Resource Usage - Redis

The following metrics are available in the Redis Software Cluster Manager UI.

Connections

Number of connections to the database.

Components measured: Cluster, Node, and Database

CPU usage

Percent of the node CPU used.

Components measured: Cluster and Node

Main thread CPU usage

Percent of the CPU used by the main thread.

Components measured: Database and Shard

Fork CPU usage

CPU usage of Redis child forks.

Components measured: Database and Shard

Total CPU usage

Percent usage of the CPU for all nodes.

Components measured: Database

Free disk space

Remaining unused disk space.

Components measured: Cluster and Node

Memory

Used memory

Total memory used by the database, including RAM, [Flash]({{< relref "/operate/rs/databases/flash" >}}) (if enabled), and [replication]({{< relref "/operate/rs/databases/durability-ha/replication" >}}) (if enabled).

Used memory does not include:

Fragmentation overhead - The ratio of memory seen by the operating system to memory allocated by Redis
Replication buffers at the primary nodes - Set to 10% of used memory and is between 64 MB and 2048 MB
Memory used by Lua scripts - Does not exceed 1 MB
Copy on Write (COW) operation that can be triggered by:
- A full replication process
- A database snapshot process
- AOF rewrite process

Used memory is not measured during [shard migration]({{< relref "/operate/rs/databases/configure/replica-ha" >}}).

Additional factors for [Active-Active databases]({{<relref "/operate/rs/databases/active-active">}}):

By default, the [Active-Active replication backlog]({{<relref "/operate/rs/databases/active-active/manage#replication-backlog">}}), used for synchronization between clusters or regions, is set to 1% of the database size.
Active-Active databases have a lower threshold for activating the eviction policy, because it requires propagation to all participating clusters. The eviction policy starts to evict keys when one of the Active-Active instances reaches 80% of its memory limit.

Components measured: Database and Shard

Free RAM

Available RAM for System use.

Components measured: Cluster and Node

Memory limit

Memory size limit of the database, enforced on the used memory.

Components measured: Database

Memory usage

Percent of memory used by Redis out of the memory limit.

Components measured: Database

Traffic

Incoming traffic

Total incoming traffic to the database in bytes/sec.

All incoming traffic is not measured during [shard migration]({{< relref "/operate/rs/databases/configure/replica-ha" >}}).

Components measured: Cluster, Node and Database

Incoming traffic compressed

Total incoming compressed traffic (in bytes/sec) per [Active-Active]({{< relref "/operate/rs/databases/active-active" >}}) replica database.

Incoming traffic uncompressed

Total incoming uncompressed traffic (in bytes/sec) per [Active-Active]({{< relref "/operate/rs/databases/active-active" >}}) replica database.

Outgoing traffic

Total outgoing traffic from the database in bytes per second.

Outgoing traffic is not measured during [shard migration]({{< relref "/operate/rs/databases/configure/replica-ha" >}}).

Components measured: Cluster, Node and Database