Querying DCS Instance 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.
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.

**Table 3** redis_config parameter description
Parameter	Type	Description
description	String	Configuration item description.
param_id	Integer	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.

Table 4 describes the configuration parameters of a DCS instance.

**Table 4** Configuration parameters of a DCS instance
Parameter ID	Parameter Name	Applicable Engine	Value Type	Description	Value Range	Default Value
1	timeout	Redis and Memcached	Interger	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 to 7200. Unit: second.	0
2	maxmemory-policy	Redis and Memcached	Enum	The policy applied when the maxmemory limit is reached. For details about parameter description, see What Is the Default Data Eviction Policy?	volatile-lru allkeys-lru volatile-random allkeys-random volatile-ttl noeviction volatile-lfu allkeys-lfu	volatile-lru NOTE: If the DCS Redis instance is created before July 2020 and this parameter has not been modified, the default value is noeviction. If the instance is created after July 2020, the default value is volatile-lru.
3	hash-max-ziplist-entries	Redis	Interger	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	Redis	Interger	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	Redis	Interger	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	Redis	Interger	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	Redis	Interger	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	Redis	Interger	When the number of entries in sorted sets is less than the value of this parameter, sorted sets are encoded using a ziplist to save memory.	1–10,000	128
9	zset-max-ziplist-value	Redis	Interger	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	Redis	Interger	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.	0–86,400,000 ms	0
12	reserved-memory	Redis	Interger	Reserved memory, which is available only for single-node and master/standby instances. This parameter indicates the number of megabytes reserved for the backend to perform internal processing such as persistence and master/standby replication. The size of the reserved memory can be adjusted, but must be in the value range described in the next column. NOTE: For more information about maximum available memory of each instance type, see DCS Service Overview.	0% to 80% of maximum memory space initially available to the instance and below the current free memory space. Unit: MB.	0
13	notify-keyspace-events	Redis	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 is an empty character string or null, the default value Ex is used. 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

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": "Enum",
            "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": "Interger",
            "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": "Interger",
            "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": "Interger",
            "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": "Interger",
            "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": "Interger",
            "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": "Interger",
            "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": "Interger",
            "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": "Interger",
            "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": "Interger",
            "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": "Interger",
            "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": ""
}