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# system.asynchronous_metrics {#system_tables-asynchronous_metrics}
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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.
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- [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.
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- [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` .
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[Original article ](https://clickhouse.tech/docs/en/operations/system-tables/asynchronous_metrics ) <!--hide-->