bios fortæller, at der er 2 GB ram installeret.
> 
> Hvad kan årsagen være til dette?

Tjek din indstilling af CONFIG_NOHIGHMEM i din kerne. Du finder den
under "Processor type and features":

  │ Linux can use up to 64 Gigabytes of physical memory on x86 systems.     │
  │ However, the address space of 32-bit x86 processors is only 4           │
  │ Gigabytes large. That means that, if you have a large amount of         │
  │ physical memory, not all of it can be "permanently mapped" by the       │
  │ kernel. The physical memory that's not permanently mapped is called     │
  │ "high memory".                                                          │
  │                                                                         │
  │ If you are compiling a kernel which will never run on a machine with    │
  │ more than 960 megabytes of total physical RAM, answer "off" here (defau │
  │ choice and suitable for most users). This will result in a "3GB/1GB"    │
  │ split: 3GB are mapped so that each process sees a 3GB virtual memory    │
  │ space and the remaining part of the 4GB virtual memory space is used    │
  │ by the kernel to permanently map as much physical memory as             │
  │ possible.
  │ If more than 4 Gigabytes is used then answer "64GB" here. This          │
  │ selection turns Intel PAE (Physical Address Extension) mode on.         │
  │ PAE implements 3-level paging on IA32 processors. PAE is fully          │
  │ supported by Linux, PAE mode is implemented on all recent Intel         │
  │ processors (Pentium Pro and better). NOTE: If you say "64GB" here,      │
  │ then the kernel will not boot on CPUs that don't support PAE!           │
  │                                                                         │
  │ The actual amount of total physical memory will either be auto          │
  │ detected or can be forced by using a kernel command line option such    │
  │ as "mem=256M". (Try "man bootparam" or see the documentation of your    │
  │ boot loader (grub, lilo or loadlin) about how to pass options to the    │
  │ kernel at boot time.)                                                   │
  │                                                                         │
  │ If unsure, say "off".


-- 
Claus Hindsgaul <claus_h@image.dk>