Awesome

benchdiff

Runs go benchmarks on HEAD and a base branch and reports the resulting benchstat output.

See an example result here.

To learn about the benchdiff command that this action runs, visit https://github.com/WillAbides/benchdiff.

Inputs

benchdiff_args

Arguments for the benchdiff command line. This action will run the command line benchdiff <benchdiff_args> after making some adjustments to the arguments (listed below).

If --base-ref isn't present in the arguments, then --base-ref <default branch> will be added.

--json is always added because the action requires json formatted output.

--benchstat-output=markdown is added when no other benchstat-output value is set because the reports look best with markdown formatting.

Consider this example:

--cpu=1,2 --warmup-count=1 --warmup-time=10ms --tolerance=50 --debug

--cpu=1,2 is important on actions because runners have only two cores available to them.

--warmup-count=1 and warmup-time=10ms cause benchdiff to do a quick warmup before starting the benchmarks. This is important on actions because the runners appear to have a small amount of cpu burst available. If you burn through that in the warmup, then it makes for a better cmoparison between the real runs.

--tolerance=50 means that a benchmark isn't considered degraded unless it's delta is greater than +50%. Action runners can have inconsistent performance within the same run. This helps mitigate a lot of false alarms.

--debug causes benchdiff to output raw results to stderr (among other debug data). I like having this on just to see progress in the logs.

See https://github.com/willabides/benchdiff for all available flags.

benchdiff_version

default: 0.5.6

Version of the benchdiff command to use.

When a new version of this action is released, the default value will be updated to the latest version of benchdiff that isn't a breaking change from the previous default.

report_status

default: true

Whether to report the status. Any value other than "true" is interpreted as false.

I call this "status" because that's a better known term. What is actually created is a check-run.

status_name

default: benchdiff

Name to use in reporting status. This is the name of the check-run that is created.

status_sha

Report status to this sha. Default is the head of your benchdiff run.

status_on_degraded

default: failure

Status to report for degraded results.

Options are "success", "failure" and "neutral"

github_token

default: ${{ github.token }}

Authentication token to use for reporting status.

If you use a non-default token it needs to be a token for a GitHub App installation with permission to create a check-run.

Outputs

benchstat_output

Stdout from the benchdiff command.

bench_command

Command used to run benchmarks. This is derived from the benchdiff_args input.

degraded_result

Whether any of the benchmarks degraded between base and head.

head_sha

The git revision benchstat used as head.

base_sha

The git revision benchstat used as base.