ApsaraDB for Redis monitors more than 10 groups of metrics in real time. This allows you to monitor the status of ApsaraDB for Redis instances. This topic describes the purpose of each metric.

Monitoring frequency and monitoring cycle

The frequency that the performance monitoring system collects monitoring data is the monitoring frequency. If the system collects data every 5 seconds, the monitoring frequency is once every 5 seconds, and the monitoring cycle (or collection cycle) is 5 seconds. For more information about how to modify the monitoring frequency, see Modify the monitoring frequency.

Note The default monitoring frequency is once every 60 seconds.

Aggregated metrics

By default, the aggregated metrics of read/write splitting or cluster instances are displayed on the Performance Monitor page. You can also click Data Node or Proxy to view the metrics in different monitoring groups of each node. For more information, see Custom monitoring groups and custom metrics.

Note ApsaraDB for Redis will support more monitoring metrics in the future.
Metric Unit Description
CpuUsage % The average CPU usage of all data nodes.
UsedMemory Bytes The total memory used by all data nodes. This includes the memory consumed by the data and cache.
Keys Counts The total number of keys on all data nodes.
Expires Counts The total number of keys for which the expiration time is set.
ExpiredKeys Counts The total number of expired keys on all data nodes.
EvictedKeys Counts The total number of keys that are evicted on all data nodes.
HitRate % The average hit ratio of keys for all data nodes. Hit ratio = (Total key hits)/(Total key hits + Total key misses).

Custom monitoring groups and custom metrics

You can view metrics in each monitoring group for data nodes or proxy nodes. For more information, see Customize metrics. The following table lists the monitoring groups.

Monitoring group Description
Basic Monitoring Group The basic monitoring metrics of an instance, such as queries per second (QPS), bandwidth, and memory usage. For more information, see Table 1.
Key Monitoring Group The metrics on the use of key-value related commands, such as the number of times DEL and EXITS are run.
String Monitoring Group The metrics on the use of string-related commands, such as the number of times APPEND and MGET are run.
Hash Monitoring Group The metrics on the use of hash-related commands, such as the number of times HGET and HDEL are run.
List Monitoring Group The metrics on the use of list-related commands, such as the number of times BLPOP and BRPOP are run.
Set Monitoring Group The metrics on the use of set-related commands, such as the number of times SADD and SCARD are run.
Zset Monitoring Group The metrics on the use of zset-related commands, such as the number of times ZADD and ZCARD are run.
HyperLog Monitoring Group The metrics on the use of HyperLogLog-related commands, such as the number of times PFADD and PFCOUNT are run.
Pub/Sub Monitoring Group The metrics on the use of publication and subscription-related commands, such as the number of times PUBLISH and SUBSCRIBE are run.
Transaction Monitoring Group The metrics on the use of transaction-related commands, such as the number of times WATCH, MULTI, and EXEC are run.
Lua Script Monitoring Group The metrics on the use of Lua script-related commands, such as the number of times EVAL and SCRIPT are run.
TairDoc monitoring group (for Enhanced Edition only) The metrics on the use of TairDoc commands, such as the number of times JSON.SET and JSON.GET are run.
TairHash monitoring group (for Enhanced Edition only) The metrics on the use of TairHash commands, such as the number of times EXHSET and EXHMSET are run.
TairString monitoring group (for Enhanced Edition only) The metrics on the use of TairString commands, such as the number of times EXSET and EXGET are run.
TairGis monitoring group (for Enhanced Edition only) The metrics on the use of TairGis commands, such as the number of times GIS.ADD, GIS.GET, and GIS.DEL are run.
TairBloom monitoring group (for Enhanced Edition only) The metrics on the use of TairBloom commands, such as the number of times BF.RESERVE and BF.ADD are run.

The preceding monitoring groups can be classified into Basic Monitoring Group and other monitoring groups.

  • Metrics in the basic monitoring group
    Table 1. Metrics in the basic monitoring group
    Type Metric Unit Description
    CPU CpuUsage % The CPU usage.
    Memory UsedMemory Bytes The amount of used memory, which includes the memory consumed by the data and cache.
    MemoryUsage % The memory usage.
    Note Redis 2.8 instances are not supported. To display this metric, you must upgrade the engine version of the instance. For more information, see Upgrade the major version.
    Keys Counts The total number of keys.
    ExpiredKeysPerSecond Counts/s The number of expired keys per second.
    EvictedKeysPerSecond Counts/s The number of evicted keys per second.
    Disk (only for hybrid-storage instances) DataSize MB The size of data files.
    LogSize MB The size of logs.
    Request TotalQps Counts/s The total number of requests per second, which includes read and write requests.
    GetQps Counts/s The number of read requests per second.
    Note The engine version of the ApsaraDB for Redis instance must be Redis 4.0 or later with the latest minor version. For more information, see Upgrade the major version and Upgrade the minor version.
    PutQps Counts/s The number of write requests per second.
    Note The engine version of the ApsaraDB for Redis instance must be Redis 4.0 or later with the latest minor version. For more information, see Upgrade the major version and Upgrade the minor version.
    Network UsedConnection Counts The number of used connections. This is also the number of Transmission Control Protocol (TCP) connections to the instance.
    Note If you use a cluster instance and connect to the instance by using the proxy endpoint, you need to pay attention to the number of connections on each proxy node.
    ConnectionUsage % The connections usage. Connections usage = Number of connections/Total number of connections supported by the instance.
    IntranetIn KBps The inbound traffic of the instance.
    IntranetInRatio % The usage rate of the inbound traffic.
    IntranetOut KBps The outbound traffic of the instance.
    IntranetOutRatio % The usage rate of the outbound traffic.
    Latency AvgRt us The average response time that is consumed by all commands. This is the average time period from the time when the data node receives the command to the time when the data node returns the result.
    MaxRt us The maximum response time of requests. This is the maximum response time at which a data node sends a response after it receives a command.
    Response hit Counts The number of keys that are hit per second.
    miss Counts The number of keys that are missed per second.
    HitRate % The hit ratio of keys. Hit ratio = (Total key hits)/(Total key hits + Total key misses).
  • Other monitoring metrics

    You can also click Customize Metrics to view metrics of other monitoring groups. These metrics show the number of times the related commands are run. To understand what information a metric provides, you only need to identify the metric category based on the metric name.

    For example, the del, dump, and exists metrics in the Key Monitoring Group specify the number of times the DEL, DUMP, and EXISTS commands are run.

    Key monitoring group