mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-26 17:41:59 +00:00
8f03e526a4
* Edit and translate Отредактировал английскую версию текстов документов и перевел изменения на русский язык. * Update trace_log.md Исправляю битые ссылки. * Fixing broken links Исправил битые ссылки. * Fixing broken links Поправил битую ссылку, добавив раздел в русскую версию. Co-authored-by: Dmitriy <sevirov@yandex-team.ru>
55 lines
2.9 KiB
Markdown
55 lines
2.9 KiB
Markdown
# system.trace_log {#system_tables-trace_log}
|
|
|
|
Contains stack traces collected by the sampling query profiler.
|
|
|
|
ClickHouse creates this table when the [trace_log](../../operations/server-configuration-parameters/settings.md#server_configuration_parameters-trace_log) server configuration section is set. Also the [query_profiler_real_time_period_ns](../../operations/settings/settings.md#query_profiler_real_time_period_ns) and [query_profiler_cpu_time_period_ns](../../operations/settings/settings.md#query_profiler_cpu_time_period_ns) settings should be set.
|
|
|
|
To analyze logs, use the `addressToLine`, `addressToSymbol` and `demangle` introspection functions.
|
|
|
|
Columns:
|
|
|
|
- `event_date` ([Date](../../sql-reference/data-types/date.md)) — Date of sampling moment.
|
|
|
|
- `event_time` ([DateTime](../../sql-reference/data-types/datetime.md)) — Timestamp of the sampling moment.
|
|
|
|
- `event_time_microseconds` ([DateTime](../../sql-reference/data-types/datetime.md)) — Timestamp of the sampling moment with microseconds precision.
|
|
|
|
- `timestamp_ns` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Timestamp of the sampling moment in nanoseconds.
|
|
|
|
- `revision` ([UInt32](../../sql-reference/data-types/int-uint.md)) — ClickHouse server build revision.
|
|
|
|
When connecting to the server by `clickhouse-client`, you see the string similar to `Connected to ClickHouse server version 19.18.1 revision 54429.`. This field contains the `revision`, but not the `version` of a server.
|
|
|
|
- `timer_type` ([Enum8](../../sql-reference/data-types/enum.md)) — Timer type:
|
|
|
|
- `Real` represents wall-clock time.
|
|
- `CPU` represents CPU time.
|
|
|
|
- `thread_number` ([UInt32](../../sql-reference/data-types/int-uint.md)) — Thread identifier.
|
|
|
|
- `query_id` ([String](../../sql-reference/data-types/string.md)) — Query identifier that can be used to get details about a query that was running from the [query_log](#system_tables-query_log) system table.
|
|
|
|
- `trace` ([Array(UInt64)](../../sql-reference/data-types/array.md)) — Stack trace at the moment of sampling. Each element is a virtual memory address inside ClickHouse server process.
|
|
|
|
**Example**
|
|
|
|
``` sql
|
|
SELECT * FROM system.trace_log LIMIT 1 \G
|
|
```
|
|
|
|
``` text
|
|
Row 1:
|
|
──────
|
|
event_date: 2020-09-10
|
|
event_time: 2020-09-10 11:23:09
|
|
event_time_microseconds: 2020-09-10 11:23:09.872924
|
|
timestamp_ns: 1599762189872924510
|
|
revision: 54440
|
|
trace_type: Memory
|
|
thread_id: 564963
|
|
query_id:
|
|
trace: [371912858,371912789,371798468,371799717,371801313,371790250,624462773,566365041,566440261,566445834,566460071,566459914,566459842,566459580,566459469,566459389,566459341,566455774,371993941,371988245,372158848,372187428,372187309,372187093,372185478,140222123165193,140222122205443]
|
|
size: 5244400
|
|
```
|
|
|
|
[Original article](https://clickhouse.tech/docs/en/operations/system_tables/trace_log) <!--hide--> |