ClickHouse/docs/en/operations/system-tables/asynchronous_metric_log.md
Bharat Nallan Chakravarthy 1d788ac1c1 fix docs
2023-11-27 08:05:14 -08:00

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---
slug: /en/operations/system-tables/asynchronous_metric_log
---
# asynchronous_metric_log
Contains the historical values for `system.asynchronous_metrics`, which are saved once per minute. Enabled by default.
Columns:
- `hostname` ([LowCardinality(String)](../../sql-reference/data-types/string.md)) — Hostname of the server executing the query.
- `event_date` ([Date](../../sql-reference/data-types/date.md)) — Event date.
- `event_time` ([DateTime](../../sql-reference/data-types/datetime.md)) — Event time.
- `name` ([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_metric_log LIMIT 3 \G
```
``` text
Row 1:
──────
hostname: clickhouse.eu-central1.internal
event_date: 2023-11-14
event_time: 2023-11-14 14:39:07
metric: AsynchronousHeavyMetricsCalculationTimeSpent
value: 0.001
Row 2:
──────
hostname: clickhouse.eu-central1.internal
event_date: 2023-11-14
event_time: 2023-11-14 14:39:08
metric: AsynchronousHeavyMetricsCalculationTimeSpent
value: 0
Row 3:
──────
hostname: clickhouse.eu-central1.internal
event_date: 2023-11-14
event_time: 2023-11-14 14:39:09
metric: AsynchronousHeavyMetricsCalculationTimeSpent
value: 0
```
**See Also**
- [system.asynchronous_metrics](../system-tables/asynchronous_metrics.md) — Contains metrics, calculated periodically in the background.
- [system.metric_log](../system-tables/metric_log.md) — Contains history of metrics values from tables `system.metrics` and `system.events`, periodically flushed to disk.