JSON report

vegaload run -out report.json writes a JSON summary of the run. vegaload compare, -baseline and vegaload diagnose read this file.

All times are whole numbers of nanoseconds. Names end in _ns. A rate such as error_rate is a fraction: 0.02 is 2%.

Some sections appear only when they apply. This page was checked against real 0.9.0 files.

Top level

Field	Meaning
executor	The load shape, such as fixed-vus.
started_at	When the run started, as a UTC timestamp.
elapsed_ns	How long the run took.
total	Number of iterations or calls counted.
failed	How many of them failed.
error_rate	failed divided by total.
latency	The latency summary. See below.
time_series	The run, cut into slices over time.
thresholds	Each threshold and its result. Present when you set thresholds.
thresholds_passed	true if every threshold passed.
baseline	The result of the baseline gate. Present with -baseline.
steps	Results for each named step(). Present when the scenario uses steps.
protocols	Results for each protocol the run used.
checks	Pass and fail counts for each check. Present when the scenario uses checks.

latency

The same fields appear in steps and protocols.

Field	Meaning
min_ns, mean_ns, max_ns	Fastest, average and slowest call.
p50_ns, p90_ns, p95_ns, p99_ns	Percentiles. p95_ns means 95% of calls were this fast or faster.

time_series[]

Field	Meaning
offset_ns	Where this slice starts, counted from the start of the run.
requests	Calls in this slice.
failed	Failed calls in this slice.
rps	Calls per second in this slice.
error_rate	Failure fraction in this slice.

thresholds[]

Field	Meaning
name	The threshold as you wrote it.
metric	The metric, such as p95.
operator	The comparison, such as <.
value	The limit, as text, such as 500ms.
observed	What the run measured, as text.
passed	true or false.
step	The step the threshold is limited to. Present only for a step threshold.
protocol	The protocol the threshold is limited to. Present only for a protocol threshold.

baseline

Field	Meaning
path	The baseline file you gave.
max_regression_percent	The slack you allowed.
passed	true if no metric regressed beyond the slack.
metrics[]	One entry for error_rate and one for latency.p95. Each has name, baseline, candidate, unit and regressed.
notes[]	A plain sentence about the result.

steps[]

Field	Meaning
name	The step name.
total	How many times the step ran.
failed	How many runs failed.
error_rate	The failure fraction.
latency	The latency summary.

protocols[]

Field	Meaning
name	The protocol, such as http.
total, failed, error_rate	Counts and failure fraction for this protocol.
latency	The latency summary.
bytes_sent, bytes_received	Bytes moved.
bytes_per_second	Throughput.
operations[]	One entry per kind of call, such as GET. Each has name, total, failed, error_rate, latency, bytes_sent and bytes_received.

checks[]

Field	Meaning
name	The check name.
passes	How many times it passed.
fails	How many times it failed.

Example

A short run with one step and one check, trimmed:

{
  "executor": "fixed-vus",
  "total": 224,
  "failed": 0,
  "error_rate": 0,
  "latency": { "p50_ns": 26642194, "p95_ns": 40212388 },
  "thresholds": [
    { "name": "p95 < 500ms", "metric": "p95", "operator": "<",
      "value": "500ms", "observed": "40.22ms", "passed": true }
  ],
  "thresholds_passed": true,
  "steps": [{ "name": "list", "total": 224, "failed": 0 }],
  "checks": [{ "name": "status is 200", "passes": 224, "fails": 0 }]
}

To compare two reports, see Compare two runs. To explain one, see Explain a run.