RHCE: Red Hat Certified Engineer Study Guide - Directory UMM

24 Chapter 2 � Hardware Basics
Memory
CPUs and Buses
TABLE 2.1 Supported CPUs
SMP doesn’t increase the execution speed of processes; it merely lets multiple
processes run concurrently. Single-threaded applications, which run on a single
processor, do not benefit from SMP.
The Linux 2.2 kernel that ships with Red Hat Linux 6.2 generally auto-detects the
amount of installed RAM (random access memory). However, the standard kernel
cannot auto-detect or use more than 1GB of RAM. To enable support for
more than 1GB of RAM, you must modify the include/asm-i386/page.h
header file and recompile the kernel. You may also need to pass a mem parameter
to lilo, instructing lilo to ignore the physical memory size reported by a system
BIOS that is unable to detect and report more than 64MB of RAM.
When running on Intel-architecture CPUs, Red Hat Linux permits a system
to access only 4GB of virtual memory, including both physical memory and
swap memory. For example, a system that can access 2GB of physical memory
can access only 2GB of swap memory.
Red Hat Linux supports the Intel CPU family and Intel-compatibles, including
those made by AMD, Cyrix, and Winchip. Table 2.1 summarizes the CPUs
that are supported by Red Hat Linux.
Support Level CPU
Tier 1 Intel Celeron
Intel Pentium
Intel Pentium II
Intel Pentium III
Intel Pentium SMP
AMD K6-2
AMD K6-3