mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-01 03:52:15 +00:00
40 lines
5.0 KiB
Markdown
40 lines
5.0 KiB
Markdown
# system.metrics {#system_tables-metrics}
|
|
|
|
此系统表包含可以即时计算或具有当前值的指标。例如，同时处理的查询数量或当前的复制延迟。这个表始终是最新的。
|
|
|
|
列:
|
|
|
|
- `metric` ([字符串](../../sql-reference/data-types/string.md)) — 指标名称.
|
|
- `value` ([Int64](../../sql-reference/data-types/int-uint.md)) — 指标的值.
|
|
- `description` ([字符串](../../sql-reference/data-types/string.md)) — 指标的描述.
|
|
|
|
对于支持的指标列表，您可以查看 [src/Common/CurrentMetrics.cpp](https://github.com/ClickHouse/ClickHouse/blob/master/src/Common/CurrentMetrics.cpp) ClickHouse 的源文件。
|
|
|
|
**示例**
|
|
|
|
``` sql
|
|
SELECT * FROM system.metrics LIMIT 10
|
|
```
|
|
|
|
``` text
|
|
┌─metric─────────────────────┬─value─┬─description──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
|
|
│ Query │ 1 │ Number of executing queries │
|
|
│ Merge │ 0 │ Number of executing background merges │
|
|
│ PartMutation │ 0 │ Number of mutations (ALTER DELETE/UPDATE) │
|
|
│ ReplicatedFetch │ 0 │ Number of data parts being fetched from replicas │
|
|
│ ReplicatedSend │ 0 │ Number of data parts being sent to replicas │
|
|
│ ReplicatedChecks │ 0 │ Number of data parts checking for consistency │
|
|
│ BackgroundPoolTask │ 0 │ Number of active tasks in BackgroundProcessingPool (merges, mutations, fetches, or replication queue bookkeeping) │
|
|
│ BackgroundSchedulePoolTask │ 0 │ Number of active tasks in BackgroundSchedulePool. This pool is used for periodic ReplicatedMergeTree tasks, like cleaning old data parts, altering data parts, replica re-initialization, etc. │
|
|
│ DiskSpaceReservedForMerge │ 0 │ Disk space reserved for currently running background merges. It is slightly more than the total size of currently merging parts. │
|
|
│ DistributedSend │ 0 │ Number of connections to remote servers sending data that was INSERTed into Distributed tables. Both synchronous and asynchronous mode. │
|
|
└────────────────────────────┴───────┴──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
|
|
```
|
|
|
|
**另请参阅**
|
|
|
|
- [system.asynchronous_metrics](../../operations/system-tables/asynchronous_metrics.md#system_tables-asynchronous_metrics) — 包含周期性的计算指标。
|
|
- [system.events](../../operations/system-tables/events.md#system_tables-events) — 包含发生的一些事件。
|
|
- [system.metric_log](../../operations/system-tables/metric_log.md#system_tables-metric_log) — 包含`system.metrics`表和`system.events`表的历史指标值。
|
|
- [监控](../../operations/monitoring.md) — ClickHouse 监控的基本概念。
|