ASM:Topology

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Contents 1 ACPI Extended Topology 1.1 Building the Program 1.1.1 Prerequesites 1.1.2 Getting the Source Files 1.1.3 Build the Program 1.2 Running x2topology

ACPI Extended Topology

Building the Program

Prerequesites

• The Linux Operating System.
• Any Linux package which provides the taskset command that allows the Processor affinity ; util-linux if running ArchLinux.
• The GNU gcc C compiler.

Getting the Source Files

In the repository, download the following files in a project directory, such as x2topology

• x2topology.c
• x2topology.sh
• Optionally, the binary executable file : x2topology

Build the Program

• Compile the C source file

gcc x2topology.c -o x2topology

• Give the executable permission to the downloaded Bash script

chmod +x x2topology.sh

Running x2topology

• Remark: You may add your project directory to the executable PATH, or invoke x2topology with a ./ prefix (meaning in the current directory)

1. Launch the script x2topology.sh which iterates through all the enabled Cores

./x2topology.sh

• Using a Core i7, Nehalem architecture, Hyper-threading and 4 Cores enabled, it outputs:

OS APIC Thread Core 0x1 0 0 0 0x2 2 0 1 0x4 4 0 2 0x8 6 0 3 0x10 1 1 0 0x20 3 1 1 0x40 5 1 2 0x80 7 1 3

• Using a Core i7, Nehalem architecture, Hyper-threading disabled and 4 Cores enabled, it outputs:

OS APIC Thread Core 0x1 0 0 0 0x2 2 0 1 0x4 4 0 2 0x8 6 0 3 0x10 0x20 0x40 0x80

• Using a Core i7, Nehalem architecture, Hyper-threading disabled and only 1 Core enabled (3 Cores disabled), it outputs:

OS APIC Thread Core 0x1 0 0 0 0x2 0x4 0x8 0x10 0x20 0x40 0x80

1. x2topology, binary and shell script, can be lauched with a verbose option to get details:

./x2topology -v ./x2topology.sh -v