Hi Derek,

> I have leaf Bering uclib running on a box with 2Gb memory but it only
> show 1Gb in /proc/meminfo
>
> Is possibly a limit in Leaf or have is it likely I have a hardware
> problem?
>
It's because the kernel is compiled with "CONFIG_NOHIGHMEM=y" in the
kernel config. Bering-uClibc is an embedded distro, using 2G of memory is
really overkill.

>From the kernel documentation:

"CONFIG_NOHIGHMEM
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 (default
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 the machine has between 1 and 4 Gigabytes physical RAM, then answer
"4GB" here.

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".
"

Eric

>
> TIA
>
>
> Derek
>
>
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Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642
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