ClickHouse/docs/en/operations/system-tables/asynchronous_metrics.md
2022-06-02 04:55:18 -06:00

39 lines
2.0 KiB
Markdown

# asynchronous_metrics
Contains metrics that are calculated periodically in the background. For example, the amount of RAM in use.
Columns:
- `metric` ([String](../../sql-reference/data-types/string.md)) — Metric name.
- `value` ([Float64](../../sql-reference/data-types/float.md)) — Metric value.
**Example**
``` sql
SELECT * FROM system.asynchronous_metrics LIMIT 10
```
``` text
┌─metric──────────────────────────────────┬──────value─┐
│ jemalloc.background_thread.run_interval │ 0 │
│ jemalloc.background_thread.num_runs │ 0 │
│ jemalloc.background_thread.num_threads │ 0 │
│ jemalloc.retained │ 422551552 │
│ jemalloc.mapped │ 1682989056 │
│ jemalloc.resident │ 1656446976 │
│ jemalloc.metadata_thp │ 0 │
│ jemalloc.metadata │ 10226856 │
│ UncompressedCacheCells │ 0 │
│ MarkCacheFiles │ 0 │
└─────────────────────────────────────────┴────────────┘
```
**See Also**
- [Monitoring](../../operations/monitoring.md) — Base concepts of ClickHouse monitoring.
- [system.metrics](../../operations/system-tables/metrics.md#system_tables-metrics) — Contains instantly calculated metrics.
- [system.events](../../operations/system-tables/events.md#system_tables-events) — Contains a number of events that have occurred.
- [system.metric_log](../../operations/system-tables/metric_log.md#system_tables-metric_log) — Contains a history of metrics values from tables `system.metrics` and `system.events`.
[Original article](https://clickhouse.com/docs/en/operations/system-tables/asynchronous_metrics) <!--hide-->