title: GAP Benchmark Suite (GAPBS) tests tags: - x86 - fullsystem permalink: resources/gapbs shortdoc: > This resource implementes the GAP benchmark suite. author: [“Marjan Fariborz”] license: BSD-3-Clause

This document provides instructions to create a GAP Benchmark Suite (GAPBS) disk image, which, along with an example script, may be used to run GAPBS within gem5 simulations. The example script uses a pre-built disk-image.

A pre-built disk image, for X86, can be found, gzipped, here: http://dist.gem5.org/dist/v22-0/images/x86/ubuntu-18-04/gapbs.img.gz.

Building the Disk Image

Assuming that you are in the src/gapbs/ directory, first create m5 (which is needed to create the disk image):

git clone https://gem5.googlesource.com/public/gem5
cd gem5/util/m5
scons build/x86/out/m5

To create the disk image you need to add the packer binary in the disk-image directory:

cd disk-image/
./build.sh          # the script downloading packer binary and building the disk image

After this process succeeds, the disk image can be found on the src/gapbs/disk-image/gapbs-image/gapbs.

GAPBS disk image can support both real and synthetic graph inputs. The current pre-built disk image contains only one graph input which includes the New York city road map (with 733K nodes) it can be found: http://users.diag.uniroma1.it/challenge9/download.shtml.

To use other graphs simply copy the graph in the gapbs/ directory and add them to gapbs/gapbs.json.

Simulating GAPBS using an example script

An example script with a pre-configured system is available in the following directory within the gem5 repository:

gem5/configs/example/gem5_library/x86-gapbs-benchmarks.py

The example script specifies a system with the following parameters:

• A SimpleSwitchableProcessor (KVM for startup and TIMING for ROI execution). There are 2 CPU cores, each clocked at 3 GHz.
• 2 Level MESI_Two_Level cache with 32 kB L1I and L1D size, and, 256 kB L2 size. The L1 cache(s) has associativity of 8, and, the L2 cache has associativity 16. There are 2 L2 cache banks.
• The system has 3 GB SingleChannelDDR4_2400 memory.
• The script uses x86-linux-kernel-4.19.83 and x86-gapbs, the disk image created from following the instructions in this README.md.

The example script must be run with the X86 binary. To build:

git clone https://gem5.googlesource.com/public/gem5
cd gem5
scons build/X86/gem5.opt -j<proc>

Once compiled, you may use the example config file to run the GAPBS benchmark programs using the following command:

# In the gem5 directory
build/X86/gem5.opt \
configs/example/gem5_library/x86-gapbs-benchmarks.py \
--benchmark <benchmark_program> \
--synthetic <synthetic> \
--size <size_or_graph_name>

Description of the three arguments, provided in the above command are:

• --benchmark, which refers to one of 5 benchmark programs, provided in the GAP Benchmark Suite. These include cc, bc, tc, pr and bfs. For more information on the workloads can be found at http://gap.cs.berkeley.edu/benchmark.html.
• --synthetic refers whether to use a synthetic or a real graph. It accepts a boolean value.
• --size, which refers to either the size of a synthetic graph from 1 to 16 nodes, or, a real graph. The real graph included in the pre-built disk-image is USA-road-d.NY.gr. Note that --synthetic True and --size USA-road-d.NY.gr cannot be combined, and, vice versa for real graphs.