OpenSearch Benchmark stores metrics in the `benchmark-metrics-*` indexes. A new index is created each month. The following is an example metric record stored in the `benchmark-metrics-2023-08` index:
The timestamp of when the sample was taken since the epoch, in milliseconds. For request-related metrics, such as `latency` or `service_time`, this is the timestamp of when OpenSearch Benchmark issued the request.
The relative time since the start of the benchmark, in milliseconds. This is useful for comparing time-series graphs across multiple tests. For example, you can compare the indexing throughput over time across multiple tests.
The `environment` describes the origin of a metric record. This is defined when initially [configuring]({{site.url}}{{site.baseurl}}/benchmark/configuring-benchmark/) OpenSearch Benchmark. You can use separate environments for different benchmarks but store the metric records in the same index.
The actual metric name and value, with an optional unit. Depending on the nature of a metric, it is either sampled periodically by OpenSearch Benchmark, for example, CPU utilization or query latency, or measured once, for example, the final size of the index.
Determines whether to configure a benchmark to run in warmup mode by setting it to `warmup` or `normal`. Only `normal` samples are considered for the results that are reported.
The meta information for each metric record, including the following:
- CPU info: The number of physical and logical cores and the model name.
- OS info: The name and version of the operating system.
- Hostname.
- Node name: A unique name given to each node when OpenSearch Benchmark provisions the cluster.
- Source revision: The Git hash of the version of OpenSearch that is benchmarked.
- Distribution version: The distribution version of OpenSearch that is benchmarked.
- Custom tags: You can define custom tags by using the command line flag `--user-tags`. The tags are prefixed by `tag_` in order to avoid accidental clashes with OpenSearch Benchmark internal tags.
- Operation specific: An optional substructure of the operation. For bulk requests, this may be the number of documents; for searches, the number of hits.
Depending on the metric record, some meta information might be missing.
## Next steps
- For more information about how to access OpenSearch Benchmark metrics, see [Metrics]({{site.url}}{{site.baseurl}}/benchmark/metrics/index/).
- For more information about the metrics stored in OpenSearch Benchmark, see [Metric keys]({{site.url}}{{site.baseurl}}/benchmark/metrics/metric-keys/).