Monitoring Features

Last updated: 2021-07-01 15:55:08

    TencentDB for Tendis provides a complete and easy-to-use monitoring service where you don’t have to worry about, for example, collecting monitoring data or OPS of the monitoring system. The monitoring service includes Proxy monitoring, Redis monitoring, and Tendis monitoring which summarizes the monitoring data of an entire instance. Details are as follows:

    • Proxy monitoring: provides monitoring information of all Proxy nodes in an instance. TencentDB for Tendis instances in standard or cluster architecture have Proxy nodes.
    • Redis monitoring: provides monitoring information of TencentDB for Tendis primary and secondary nodes.
    • Tendis monitoring: summarizes the monitoring data of an entire instance (including Proxy nodes and Tendis nodes) and aggregates data according to the SUM, AVG, MAX, and LAST aggregation algorithms.

    Monitoring Granularity and Monitoring Data Retention Period

    Tendis currently supports monitoring metrics at the 1-minute, 5-minutes, 1-hour, or 1-day granularity. For the retention period of monitoring data at each granularity, please see Use Limits.

    Viewing Monitoring Information

    You can view TencentDB for Tendis monitoring information in the instance list and on the instance monitoring page in the TencentDB for Tendis console, or in the Cloud Monitor console.

    • Instance list: log in to the TencentDB for Tendis console, click the View Monitoring icon in the instance list as shown below, and view monitoring metrics in the pop-up window on the right.
    • Instance monitoring page: log in to the TencentDB for Tendis console, click an instance ID in the instance list and enter the instance management page, select System Monitoring, and view monitoring data on the Monitoring Metrics tab.

    Monitoring Metric Description

    Proxy monitoring

    Each Tendis instance contains at least 3 Proxy nodes. Generally, the number of Proxy nodes is 1.5 times that of Tendis nodes. The Proxy node supports the following monitoring metrics:

    CategoryMetricParameterUnitDescription
    CPU CPU utilization cpu_util % Proxy CPU utilization
    Request Total requests proxy_commands requests/second The number of Proxy command executions per second
    Key requests cmd_key_count keys/second The number of keys accessed by a command per second
    Mget requests cmd_mget requests/second The number of Mget command executions per second
    Execution errors cmd_err errors/second The number of Proxy command execution errors per second, for example, when a command does not exist, parameters are incorrect, etc.
    Big value requests cmd_big_value requests/second The number of executions of commands larger than 32 KB per second
    Network Connections connections - The number of TCP connections to an instance
    Connection usage connections_util % The ratio of the number of TCP connections to the maximum number of connections
    Inbound traffic in_flow MB/s Private network inbound traffic
    Inbound traffic utilization in_bandwidth_util % The ratio of the actually used private inbound traffic to the maximum traffic
    Inbound traffic limit count in_flow_limit - The number of times inbound traffic triggers a traffic limit
    Outbound traffic out_flow MB/s Private network outbound traffic
    Outbound traffic utilization out_bandwidth_util % The ratio of the actually used private outbound traffic to the maximum traffic
    Outbound traffic limit count out_flow_limit - The number of times outbound traffic triggers a traffic limit
    Latency Average execution latency latency_avg ms The average execution latency from Proxy to Redis server
    Max execution latency latency_max ms The maximum execution latency from Proxy to Redis server
    Average read latency latency_read ms The average execution latency of read commands from Proxy to Redis server. For more information about read command types, please see Command types.
    Average write latency latency_write ms The average execution latency of write commands from Proxy to Redis server. For more information about write command types, please see Command types.
    Average latency of other commands latency_other ms The average execution latency of commands other than read and write commands from Proxy to Redis server

    Redis monitoring

    The Redis node monitoring includes monitoring information of all primary nodes and secondary nodes in an instance or a cluster. The following monitoring metrics are supported.

    CategoryMetricParameterUnitDescription
    CPU CPU utilization cpu_util % Average CPU utilization
    Network Connections connections - The number of connections from Proxy to a node
    Connection usage connections_util % The connection usage of a node
    Memory Used memory mem_used MB Memory capacity actually used, including data and cache
    Memory utilization mem_util % The ratio of the memory actually used to the total memory requested
    Keys keys - Total number of keys stored in an instance (first-level keys)
    Expired keys expired - The number of keys expired in a time window, which is equal to the value of `expired_keys` output by the `info` command
    Evicted keys evicted - The number of keys evicted in a time window, which is equal to the value of `evicted_keys` output by the `info` command
    Replication delay repl_delay Byte The command delay between the secondary node and the primary node
    Request Total requests commands queries/second QPS, that is, the number of command executions per second
    Read requests cmd_read requests/second The number of read command executions per second. For more information about read command types, please see Command types.
    Write requests cmd_write requests/second The number of write command executions per second. For more information about write command types, please see Command types.
    Other requests cmd_other requests/second The number of command (excluding write and read commands) executions per second
    Response Slow queries cmd_slow - The number of command executions with a latency greater than the `slowlog-log-slower-than` configuration
    Read request hits cmd_hits - The number of keys successfully requested by read commands, which is equal to the value of the `keyspace_hits` metric output by the `info` command
    Read request misses cmd_miss - The number of keys unsuccessfully requested by read commands, which is equal to the value of the `keyspace_misses` metric output by the `info` command
    Read request hit rate cmd_hits_ratio % Key hits/(Key hits + Key misses). This metric reflects the cache miss situation.

    Tendis monitoring

    The Tendis monitoring includes all monitoring data of an instance, including the monitoring data of Proxy nodes and Redis nodes, which is aggregated by the SUM, AVG, MAX, and LAST algorithms.

    CategoryMetricAssociated Node ViewParameterUnitDescription
    CPU CPU utilization Tendis node cpu_util % Average CPU utilization
    Max CPU utilization of a node Tendis node cpu_max_util % The maximum CPU utilization of a node (shard or replica) in an instance
    Memory Used memory Tendis node mem_used MB Memory capacity actually used, including data and cache
    Memory utilization Tendis node mem_util % The ratio of the memory actually used to the total memory requested
    Max memory utilization of a node Tendis node mem_max_util % The maximum memory utilization of a node (shard or replica) in an instance
    Keys Tendis node keys - Total number of keys stored in an instance (first-level keys)
    Expired keys Tendis node expired - The number of keys expired in a time window, which is equal to the value of `expired_keys` output by the `info` command
    Evicted keys Tendis node evicted - The number of keys evicted in a time window, which is equal to the value of `evicted_keys` output by the `info` command
    Network Connections Proxy node connections - The number of TCP connections to an instance
    Connection usage Proxy node connections_util % The ratio of the number of TCP connections to the maximum number of connections
    Inbound traffic Proxy node in_flow MB/s Private network inbound traffic
    Inbound traffic utilization Proxy node in_bandwidth_util % The ratio of the actually used private inbound traffic to the maximum traffic
    Inbound traffic limit count Proxy node in_flow_limit - The number of times inbound traffic triggers a traffic limit
    Outbound traffic Proxy node out_flow MB/s Private network outbound traffic
    Outbound traffic utilization Proxy node out_bandwidth_util % The ratio of the actually used private outbound traffic to the maximum traffic
    Outbound traffic limit count Proxy node out_flow_limit - The number of times outbound traffic triggers a traffic limit
    Average execution latency Proxy node latency_avg ms Average execution latency from Proxy to Redis server
    Max execution latency Proxy node latency_max ms Maximum execution latency from Proxy to Redis server
    Average read latency Proxy node latency_read ms The average execution latency of read commands from Proxy to Redis server. For more information about read command types, please see Command types.
    Average write latency Proxy node latency_write ms The average execution latency of write commands from Proxy to Redis server. For more information about wirte command types, please see Command types.
    Average latency of other commands Proxy node latency_other ms The average execution latency of commands other than read and write commands from Proxy to Redis server
    Request Total requests Tendis node commands requests/second QPS, that is, the number of command executions per second
    Read requests Tendis node cmd_read requests/second The number of read command executions per second. For more information about read command types, please see Command types.
    Write requests Tendis node cmd_write requests/second The number of write command executions per second. For more information about write command types, please see Command types.
    Other requests Tendis node cmd_other requests/second The number of command (excluding write and read commands) executions per second
    Big value requests Proxy node cmd_big_value requests/second The number of executions of commands larger than 32 KB per second
    Key requests Proxy node cmd_key_count keys/second The number of keys accessed by a command per second
    Mget requests Proxy node cmd_mget requests/second The number of Mget command executions per second
    Slow queries Tendis node cmd_slow - The number of command executions with a latency greater than the `slowlog-log-slower-than` configuration
    Read request hits Tendis node cmd_hits - The number of keys successfully requested by read commands, which is equal to the value of the `keyspace_hits` metric output by the `info` command
    Read request misses Tendis node cmd_miss - The number of keys unsuccessfully requested by read commands, which is equal to the value of the `keyspace_misses` metric output by the `info` command
    Execution errors Proxy node cmd_err - The number of command execution errors, for example, when a command does not exist, parameters are incorrect, etc.
    Read request hit rate Tendis node cmd_hits_ratio % Key hits/(Key hits + Key misses). This metric reflects the cache miss situation.

    Command types

    Type Commands
    Read command get, strlen, exists, getbit, getrange, substr, mget, llen, lindex, lrange, sismember, scard, srandmember,
    sinter, sunion, sdiff, smembers, sscan, zrange, zrangebyscore, zrevrangebyscore, zrangebylex,
    zrevrangebylex, zcount, zlexcount, zrevrange, zcard, zscore, zrank, zrevrank, zscan, hget, hmget,
    hlen, hstrlen, hkeys, hvals, hgetall, hexists, hscan, randomkey, keys, scan, dbsize, type, ttl, touch, pttl,
    dump, object, memory, bitcount, bitpos, georadius_ro, georadiusbymember_ro, geohash, geopos, geodist, pfcount
    Write command set, setnx, setex, psetex, append, del, unlink, setbit, bitfield, setrange, incr, decr, rpush, lpush, rpushx,
    lpushx, linsert, rpop, lpop, brpop, brpoplpush, blpop, lset, ltrim, lrem, rpoplpush, sadd, srem, smove, spop,
    sinterstore, sunionstore, sdiffstore, zadd, zincrby, zrem, zremrangebyscore, zremrangebyrank,
    zremrangebylex, zunionstore, zinterstore, hset, hsetnx, hmset, hincrby, hincrbyfloat, hdel, incrby, decrby,
    incrbyfloat, getset, mset, msetnx, swapdb, move, rename, renamenx, expire, expireat, pexpire, pexpireat,
    flushdb, flushall, sort, persist, restore, restore-asking, migrate, bitop, geoadd, georadius, georadiusbymember,
    pfadd, pfmerge, pfdebug