The SHOW SESSIONS
statement lists details about currently active sessions, including:
- The address of the client that opened the session
- The node connected to
- How long the connection has been open
- Which queries are active in the session
- Which query has been running longest in the session
These details let you monitor the overall state of client connections and identify those that may need further investigation or adjustment.
Required privileges
No privileges are required to execute this statement. However, note that non-admin
users see only their own currently active sessions, whereas the admin
users see all users' currently active sessions.
Synopsis
- To list the active sessions across all nodes of the cluster, use
SHOW SESSIONS
orSHOW CLUSTER SESSIONS
. - To list the active sessions just on the local node, use
SHOW LOCAL SESSIONS
.
Response
The following fields are returned for each session:
Field | Description |
---|---|
node_id |
The ID of the node connected to. |
session_id |
The ID of the connected session. |
user_name |
The username of the connected user. |
client_address |
The address and port of the connected client. |
application_name |
The application name specified by the client, if any. For sessions from the built-in SQL client, this will be cockroach . |
active_queries |
The SQL queries currently active in the session. |
last_active_query |
The most recently completed SQL query in the session. |
session_start |
The timestamp at which the session started. |
oldest_query_start |
The timestamp at which the oldest currently active SQL query in the session started. |
kv_txn |
The ID of the current key-value transaction for the session. |
Examples
List active sessions across the cluster
> SHOW CLUSTER SESSIONS;
+---------+----------------------------------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------|----------------------------------+----------------------------------+--------------------------------------+
| node_id | session_id | user_name | client_address | application_name | active_queries | last_active_query | session_start | oldest_query_start | kv_txn
+---------+----------------------------------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------+----------------------------------+----------------------------------+--------------------------------------|
| 2 | 1530fd8813ad694b0000000000000001 | mroach | 192.168.0.72:56194 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878113+00:00 | 2017-08-10 14:08:44.648985+00:00 | 81fbdd4d-394c-4784-b540-97cd73910dba
| 2 | 1530ce8813ad694b0000000000000001 | mroach | 192.168.0.72:56201 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878306+00:00 | 2017-08-10 14:08:44.653135+00:00 | 5aa6f141-5cae-468f-b16a-dfe8d4fb4bea
| 2 | 1520ab8813ad694b0000000000000001 | mroach | 192.168.0.72:56198 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878464+00:00 | 2017-08-10 14:08:44.643749+00:00 | d8fedb88-fc21-4720-aabe-cd43ec204d88
| 3 | 1559f68813ad694b0000000000000001 | broach | 192.168.0.73:56199 | test_app | SELECT k, v FROM test.kv WHERE k = $1; | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | 2017-08-10 14:08:22.878048+00:00 | 2017-08-10 14:08:44.655709+00:00 | NULL
| 3 | 1340rd8813ad694b0000000000000001 | broach | 192.168.0.73:56196 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878166+00:00 | 2017-08-10 14:08:44.647464+00:00 | aded7717-94e1-4ac4-9d37-8765e3418e32
| 1 | 1230ab8813ad694b0000000000000001 | lroach | 192.168.0.71:56180 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.87337+00:00 | 2017-08-10 14:08:44.64788+00:00 | f691c5dd-b29e-48ed-a1dd-6d7f71faa82e
| 1 | 15234d8813ad694b0000000000000001 | lroach | 192.168.0.71:56197 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.877932+00:00 | 2017-08-10 14:08:44.644786+00:00 | 86ae25ea-9abf-4f5e-ad96-0522178f4ce6
| 1 | 14605d8813ad694b0000000000000001 | lroach | 192.168.0.71:56200 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878534+00:00 | 2017-08-10 14:08:44.653524+00:00 | 8ad972b6-4347-4128-9e52-8553f3491963
| 1 | 1965lh8813ad694b0000000000000001 | root | 127.0.0.1:56211 | cockroach | SHOW CLUSTER SESSIONS; | | 2017-08-10 14:08:27.666826+00:00 | 2017-08-10 14:08:44.653355+00:00 | NULL
+---------+----------------------------------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------+----------------------------------+----------------------------------|--------------------------------------+
(9 rows)
Alternatively, you can use SHOW SESSIONS
to receive the same response.
List active sessions on the local node
> SHOW LOCAL SESSIONS;
+---------+----------------------------------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------|----------------------------------+----------------------------------+--------------------------------------+
| node_id | session_id | user_name | client_address | application_name | active_queries | last_active_query | session_start | oldest_query_start | kv_txn |
+---------+----------------------------------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------+----------------------------------+----------------------------------+--------------------------------------|
| 1 | 1230ab8813ad694b0000000000000001 | lroach | 192.168.0.71:56180 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.87337+00:00 | 2017-08-10 14:08:44.64788+00:00 | f691c5dd-b29e-48ed-a1dd-6d7f71faa82e |
| 1 | 15234d8813ad694b0000000000000001 | lroach | 192.168.0.71:56197 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.877932+00:00 | 2017-08-10 14:08:44.644786+00:00 | 86ae25ea-9abf-4f5e-ad96-0522178f4ce6 |
| 1 | 14605d8813ad694b0000000000000001 | lroach | 192.168.0.71:56200 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878534+00:00 | 2017-08-10 14:08:44.653524+00:00 | 8ad972b6-4347-4128-9e52-8553f3491963 |
| 1 | 1965lh8813ad694b0000000000000001 | root | 127.0.0.1:56211 | cockroach | SHOW CLUSTER SESSIONS; | | 2017-08-10 14:08:27.666826+00:00 | 2017-08-10 14:08:44.653355+00:00 | NULL |
+---------+----------------------------------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------+----------------------------------+----------------------------------|--------------------------------------+
(4 rows)
Filter for specific sessions
You can use a SELECT
statement to filter the list of currently active sessions by one or more of the response fields.
Show sessions associated with a specific user
> SELECT * FROM [SHOW CLUSTER SESSIONS] WHERE user_name = 'mroach';
+---------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------|----------------------------------+----------------------------------+--------------------------------------+
| node_id | user_name | client_address | application_name | active_queries | last_active_query | session_start | oldest_query_start | kv_txn |
+---------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------+----------------------------------+----------------------------------+--------------------------------------|
| 2 | mroach | 192.168.0.72:56194 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878113+00:00 | 2017-08-10 14:08:44.648985+00:00 | 81fbdd4d-394c-4784-b540-97cd73910dba |
| 2 | mroach | 192.168.0.72:56201 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878306+00:00 | 2017-08-10 14:08:44.653135+00:00 | 5aa6f141-5cae-468f-b16a-dfe8d4fb4bea |
| 2 | mroach | 192.168.0.72:56198 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878464+00:00 | 2017-08-10 14:08:44.643749+00:00 | d8fedb88-fc21-4720-aabe-cd43ec204d88 |
+---------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------+----------------------------------+----------------------------------|--------------------------------------+
(3 rows)
Exclude sessions from the built-in SQL client
To exclude sessions from the built-in SQL client, filter for sessions that do not show cockroach
as the application_name
:
> SELECT * FROM [SHOW CLUSTER SESSIONS]
WHERE application_name != 'cockroach';
+---------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------|----------------------------------+----------------------------------+--------------------------------------+
| node_id | user_name | client_address | application_name | active_queries | last_active_query | session_start | oldest_query_start | kv_txn
+---------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------+----------------------------------+----------------------------------+--------------------------------------|
| 2 | mroach | 192.168.0.72:56194 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878113+00:00 | 2017-08-10 14:08:44.648985+00:00 | 81fbdd4d-394c-4784-b540-97cd73910dba
| 2 | mroach | 192.168.0.72:56201 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878306+00:00 | 2017-08-10 14:08:44.653135+00:00 | 5aa6f141-5cae-468f-b16a-dfe8d4fb4bea
| 2 | mroach | 192.168.0.72:56198 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878464+00:00 | 2017-08-10 14:08:44.643749+00:00 | d8fedb88-fc21-4720-aabe-cd43ec204d88
| 3 | broach | 192.168.0.73:56199 | test_app | SELECT k, v FROM test.kv WHERE k = $1; | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | 2017-08-10 14:08:22.878048+00:00 | 2017-08-10 14:08:44.655709+00:00 | NULL
| 3 | broach | 192.168.0.73:56196 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878166+00:00 | 2017-08-10 14:08:44.647464+00:00 | aded7717-94e1-4ac4-9d37-8765e3418e32
| 1 | lroach | 192.168.0.71:56180 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.87337+00:00 | 2017-08-10 14:08:44.64788+00:00 | f691c5dd-b29e-48ed-a1dd-6d7f71faa82e
| 1 | lroach | 192.168.0.71:56197 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.877932+00:00 | 2017-08-10 14:08:44.644786+00:00 | 86ae25ea-9abf-4f5e-ad96-0522178f4ce6
| 1 | lroach | 192.168.0.71:56200 | test_app | UPSERT INTO test.kv(k, v) VALUES ($1, $2); | SELECT k, v FROM test.kv WHERE k = $1; | 2017-08-10 14:08:22.878534+00:00 | 2017-08-10 14:08:44.653524+00:00 | 8ad972b6-4347-4128-9e52-8553f3491963
+---------+-----------+--------------------+------------------+---------------------------------------------+--------------------------------------------+----------------------------------+----------------------------------|--------------------------------------+
(8 rows)
Identify and cancel a problematic query
If a session has been open for a long time and you are concerned that the oldest active SQL query may be problematic, you can use the SHOW QUERIES
statement to further investigate the query and then, if necessary, use the CANCEL QUERY
statement to cancel it.
For example, let's say you run SHOW SESSIONS
and notice that the following session has been open for more than 2 hours:
+---------+----------+--------------------+------------------+------------------------------------+--------------------|----------------------------------+----------------------------------+--------+
| node_id | user_name | client_address | application_name | active_queries | last_active_query | session_start | oldest_query_start | kv_txn
+---------+-----------+--------------------+------------------+------------------------------------+--------------------+----------------------------------+----------------------------------|--------+
| 2 | mroach | 192.168.0.72:56194 | test_app | SELECT * FROM test.kv ORDER BY k; | | 2017-08-10 14:08:22.878113+00:00 | 2017-08-10 14:08:22.878113+00:00 | NULL
+---------+-----------+--------------------+------------------+------------------------------------+--------------------|----------------------------------+----------------------------------+--------+
Since the oldest_query_start
timestamp is the same as the session_start
timestamp, you are concerned that the SELECT
query shown in active_queries
has been running for too long and may be consuming too many resources. So you use the SHOW QUERIES
statement to get more information about the query, filtering based on details you already have:
> SELECT * FROM [SHOW CLUSTER QUERIES]
WHERE client_address = '192.168.0.72:56194'
AND user_name = 'mroach'
AND query = 'SELECT * FROM test.kv ORDER BY k';
+----------------------------------+---------+-----------+----------------------------------+----------------------------------+--------------------+------------------+-------------+-----------+
| query_id | node_id | user_name | start | query | client_address | application_name | distributed | phase |
+----------------------------------+---------+-----------+----------------------------------+----------------------------------+--------------------+------------------+-------------+-----------+
| 14dacc1f9a781e3d0000000000000001 | 2 | mroach | 2017-08-10 14:08:22.878113+00:00 | SELECT * FROM test.kv ORDER BY k | 192.168.0.72:56194 | test_app | false | executing |
+----------------------------------+---------+-----------+----------------------------------+----------------------------------+--------------------+------------------+-------------+-----------+
Using the start
field, you confirm that the query has been running since the start of the session and decide that is too long. So to cancel the query, and stop it from consuming resources, you note the query_id
and use it with the CANCEL QUERY
statement:
> CANCEL QUERY '14dacc1f9a781e3d0000000000000001';
Alternatively, if you know that you want to cancel the query based on the details in SHOW SESSIONS
, you could execute a single CANCEL QUERY
statement with a nested SELECT
statement that returns the query_id
:
> CANCEL QUERY (SELECT query_id FROM [SHOW CLUSTER QUERIES]
WHERE client_address = '192.168.0.72:56194'
AND user_name = 'mroach'
AND query = 'SELECT * FROM test.kv ORDER BY k');