benchmarks/

Benchmark tools

These scripts are tools for collecting performance data for Docker-based tests.

Setup

The scripts assume the following:

• You have a local machine with bazel installed.
• You have some machine(s) with docker installed. These machines will be refered to as the "Environment".
• Environment machines have the runtime(s) under test installed, such that you can run docker with a command like: docker run --runtime=$RUNTIME your/image.
• You are able to login to machines in the environment with the local machine via ssh and the user for ssh can run docker commands without using sudo.
• The docker daemon on each of your environment machines is listening on unix:///var/run/docker.sock (docker's default).

For configuring the environment manually, consult the dockerd documentation.

Environment

All benchmarks require a user defined yaml file describe the environment. These files are of the form:

machine1: local
machine2:
  hostname: 100.100.100.100
  username: username
  key_path: ~/private_keyfile
  key_password: passphrase
machine3:
  hostname: 100.100.100.101
  username: username
  key_path: ~/private_keyfile
  key_password: passphrase

The yaml file defines an environment with three machines named machine1, machine2 and machine3. machine1 is the local machine, machine2 and machine3 are remote machines. Both machine2 and machine3 should be reachable by ssh. For example, the command ssh -i ~/private_keyfile username@100.100.100.100 (using the passphrase passphrase) should connect to machine2.

The above is an example only. Machines should be uniform, since they are treated as such by the tests. Machines must also be accessible to each other via their default routes. Furthermore, some benchmarks will meaningless if running on the local machine, such as density.

For remote machines, hostname, key_path, and username are required and others are optional. In addition key files must be generated using the instrcutions below.

The above yaml file can be checked for correctness with the validate command in the top level perf.py script:

bazel run :benchmarks -- validate $PWD/examples/localhost.yaml

Running benchmarks

To list available benchmarks, use the list commmand:

bazel run :benchmarks -- list

...
Benchmark: sysbench.cpu
Metrics: events_per_second
    Run sysbench CPU test. Additional arguments can be provided for sysbench.

    :param max_prime: The maximum prime number to search.

To run benchmarks, use the run command. For example, to run the sysbench benchmark above:

bazel run :benchmarks -- run --env $PWD/examples/localhost.yaml sysbench.cpu

You can run parameterized benchmarks, for example to run with different runtimes:

bazel run :benchmarks -- run --env $PWD/examples/localhost.yaml --runtime=runc --runtime=runsc sysbench.cpu

Or with different parameters:

bazel run :benchmarks -- run --env $PWD/examples/localhost.yaml --max_prime=10 --max_prime=100 sysbench.cpu

Writing benchmarks

To write new benchmarks, you should familiarize yourself with the structure of the repository. There are three key components.

Harness

The harness makes use of the docker py SDK. It is advisable that you familiarize yourself with that API when making changes, specifically:

• clients
• containers
• images

In general, benchmarks need only interact with the Machine objects provided to the benchmark function, which are the machines defined in the environment. These objects allow the benchmark to define the relationships between different containers, and parse the output.

Workloads

The harness requires workloads to run. These are all available in the workloads directory.

In general, a workload consists of a Dockerfile to build it (while these are not hermetic, in general they should be as fixed and isolated as possible), some parses for output if required, parser tests and sample data. Provided the test is named after the workload package and contains a function named sample, this variable will be used to automatically mock workload output when the --mock flag is provided to the main tool.

Writing benchmarks

Benchmarks define the tests themselves. All benchmarks have the following function signature:

def my_func(output) -> float:
    return float(output)

@benchmark(metrics = my_func, machines = 1)
def my_benchmark(machine: machine.Machine, arg: str):
    return "3.4432"

Each benchmark takes a variable amount of position arguments as harness.Machine objects and some set of keyword arguments. It is recommended that you accept arbitrary keyword arguments and pass them through when constructing the container under test.

To write a new benchmark, open a module in the suites directory and use the above signature. You should add a descriptive doc string to describe what your benchmark is and any test centric arguments.

Generating SSH Keys

The scripts only support RSA Keys, and ssh library used in paramiko. Paramiko only supports RSA keys that look like the following (PEM format):

$ cat /path/to/ssh/key

-----BEGIN RSA PRIVATE KEY-----
...private key text...
-----END RSA PRIVATE KEY-----

To generate ssh keys in PEM format, use the -t rsa -m PEM -b 4096. option.