Query Management

Warning! This page documents an old version of InfluxDB, which is no longer actively developed. InfluxDB v1.4 is the most recent stable version of InfluxDB.

With InfluxDB’s query management features, users are able to identify currently-running queries, kill queries that are overloading their system, and prevent and halt the execution of inefficient queries with several configuration settings.

SHOW QUERIES KILL QUERY Configuration Settings

List currently-running queries with SHOW QUERIES

SHOW QUERIES lists the query ID, query text, relevant database, and duration of all currently-running queries on your InfluxDB instance. For InfluxEnterprise clusters, the SHOW QUERIES output also includes the TCP host.

Syntax:

SHOW QUERIES

Example:

> SHOW QUERIES
qid query                               database duration status
--- -----                               -------- -------- ------
37  SHOW QUERIES                                 100368u  running
36  SELECT mean(myfield) FROM mymeas    mydb     3s       running
Explanation of the output:
  • qid: The ID number of the query.
  • query: The query text.
  • database: The database targeted by the query.
  • duration: The length of time that the query has been running.
  • status: Current status of the query when SHOW QUERIES was executed.

See Query Language Reference for an explanation of InfluxDB’s time units.

Stop currently-running queries with KILL QUERY

KILL QUERY tells InfluxDB to stop running the relevant query.

Syntax:

Where qid is the query ID, displayed in the SHOW QUERIES output:

KILL QUERY <qid>

InfluxEnterprise clusters: To kill queries on a cluster, you need to specify the query ID (qid) and the TCP host (for example, myhost:8088), available in the SHOW QUERIES output.

>KILL QUERY <qid> ON "<host>"
>```

A successful `KILL QUERY` query returns no results.

#### Examples:

– kill query with qid of 36 on the local host KILL QUERY 36

– kill query on InfluxEnterprise cluster KILL QUERY 53 ON “myhost:8088”


## Configuration settings for query management

The following configuration settings are in the
[[coordinator]](/influxdb/v1.3/administration/config/#coordinator) section of the
configuration file.

### max-concurrent-queries

The maximum number of running queries allowed on your instance.
The default setting (`0`) allows for an unlimited number of queries.

If you exceed `max-concurrent-queries`, InfluxDB does not execute the query and
outputs the following error:

ERR: max concurrent queries reached


### query-timeout

The maximum time for which a query can run on your instance before InfluxDB
kills the query.
The default setting (`"0"`) allows queries to run with no time restrictions.
This setting is a [duration literal](/influxdb/v1.3/query_language/spec/#durations).

If your query exceeds the query timeout, InfluxDB kills the query and outputs
the following error:

ERR: query timeout reached


### log-queries-after

The maximum time a query can run after which InfluxDB logs the query with a
`Detected slow query` message.
The default setting (`"0"`) will never tell InfluxDB to log the query.
This setting is a [duration literal](/influxdb/v1.3/query_language/spec/#durations).

Example log output with `log-queries-after` set to `"1s"`:

[query] 2016/04/28 14:11:31 Detected slow query: SELECT mean(usage_idle) FROM cpu WHERE time >= 0 GROUP BY time(20s) (qid: 3, database: telegraf, threshold: 1s)


`qid` is the id number of the query.
Use this value with [`KILL QUERY`](/influxdb/v1.3/troubleshooting/query_management/#stop-currently-running-queries-with-kill-query).

The default location for the log output file is `/var/log/influxdb/influxdb.log`. However on systems that use systemd (most modern Linux distributions) those logs are output to `journalctl`. You should be able to view the InfluxDB logs using the following command: `journalctl -u influxdb`


### max-select-point

The maximum number of [points](/influxdb/v1.3/concepts/glossary/#point) that a
`SELECT` statement can process.
The default setting (`0`) allows the `SELECT` statement to process an unlimited
number of points.

If your query exceeds `max-select-point`, InfluxDB kills the query and outputs
the following error:

ERR: max number of points reached


### max-select-series

The maximum number of [series](/influxdb/v1.3/concepts/glossary/#series) that a
`SELECT` statement can process.
The default setting (`0`) allows the `SELECT` statement to process an unlimited
number of series.

If your query exceeds `max-select-series`, InfluxDB does not execute the query
and outputs the following error:

ERR: max select series count exceeded: series


### max-select-buckets

The maximum number of `GROUP BY time()` buckets that a query can process.
The default setting (`0`) allows a query to process an unlimited number of
buckets.

If your query exceeds `max-select-buckets`, InfluxDB does not execute the query
and outputs the following error:

ERR: max select bucket count exceeded: buckets ```