Querying Configuration Parameters

Function

This API is used to query the configuration parameters of a DCS instance.

URI

GET /v1.0/{project_id}/instances/{instance_id}/configs

Table 1 describes the parameters.

Table 1 Parameter description

Parameter

Type

Mandatory

Description

project_id

String

Yes

Project ID. For details on how to obtain the value of this parameter, see Obtaining a Project ID.

instance_id

String

Yes

ID of the instance to be queried.

Request

Request parameters

None

Example request

GET https://{dcs_endpoint}/v1.0/{project_id}/instances/{instance_id}/configs

Response

Response parameters

Table 2 describes the response parameters.

Table 2 Parameter description

Parameter

Type

Description

status

String

Current status of a DCS instance.

instance_id

String

DCS instance ID.

redis_config

Array

Array of configuration items of the DCS instance. For details, see Table 3.

config_status

String

DCS instance status that is being modified or has been modified. Options:

  • UPDATING

  • FAILURE

  • SUCCESS

config_time

String

Time at which the DCS instance is operated on. For example, 2017-03-31T12:24:46.297Z.

cluster_v1

Boolean

Instance type. If true is returned, the instance is a Proxy Cluster DCS Redis 3.0 instance. If false is returned, the instance is not a Proxy Cluster DCS Redis 3.0 instance.

Table 3 redis_config parameter description

Parameter

Type

Description

description

String

Configuration item description.

param_id

String

Configuration parameter ID. For the possible values, see the Parameter ID column in Table 4.

param_name

String

Configuration parameter name. For the possible values, see the Parameter Name column in Table 4.

param_value

String

Configuration parameter value.

default_value

String

Default value of the configuration parameter. For the possible values, see the Default Value column in Table 4.

value_type

String

Type of the configuration parameter value. For the possible values, see the Value Type column in Table 4.

value_range

String

Range of the configuration parameter value. For the possible values, see the Value Range column in Table 4.

node_role

String

If null or empty is returned, the node is a default node, that is, the Redis Server node. If proxy is returned, the node is a proxy node.

Table 4 describes the configuration parameters of a DCS instance.

Table 4 Configuration parameters of a DCS instance

Parameter ID

Parameter Name

Type

Description

Value Range

Default Value

1

timeout

Integer

Connection between the client and server (DCS instance) will be closed if the client is idle for the timeout period (measured in seconds). A timeout period of 0 seconds indicates that the timeout function is disabled.

0-7200 seconds

0

2

maxmemory-policy

String

How Redis will select what to remove when maxmemory is reached.

For details about key eviction, see the Redis official website.

volatile-lru

allkeys-lru

volatile-random

allkeys-random

volatile-ttl

noeviction

volatile-lfu

allkeys-lfu

noeviction or volatile-lru

The value range and default value depend on the instance version and type.

3

hash-max-ziplist-entries

Integer

When the number of entries in hashes is less than the value of this parameter, hashes are encoded using ziplist to save memory.

1-10,000

512

4

hash-max-ziplist-value

Integer

When the biggest entry in hashes does not exceed the length threshold indicated by this parameter, hashes are encoded using ziplist to save memory.

1-10,000

64

5

list-max-ziplist-entries

Integer

When the number of entries in lists is less than the value of this parameter, lists are encoded using ziplist to save memory.

1-10,000

512

6

list-max-ziplist-value

Integer

When the biggest entry in lists does not exceed the length threshold indicated by this parameter, lists are encoded using ziplist to save memory.

1-10,000

64

7

set-max-intset-entries

Integer

When a set is composed entirely of strings and the number of integers does not exceed the length threshold indicated by this parameter, the set is encoded using intset to save memory.

1-10,000

512

8

zset-max-ziplist-entries

Integer

When the number of entries in sorted sets is less than the value of this parameter, sorted sets are encoded using a memory efficient data structure.

1-10,000

128

9

zset-max-ziplist-value

Integer

When the biggest entry in sorted sets does not exceed the length threshold indicated by this parameter, sorted sets are encoded using ziplist to save memory.

1-10,000

64

10

latency-monitor-threshold

IntegerInteger

The minimum amount of latency that will be logged as latency spikes

If this parameter is set to 0, latency monitoring is disabled. If this parameter is set to a value greater than 0, all events blocking the server for a time greater than the configured value will be logged.

By running the LATENCY command, you can perform operations related to latency monitoring, such as obtaining statistical data, and configuring and enabling latency monitoring. For more information about the latency-monitor-threshold, visit the Redis official website.

0-86,400,000 ms

0

11

maxclients

Integer

The maximum number of clients allowed to be concurrently connected to a DCS instance.

1000-50,000

10,000

12

reserved-memory

Integer

Reserved memory, which is the number of megabytes reserved for the backend to perform internal processing such as persistence and master/standby replication.

This parameter is available only for master/standby instances.

The size of the reserved memory can be adjusted, but must be in the value range described in the next column. For more information about maximum available memory of each instance type, see Distributed Cache Service User Guide.

0% to 50% of maximum memory space initially available to the instance and below the current free memory space. Unit: MB.

0

13

notify-keyspace-events

String

Keyspace event notification. If this parameter is configured, the Redis Sub/Pub feature will allow clients to receive an event when a Redis data set is modified.

If the parameter value contains multiple characters, keyspace event notification is enabled and each character identifies a class of keyspace events for which Redis will send notifications.

K: Keyspace events, published with the __keyspace@__ prefix

E: Keyevent events, published with the __keyevent@__ prefix

g: Generic commands (non-type specific) such as DEL, EXPIRE, and RENAME

$: String commands

l: List commands

s: Set commands

h: Hash commands

z: Sorted set commands

x: Expired events (events generated every time a key expires)

e: Evicted events (events generated when a key is evicted for maxmemory)

For more information, see the following note.

Ex

14

repl-backlog-size

Integer

The replication backlog size in bytes. The backlog is a buffer that accumulates replica data when replicas are disconnected from the master. When a replica reconnects, a partial synchronization is performed to synchronize the data that was missed while replicas were disconnected.

16,384-1,073,741,824

1,048,576

15

repl-backlog-ttl

Integer

The amount of time, in seconds, before the backlog buffer is released, starting from the last a replica was disconnected. The value 0 indicates that the backlog is never released.

0-604,800

3600

16

appendfsync

String

Controls how often fsync() transfers cached data to the disk. Note that some OSs will perform a complete data transfer but some others only make a "best-effort" attempt.

Redis calls fsync() in one of the following ways:

no: fsync() is never called. The OS will flush data when it is ready. This mode offers the highest performance.

always: fsync() is called after every write to the AOF. This mode is very slow, but also very safe. everysec: fsync() is called once per second. This mode provides a compromise between safety and performance.

everysec

17

appendonly

String

Indicates whether to log each modification of the instance. By default, data is written to disks asynchronously in Redis. If this function is disabled, recently-generated data might be lost in the event of a power failure.

yes,no

yes

18

slowlog-log-slower-than

Integer

Redis uses the slow log to record queries that exceed a specified execution time. slowlog-log-slower-than is the maximum time allowed, in microseconds, for command execution. If this threshold is exceeded, Slow Log will record the command.

0-1,000,000

10,000

19

slowlog-max-len

Integer

The maximum allowed length of the Redis Slow Log logs. Slow Log consumes memory, but you can reclaim this memory by running the SLOWLOG RESET command.

0-1000

128

20

lua-time-limit

Integer

The maximum time allowed for executing a Lua script, in milliseconds.

100-5000

5000

21

repl-timeout

Integer

Replication timeout, in seconds.

30-3600

60

22

proto-max-bulk-len

Integer

The maximum size (in bytes) of a single element request.

1,048,576-536,870,912

536,870,912

23

master-read-only

String

Sets the instance to be read-only. All write operations will fail.

yes,no

no

24

client-output-buffer-slave-soft-limit

Integer

Soft limit (in bytes) on the output buffer of replica clients. Once the output buffer exceeds the soft limit and continuously remains above the limit for the time specified by the client-output-buffer-limit-slave-soft-seconds parameter, the client is disconnected.

0-134,217,728

13,421,772

25

client-output-buffer-slave-hard-limit

Integer

Hard limit (in bytes) on the output buffer of replica clients. Once the output buffer exceeds the hard limit, the client is immediately disconnected.

0-134,217,728

13,421,772

26

client-output-buffer-limit-slave-soft-seconds

Integer

Number of seconds that the output buffer remains above client-output-buffer-slave-soft-limit before the client is disconnected.

0-60

60

30

reserved-memory-percent

Integer

Percentage of memory reserved for non-cache memory usage.

0-80

0

Table 5, Table 6, Table 7, Table 8, Table 9, and Table 10 describe the configuration parameters of different DCS instances.

Table 5 Configuration parameters of a single-node DCS Redis 3.0 instance

Instance Type

Parameter ID

Parameter Name

Type

Description

Value Range

Default Value

Single-node Redis 3.0

1

timeout

Integer

Connection between the client and server (DCS instance) will be closed if the client is idle for the timeout period (measured in seconds). A timeout period of 0 seconds indicates that the timeout function is disabled.

0-7200 seconds

0

2

maxmemory-policy

String

How Redis will select what to remove when maxmemory is reached.

For details about key eviction, see the Redis official website.

volatile-lru

allkeys-lru

volatile-random

allkeys-random

volatile-ttl

noeviction

noeviction

3

hash-max-ziplist-entries

Integer

When the number of entries in hashes is less than the value of this parameter, hashes are encoded using ziplist to save memory.

1-10,000

512

4

hash-max-ziplist-value

Integer

When the biggest entry in hashes does not exceed the length threshold indicated by this parameter, hashes are encoded using ziplist to save memory.

1-10,000

64

5

list-max-ziplist-entries

Integer

When the number of entries in lists is less than the value of this parameter, lists are encoded using ziplist to save memory.

1-10,000

512

6

list-max-ziplist-value

Integer

When the biggest entry in lists does not exceed the length threshold indicated by this parameter, lists are encoded using ziplist to save memory.

1-10,000

64

7

set-max-intset-entries

Integer

When a set is composed entirely of strings and the number of integers does not exceed the length threshold indicated by this parameter, the set is encoded using intset to save memory.

1-10,000

512

8

zset-max-ziplist-entries

Integer

When the number of entries in sorted sets is less than the value of this parameter, sorted sets are encoded using a memory efficient data structure.

1-10,000

128

9

zset-max-ziplist-value

Integer

When the biggest entry in sorted sets does not exceed the length threshold indicated by this parameter, sorted sets are encoded using ziplist to save memory.

1-10,000

64

10

latency-monitor-threshold

Integer

The minimum amount of latency that will be logged as latency spikes

If this parameter is set to 0, latency monitoring is disabled. If this parameter is set to a value greater than 0, all events blocking the server for a time greater than the configured value will be logged.

By running the LATENCY command, you can perform operations related to latency monitoring, such as obtaining statistical data, and configuring and enabling latency monitoring. For more information about the latency-monitor-threshold, visit the Redis official website.

0-86,400,000 ms

0

13

notify-keyspace-events

String

Keyspace event notification. If this parameter is configured, the Redis Sub/Pub feature will allow clients to receive an event when a Redis data set is modified.

If the parameter value contains multiple characters, keyspace event notification is enabled and each character identifies a class of keyspace events for which Redis will send notifications.

K: Keyspace events, published with the __keyspace@__ prefix

E: Keyevent events, published with the __keyevent@__ prefix

g: Generic commands (non-type specific) such as DEL, EXPIRE, and RENAME

$: String commands

l: List commands

s: Set commands

h: Hash commands

z: Sorted set commands

x: Expired events (events generated every time a key expires)

e: Evicted events (events generated when a key is evicted for maxmemory)

For more information, see the note below the table.

Ex

18

slowlog-log-slower-than

Integer

Redis uses the slow log to record queries that exceed a specified execution time. slowlog-log-slower-than is the maximum time allowed, in microseconds, for command execution. If this threshold is exceeded, Slow Log will record the command.

0-1,000,000

10,000

19

slowlog-max-len

Integer

The maximum allowed length of the Redis Slow Log logs. Slow Log consumes memory, but you can reclaim this memory by running the SLOWLOG RESET command.

0-1000

128

30

reserved-memory-percent

Integer

Percentage of memory reserved for non-cache memory usage.

0-80

0

Table 6 Configuration parameters of a master/standby DCS Redis 3.0 instance

Instance Type

Parameter ID

Parameter Name

Type

Description

Value Range

Default Value

Master/standby Redis 3.0

1

timeout

Integer

Connection between the client and server (DCS instance) will be closed if the client is idle for the timeout period (measured in seconds). A timeout period of 0 seconds indicates that the timeout function is disabled.

0-7200 seconds

0

2

maxmemory-policy

String

How Redis will select what to remove when maxmemory is reached.

For details about key eviction, see the Redis official website.

volatile-lru

allkeys-lru

volatile-random

allkeys-random

volatile-ttl

noeviction

noeviction

3

hash-max-ziplist-entries

Integer

When the number of entries in hashes is less than the value of this parameter, hashes are encoded using ziplist to save memory.

1-10,000

512

4

hash-max-ziplist-value

Integer

When the biggest entry in hashes does not exceed the length threshold indicated by this parameter, hashes are encoded using ziplist to save memory.

1-10,000

64

5

list-max-ziplist-entries

Integer

When the number of entries in lists is less than the value of this parameter, lists are encoded using ziplist to save memory.

1-10,000

512

6

list-max-ziplist-value

Integer

When the biggest entry in lists does not exceed the length threshold indicated by this parameter, lists are encoded using ziplist to save memory.

1-10,000

64

7

set-max-intset-entries

Integer

When a set is composed entirely of strings and the number of integers does not exceed the length threshold indicated by this parameter, the set is encoded using intset to save memory.

1-10,000

512

8

zset-max-ziplist-entries

Integer

When the number of entries in sorted sets is less than the value of this parameter, sorted sets are encoded using a memory efficient data structure.

1-10,000

128

9

zset-max-ziplist-value

Integer

When the biggest entry in sorted sets does not exceed the length threshold indicated by this parameter, sorted sets are encoded using ziplist to save memory.

1-10,000

64

10

latency-monitor-threshold

Integer

The minimum amount of latency that will be logged as latency spikes

If this parameter is set to 0, latency monitoring is disabled. If this parameter is set to a value greater than 0, all events blocking the server for a time greater than the configured value will be logged.

By running the LATENCY command, you can perform operations related to latency monitoring, such as obtaining statistical data, and configuring and enabling latency monitoring. For more information about the latency-monitor-threshold, visit the Redis official website.

0-86,400,000 ms

0

13

notify-keyspace-events

String

Keyspace event notification. If this parameter is configured, the Redis Sub/Pub feature will allow clients to receive an event when a Redis data set is modified.

If the parameter value contains multiple characters, keyspace event notification is enabled and each character identifies a class of keyspace events for which Redis will send notifications.

K: Keyspace events, published with the __keyspace@__ prefix

E: Keyevent events, published with the __keyevent@__ prefix

g: Generic commands (non-type specific) such as DEL, EXPIRE, and RENAME

$: String commands

l: List commands

s: Set commands

h: Hash commands

z: Sorted set commands

x: Expired events (events generated every time a key expires)

e: Evicted events (events generated when a key is evicted for maxmemory)

For more information, see the following note.

Ex

14

repl-backlog-size

Integer

The replication backlog size in bytes. The backlog is a buffer that accumulates replica data when replicas are disconnected from the master. When a replica reconnects, a partial synchronization is performed to synchronize the data that was missed while replicas were disconnected.

16,384-1,073,741,824

1,048,576

15

repl-backlog-ttl

Integer

The amount of time, in seconds, before the backlog buffer is released, starting from the last a replica was disconnected. The value 0 indicates that the backlog is never released.

0-604,800

3600

16

appendfsync

String

Controls how often fsync() transfers cached data to the disk. Note that some OSs will perform a complete data transfer but some others only make a "best-effort" attempt.

Redis calls fsync() in one of the following ways:

no: fsync() is never called. The OS will flush data when it is ready. This mode offers the highest performance.

always: fsync() is called after every write to the AOF. This mode is very slow, but also very safe. everysec: fsync() is called once per second. This mode provides a compromise between safety and performance.

everysec

17

appendonly

String

Indicates whether to log each modification of the instance. By default, data is written to disks asynchronously in Redis. If this function is disabled, recently-generated data might be lost in the event of a power failure.

yes,no

yes

18

slowlog-log-slower-than

Integer

Redis uses the slow log to record queries that exceed a specified execution time. slowlog-log-slower-than is the maximum time allowed, in microseconds, for command execution. If this threshold is exceeded, Slow Log will record the command.

0-1,000,000

10,000

19

slowlog-max-len

Integer

The maximum allowed length of the Redis Slow Log logs. Slow Log consumes memory, but you can reclaim this memory by running the SLOWLOG RESET command.

0-1000

128

30

reserved-memory-percent

Integer

Percentage of memory reserved for non-cache memory usage.

0-80

0

Table 7 Configuration parameters of a Proxy Cluster DCS Redis 3.0 instance

Instance Type

Parameter ID

Parameter Name

Type

Description

Value Range

Default Value

Proxy Cluster Redis 3.0

2

maxmemory-policy

String

How Redis will select what to remove when maxmemory is reached.

For details about key eviction, see the Redis official website.

volatile-lru

allkeys-lru

volatile-random

allkeys-random

volatile-ttl

noeviction

volatile-lru

Table 8 Configuration parameters of a single-node DCS Redis 4.0 or 5.0 instance

Instance Type

Parameter ID

Parameter Name

Type

Description

Value Range

Default Value

Single-node Redis 4.0 or 5.0

1

timeout

Integer

Connection between the client and server (DCS instance) will be closed if the client is idle for the timeout period (measured in seconds). A timeout period of 0 seconds indicates that the timeout function is disabled.

0-7200 seconds

0

2

maxmemory-policy

String

How Redis will select what to remove when maxmemory is reached.

For details about key eviction, see the Redis official website.

volatile-lru

allkeys-lru

volatile-random

allkeys-random

volatile-ttl

noeviction

volatile-lfu

allkeys-lfu

volatile-lru

3

hash-max-ziplist-entries

Integer

When the number of entries in hashes is less than the value of this parameter, hashes are encoded using ziplist to save memory.

1-10,000

512

4

hash-max-ziplist-value

Integer

When the biggest entry in hashes does not exceed the length threshold indicated by this parameter, hashes are encoded using ziplist to save memory.

1-10,000

64

7

set-max-intset-entries

Integer

When a set is composed entirely of strings and the number of integers does not exceed the length threshold indicated by this parameter, the set is encoded using intset to save memory.

1-10,000

512

8

zset-max-ziplist-entries

Integer

When the number of entries in sorted sets is less than the value of this parameter, sorted sets are encoded using a memory efficient data structure.

1-10,000

128

9

zset-max-ziplist-value

Integer

When the biggest entry in sorted sets does not exceed the length threshold indicated by this parameter, sorted sets are encoded using ziplist to save memory.

1-10,000

64

10

latency-monitor-threshold

Integer

The minimum amount of latency that will be logged as latency spikes

If this parameter is set to 0, latency monitoring is disabled. If this parameter is set to a value greater than 0, all events blocking the server for a time greater than the configured value will be logged.

By running the LATENCY command, you can perform operations related to latency monitoring, such as obtaining statistical data, and configuring and enabling latency monitoring. For more information about the latency-monitor-threshold, visit the Redis official website.

0-86,400,000 ms

0

11

maxclients

Integer

The maximum number of clients allowed to be concurrently connected to a DCS instance.

1000-50,000

10,000

13

notify-keyspace-events

String

Keyspace event notification. If this parameter is configured, the Redis Sub/Pub feature will allow clients to receive an event when a Redis data set is modified.

If the parameter value contains multiple characters, keyspace event notification is enabled and each character identifies a class of keyspace events for which Redis will send notifications.

K: Keyspace events, published with the __keyspace@__ prefix

E: Keyevent events, published with the __keyevent@__ prefix

g: Generic commands (non-type specific) such as DEL, EXPIRE, and RENAME

$: String commands

l: List commands

s: Set commands

h: Hash commands

z: Sorted set commands

x: Expired events (events generated every time a key expires)

e: Evicted events (events generated when a key is evicted for maxmemory)

For more information, see the following note.

Ex

18

slowlog-log-slower-than

Integer

Redis uses the slow log to record queries that exceed a specified execution time. slowlog-log-slower-than is the maximum time allowed, in microseconds, for command execution. If this threshold is exceeded, Slow Log will record the command.

0-1,000,000

10,000

19

slowlog-max-len

Integer

The maximum allowed length of the Redis Slow Log logs. Slow Log consumes memory, but you can reclaim this memory by running the SLOWLOG RESET command.

0-1000

128

20

lua-time-limit

Integer

The maximum time allowed for executing a Lua script, in milliseconds.

100-5000

5000

22

proto-max-bulk-len

Integer

The maximum size (in bytes) of a single element request.

1,048,576-536,870,912

536,870,912

23

master-read-only

String

Sets the instance to be read-only. All write operations will fail.

yes,no

no

Table 9 Configuration parameters of a master/standby DCS Redis 4.0 or 5.0 instance

Instance Type

Parameter ID

Parameter Name

Type

Description

Value Range

Default Value

Master/standby Redis 4.0 or 5.0

1

timeout

Integer

Connection between the client and server (DCS instance) will be closed if the client is idle for the timeout period (measured in seconds). A timeout period of 0 seconds indicates that the timeout function is disabled.

0-7200 seconds

0

2

maxmemory-policy

String

How Redis will select what to remove when maxmemory is reached.

For details about key eviction, see the Redis official website.

volatile-lru

allkeys-lru

volatile-random

allkeys-random

volatile-ttl

noeviction

volatile-lfu

allkeys-lfu

volatile-lru

3

hash-max-ziplist-entries

Integer

When the number of entries in hashes is less than the value of this parameter, hashes are encoded using ziplist to save memory.

1-10,000

512

4

hash-max-ziplist-value

Integer

When the biggest entry in hashes does not exceed the length threshold indicated by this parameter, hashes are encoded using ziplist to save memory.

1-10,000

64

7

set-max-intset-entries

Integer

When a set is composed entirely of strings and the number of integers does not exceed the length threshold indicated by this parameter, the set is encoded using intset to save memory.

1-10,000

512

8

zset-max-ziplist-entries

Integer

When the number of entries in sorted sets is less than the value of this parameter, sorted sets are encoded using a memory efficient data structure.

1-10,000

128

9

zset-max-ziplist-value

Integer

When the biggest entry in sorted sets does not exceed the length threshold indicated by this parameter, sorted sets are encoded using ziplist to save memory.

1-10,000

64

10

latency-monitor-threshold

Integer

The minimum amount of latency that will be logged as latency spikes

If this parameter is set to 0, latency monitoring is disabled. If this parameter is set to a value greater than 0, all events blocking the server for a time greater than the configured value will be logged.

By running the LATENCY command, you can perform operations related to latency monitoring, such as obtaining statistical data, and configuring and enabling latency monitoring. For more information about the latency-monitor-threshold, visit the Redis official website.

0-86,400,000 ms

0

11

maxclients

Integer

The maximum number of clients allowed to be concurrently connected to a DCS instance.

1000-50,000

10,000

13

notify-keyspace-events

String

Keyspace event notification. If this parameter is configured, the Redis Sub/Pub feature will allow clients to receive an event when a Redis data set is modified.

If the parameter value contains multiple characters, keyspace event notification is enabled and each character identifies a class of keyspace events for which Redis will send notifications.

K: Keyspace events, published with the __keyspace@__ prefix

E: Keyevent events, published with the __keyevent@__ prefix

g: Generic commands (non-type specific) such as DEL, EXPIRE, and RENAME

$: String commands

l: List commands

s: Set commands

h: Hash commands

z: Sorted set commands

x: Expired events (events generated every time a key expires)

e: Evicted events (events generated when a key is evicted for maxmemory)

For more information, see the note below the table.

Ex

14

repl-backlog-size

Integer

The replication backlog size in bytes. The backlog is a buffer that accumulates replica data when replicas are disconnected from the master. When a replica reconnects, a partial synchronization is performed to synchronize the data that was missed while replicas were disconnected.

16,384-1,073,741,824

1,048,576

15

repl-backlog-ttl

IntegerInteger

The amount of time, in seconds, before the backlog buffer is released, starting from the last a replica was disconnected. The value 0 indicates that the backlog is never released.

0-604,800

3600

16

appendfsync

String

Controls how often fsync() transfers cached data to the disk. Note that some OSs will perform a complete data transfer but some others only make a "best-effort" attempt.

Redis calls fsync() in one of the following ways:

no: fsync() is never called. The OS will flush data when it is ready. This mode offers the highest performance.

always: fsync() is called after every write to the AOF. This mode is very slow, but also very safe. everysec: fsync() is called once per second. This mode provides a compromise between safety and performance.

everysec

17

appendonly

String

Indicates whether to log each modification of the instance. By default, data is written to disks asynchronously in Redis. If this function is disabled, recently-generated data might be lost in the event of a power failure.

yes,no

yes

18

slowlog-log-slower-than

Integer

Redis uses the slow log to record queries that exceed a specified execution time. slowlog-log-slower-than is the maximum time allowed, in microseconds, for command execution. If this threshold is exceeded, Slow Log will record the command.

0-1,000,000

10,000

19

slowlog-max-len

Integer

The maximum allowed length of the Redis Slow Log logs. Slow Log consumes memory, but you can reclaim this memory by running the SLOWLOG RESET command.

0-1000

128

20

lua-time-limit

Integer

The maximum time allowed for executing a Lua script, in milliseconds.

100-5000

5000

21

repl-timeout

Integer

Replication timeout, in seconds.

30-3600

60

22

proto-max-bulk-len

Integer

The maximum size (in bytes) of a single element request.

1,048,576-536,870,912

536,870,912

23

master-read-only

String

Sets the instance to be read-only. All write operations will fail.

yes,no

no

24

client-output-buffer-slave-soft-limit

Integer

Soft limit (in bytes) on the output buffer of replica clients. Once the output buffer exceeds the soft limit and continuously remains above the limit for the time specified by the client-output-buffer-limit-slave-soft-seconds parameter, the client is disconnected.

0-134,217,728

13,421,772

25

client-output-buffer-slave-hard-limit

Integer

Hard limit (in bytes) on the output buffer of replica clients. Once the output buffer exceeds the hard limit, the client is immediately disconnected.

0-134,217,728

13,421,772

26

client-output-buffer-limit-slave-soft-seconds

Integer

Number of seconds that the output buffer remains above client-output-buffer-slave-soft-limit before the client is disconnected.

0-60

60

Table 10 Configuration parameters of a Redis Cluster DCS Redis 4.0 or 5.0 instance

Instance Type

Parameter ID

Parameter Name

Type

Description

Value Range

Default Value

Redis 4.0 or 5.0 Redis cluster

1

timeout

Integer

Connection between the client and server (DCS instance) will be closed if the client is idle for the timeout period (measured in seconds). A timeout period of 0 seconds indicates that the timeout function is disabled.

0-7200 seconds

0

2

maxmemory-policy

String

How Redis will select what to remove when maxmemory is reached.

For details about key eviction, see the Redis official website.

volatile-lru

allkeys-lru

volatile-random

allkeys-random

volatile-ttl

noeviction

volatile-lfu

allkeys-lfu

volatile-lru

3

hash-max-ziplist-entries

Integer

When the number of entries in hashes is less than the value of this parameter, hashes are encoded using ziplist to save memory.

1-10,000

512

4

hash-max-ziplist-value

Integer

When the biggest entry in hashes does not exceed the length threshold indicated by this parameter, hashes are encoded using ziplist to save memory.

1-10,000

64

7

set-max-intset-entries

Integer

When a set is composed entirely of strings and the number of integers does not exceed the length threshold indicated by this parameter, the set is encoded using intset to save memory.

1-10,000

512

8

zset-max-ziplist-entries

Integer

When the number of entries in sorted sets is less than the value of this parameter, sorted sets are encoded using a memory efficient data structure.

1-10,000

128

9

zset-max-ziplist-value

Integer

When the biggest entry in sorted sets does not exceed the length threshold indicated by this parameter, sorted sets are encoded using ziplist to save memory.

1-10,000

64

10

latency-monitor-threshold

Integer

The minimum amount of latency that will be logged as latency spikes

If this parameter is set to 0, latency monitoring is disabled. If this parameter is set to a value greater than 0, all events blocking the server for a time greater than the configured value will be logged.

By running the LATENCY command, you can perform operations related to latency monitoring, such as obtaining statistical data, and configuring and enabling latency monitoring. For more information about the latency-monitor-threshold, visit the Redis official website.

0-86,400,000 ms

0

11

maxclients

Integer

The maximum number of clients allowed to be concurrently connected to a DCS instance.

1000-50,000

10,000

13

notify-keyspace-events

String

Keyspace event notification. If this parameter is configured, the Redis Sub/Pub feature will allow clients to receive an event when a Redis data set is modified.

If the parameter value contains multiple characters, keyspace event notification is enabled and each character identifies a class of keyspace events for which Redis will send notifications.

K: Keyspace events, published with the __keyspace@__ prefix

E: Keyevent events, published with the __keyevent@__ prefix

g: Generic commands (non-type specific) such as DEL, EXPIRE, and RENAME

$: String commands

l: List commands

s: Set commands

h: Hash commands

z: Sorted set commands

x: Expired events (events generated every time a key expires)

e: Evicted events (events generated when a key is evicted for maxmemory)

For more information, see the note below the table.

Ex

14

repl-backlog-size

Integer

The replication backlog size in bytes. The backlog is a buffer that accumulates replica data when replicas are disconnected from the master. When a replica reconnects, a partial synchronization is performed to synchronize the data that was missed while replicas were disconnected.

16,384-1,073,741,824

1,048,576

15

repl-backlog-ttl

Integer

The amount of time, in seconds, before the backlog buffer is released, starting from the last a replica was disconnected. The value 0 indicates that the backlog is never released.

0-604,800

3600

16

appendfsync

String

Controls how often fsync() transfers cached data to the disk. Note that some OSs will perform a complete data transfer but some others only make a "best-effort" attempt.

Redis calls fsync() in one of the following ways:

no: fsync() is never called. The OS will flush data when it is ready. This mode offers the highest performance.

always: fsync() is called after every write to the AOF. This mode is very slow, but also very safe. everysec: fsync() is called once per second. This mode provides a compromise between safety and performance.

everysec

17

appendonly

String

Indicates whether to log each modification of the instance. By default, data is written to disks asynchronously in Redis. If this function is disabled, recently-generated data might be lost in the event of a power failure.

yes,no

yes

18

slowlog-log-slower-than

Integer

Redis uses the slow log to record queries that exceed a specified execution time. slowlog-log-slower-than is the maximum time allowed, in microseconds, for command execution. If this threshold is exceeded, Slow Log will record the command.

0-1,000,000

10,000

19

slowlog-max-len

Integer

The maximum allowed length of the Redis Slow Log logs. Slow Log consumes memory, but you can reclaim this memory by running the SLOWLOG RESET command.

0-1000

128

20

lua-time-limit

Integer

The maximum time allowed for executing a Lua script, in milliseconds.

100-5000

5000

21

repl-timeout

Integer

Replication timeout, in seconds.

30-3600

60

22

proto-max-bulk-len

Integer

The maximum size (in bytes) of a single element request.

1,048,576-536,870,912

536,870,912

23

master-read-only

String

Sets the instance to be read-only. All write operations will fail.

yes,no

no

24

client-output-buffer-slave-soft-limit

Integer

Soft limit (in bytes) on the output buffer of replica clients. Once the output buffer exceeds the soft limit and continuously remains above the limit for the time specified by the client-output-buffer-limit-slave-soft-seconds parameter, the client is disconnected.

0-134,217,728

13,421,772

25

client-output-buffer-slave-hard-limit

Integer

Hard limit (in bytes) on the output buffer of replica clients. Once the output buffer exceeds the hard limit, the client is immediately disconnected.

0-134,217,728

13,421,772

26

client-output-buffer-limit-slave-soft-seconds

Integer

Number of seconds that the output buffer remains above client-output-buffer-slave-soft-limit before the client is disconnected.

0-60

60

Note

More about the notify-keyspace-events parameter:

  • Allowed characters are K, E, KE, A, g, l, s, h, z, x, e, and $. The parameter value must contain either K or E.

  • A is an alias for g$lshzxe and cannot be used together with any of the characters in g$lshzxe.

  • For example, the value Kl means that Redis will notify Pub/Sub clients about keyspace events and list commands. The value AKE means Redis will notify Pub/Sub clients about all events.

Example response

{
    "status": "RUNNING",
    "instance_id": "c08fdc6e-5c25-4185-ab57-c0a5529b727f",
    "redis_config": [
        {
            "description": "How Redis will select what to remove when maxmemory is reached, You can select among five behaviors: volatile-lru : remove the key with an expire set using an LRU algorithm allkeys-lru : remove any key according to the LRU algorithm volatile-random: remove a random key with an expire set allkeys-random: remove a random key, any key volatile-ttl : remove the key with the nearest expire time (minor TTL) noeviction : don't expire at all, just return an error on write operations",
            "param_id": 2,
            "param_name": "maxmemory-policy",
            "param_value": "noeviction",
            "default_value": "noeviction",
            "value_type": "String",
            "value_range": "volatile-lru,allkeys-lru,volatile-random,allkeys-random,volatile-ttl,noeviction"
        },
        {
            "description": "Hashes are encoded using a memory efficient data structure when they have a small number of entries",
            "param_id": 3,
            "param_name": "hash-max-ziplist-entries",
            "param_value": "512",
            "default_value": "512",
            "value_type": "Integer",
            "value_range": "1-10000"
        },
        {
            "description": "Hashes are encoded using a memory efficient data structure when the biggest entry does not exceed a given threshold",
            "param_id": 4,
            "param_name": "hash-max-ziplist-value",
            "param_value": "64",
            "default_value": "64",
            "value_type": "Integer",
            "value_range": "1-10000"
        },
        {
            "description": "Lists are encoded using a memory efficient data structure when they have a small number of entries",
            "param_id": 5,
            "param_name": "list-max-ziplist-entries",
            "param_value": "512",
            "default_value": "512",
            "value_type": "Integer",
            "value_range": "1-10000"
        },
        {
            "description": "Lists are encoded using a memory efficient data structure when the biggest entry does not exceed a given threshold",
            "param_id": 6,
            "param_name": "list-max-ziplist-value",
            "param_value": "64",
            "default_value": "64",
            "value_type": "Integer",
            "value_range": "1-10000"
        },
        {
            "description": "When a set is composed of just strings that happen to be integers in radix 10 in the range of 64 bit signed integers.",
            "param_id": 7,
            "param_name": "set-max-intset-entries",
            "param_value": "512",
            "default_value": "512",
            "value_type": "Integer",
            "value_range": "1-10000"
        },
        {
            "description": "Sorted sets are encoded using a memory efficient data structure when they have a small number of entries",
            "param_id": 8,
            "param_name": "zset-max-ziplist-entries",
            "param_value": "128",
            "default_value": "128",
            "value_type": "Integer",
            "value_range": "1-10000"
        },
        {
            "description": "Sorted sets are encoded using a memory efficient data structure when the biggest entry does not exceed a given threshold",
            "param_id": 9,
            "param_name": "zset-max-ziplist-value",
            "param_value": "64",
            "default_value": "64",
            "value_type": "Integer",
            "value_range": "1-10000"
        },
        {
            "description": "Close the connection after a client is idle for N seconds (0 to disable)",
            "param_id": 1,
            "param_name": "timeout",
            "param_value": "0",
            "default_value": "0",
            "value_type": "Integer",
            "value_range": "0-7200"
        },
        {
            "description": "Only events that run in more time than the configured latency-monitor-threshold will be logged as latency spikes. If latency-monitor-threshold is set to 0, latency monitoring is disabled. If latency-monitor-threshold is set to a value greater than 0, all events blocking the server for a time equal to or greater than the configured latency-monitor-threshold will be logged.",
            "param_id": 10,
            "param_name": "latency-monitor-threshold",
            "param_value": "0",
            "default_value": "0",
            "value_type": "Integer",
            "value_range": "0-86400000"
        },
        {
            "description": "The total memory, in bytes, reserved for non-data usage.",
            "param_id": 12,
            "param_name": "reserved-memory",
            "param_value": "0",
            "default_value": "0",
            "value_type": "Integer",
            "value_range": "0-6553"
        },
        {
            "description": "Redis can notify Pub or Sub clients about events happening in the key space",
            "param_id": 13,
            "param_name": "notify-keyspace-events",
            "param_value": null,
            "default_value": null,
            "value_type": "regular",
            "value_range": "([KE]+([A]|[g$lshzxe]+)){0,11}"
        }
    ],
    "config_status": "SUCCESS",
    "config_time": ""
}

Status Code

Table 11 describes the status code of successful operations. For details about other status codes, see Table 1.

Table 11 Status code

Status Code

Description

200

Instance configurations queried successfully.