Re: 32bits and 3G memory limit

[Stan Hoeppner <stan@hardwarefreak.com>]

Aaron Toponce put forth on 6/21/2010 10:09 AM:

> A 32-bit system, is a system that can address at most 2^32 bits of
> memory for any given process. Most 32-bit kernels these days, however,
> can address much more thanks to the physical address extensions (PAE),
> typically 64 GB. But that still means that each process can only address
> 2^32, or 4GB of RAM.

This 4GB process space limit is a user space process limit.

There is no limit on the kernel itself.  A PAE enabled kernel can directly use
all 64GB of RAM for its own needs, i.e. for page/buffer cache, ramdisk, etc.

-- 
Stan