[[actuator]]
== Spring Boot Actuator


Spring Boot for {apache-geode-name} and {pivotal-gemfire-name} (SBDG) adds {spring-boot-docs-html}/production-ready.html[Spring Boot Actuator]
support and dedicated `HealthIndicators` for {apache-geode-name} and {pivotal-gemfire-name}.  Equally, the provided
`HealthIndicators` will even work with Pivotal Cloud Cache, which is backed by {pivotal-gemfire-name}, when pushing your
Spring Boot applications to Pivotal CloudFoundry (PCC).

Spring Boot `HealthIndicators` provide details about the runtime operation and behavior of your {apache-geode-name}
based Spring Boot applications.  For instance, by querying the right `HealthIndicator` endpoint, you would be able to
get the current hit/miss count for your `Region.get(key)` data access operations.

In addition to vital health information, SBDG provides basic, pre-runtime configuration meta-data about the
{apache-geode-name} components that are monitored by Spring Boot Actuator.  This makes it easier to see how
the application was configured all in one place, rather than in properties files, Spring config, XML, etc.

The provided Spring Boot `HealthIndicators` fall under one of three categories:

* Base `HealthIndicators` that apply to all {apache-geode-name}, Spring Boot applications, regardless of cache type,
such as Regions, Indexes and DiskStores.
* Peer `Cache` based `HealthIndicators` that are only applicable to peer `Cache` applications, such as
`AsyncEventQueues`, `CacheServers`, `GatewayReceivers` and `GatewaySenders`.
* And finally, `ClientCache` based `HealthIndicators` that are only applicable to `ClientCache` applications, such as
`ContinuousQueries` and connection `Pools`.

The following sections give a brief overview of all the available Spring Boot `HealthIndicators` provided for
{apache-geode-name} out-of-the-box.

TIP: Refer to the corresponding Sample link:guides/boot-actuator.html[Guide] and {github-samples-url}/boot/actuator[Code]
to see the Spring Boot Actuator for {apache-geode-name} in action!

[[actuator-base-healthindicators]]
=== Base `HealthIndicators`

The following section covers Spring Boot `HealthIndicators` that apply to both peer `Cache` and `ClientCache`,
Spring Boot applications.  That is, these `HealthIndicators` are not specific to the cache type.

In {apache-geode-name}, the cache instance is either a peer `Cache` instance, which makes your Spring Boot application
part of a {apache-geode-name} cluster, or more commonly, a `ClientCache` instance that talks to an existing cluster.
Your Spring Boot application can only be one cache type or the other and can only have a single instance of
that cache type.

[[actuator-base-healthindicators-cache]]
==== GeodeCacheHealthIndicator

The `GeodeCacheHealthIndicator` provides essential details about the (single) cache instance (Client or Peer) along with
the underlying `DistributedSystem`, the `DistributedMember` and configuration details of the `ResourceManager`.

When your Spring Boot application creates an instance of a peer {apache-geode-javadoc}/org/apache/geode/cache/Cache.html[`Cache`],
the {apache-geode-javadoc}/org/apache/geode/distributed/DistributedMember.html[`DistributedMember`] object represents
your application as a peer member/node of the {apache-geode-javadoc}/org/apache/geode/distributed/DistributedSystem.html[`DistributedSystem`]
formed from a collection of connected peers (i.e. the cluster), to which your application also has
{apache-geode-javadoc}/org/apache/geode/cache/GemFireCache.html#getDistributedSystem--[access],
indirectly via the cache instance.

This is no different for a `ClientCache` even though the client is technically not part of the peer/server cluster.
But, it still creates instances of the `DistributedSystem` and `DistributedMember` objects, respectively.

The following configuration meta-data and health details about each object is covered:

.Cache Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                           | Description

| geode.cache.name               | Name of the member in the distributed system.
| geode.cache.closed             | Determines whether the cache has been closed.
| geode.cache.cancel-in-progress | Cancellation of operations in progress.

|=====================================================================================================================

.DistributedMember Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                 | Description

| geode.distributed-member.id          | DistributedMember identifier (used in logs internally).
| geode.distributed-member.name        | Name of the member in the distributed system.
| geode.distributed-members.groups     | Configured groups to which the member belongs.
| geode.distributed-members.host       | Name of the machine on which the member is running.
| geode.distributed-members.process-id | Identifier of the JVM process (PID).

|=====================================================================================================================

.DistributedSystem Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                  | Description

| geode.distributed-system.member-count                 | Total number of members in the cluster (1 for clients).
| geode.distributed-system.connected                    | Indicates whether the member is currently connected to
the cluster.
| geode.distributed-system.reconnecting                 | Indicates whether the member is in a reconnecting state,
which happens when a network partition occurs and the member gets disconnected from the cluster.
| geode.distributed-system.properties-location          | Location of the
{apache-geode-docs}/topics/gemfire_properties.html[standard configuration properties].
| geode.distributed-system.security-properties-location | Location of the
{apache-geode-docs}/topics/gemfire_properties.html[security configuration properties].

|=====================================================================================================================

.ResourceManager Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                | Description

| geode.resource-manager.critical-heap-percentage     | Percentage of heap at which the cache is in danger of
becoming inoperable.
| geode.resource-manager.critical-off-heap-percentage | Percentage of off-heap at which the cache is in danger of
becoming inoperable.
| geode.resource-manager.eviction-heap-percentage     | Percentage of heap at which eviction begins on Regions
configured with a Heap LRU Eviction policy.
| geode.resource-manager.eviction-off-heap-percentage | Percentage of off-heap at which eviction begins on Regions
configured with a Heap LRU Eviction policy.

|=====================================================================================================================


[[actuator-base-healthindicators-regions]]
==== GeodeRegionsHealthIndicator

The `GeodeRegionsHealthIndicator` provides details about all the configured and known `Regions` in the cache.
If the cache is a client, then details will include all LOCAL, PROXY and CACHING_PROXY `Regions`. If the cache
is a peer, then the details will include all LOCAL, PARTITION and REPLICATE `Regions`.

While the configuration meta-data details are not exhaustive, essential details along with basic performance metrics
are covered:

.Region Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                        | Description

| geode.cache.regions.<name>.cloning-enabled  | Whether Region values are cloned on read (e.g. `cloning-enabled`
is `true` when cache transactions are used to prevent in-place modifications).
| geode.cache.regions.<name>.data-policy      | Policy used to manage the data in the Region
(e.g. PARTITION, REPLICATE, etc).
| geode.cache.regions.<name>.initial-capacity | Initial number of entries that can be held by a Region before
it needs to be resized.
| geode.cache.regions.<name>.load-factor      | Load factor used to determine when to resize the Region
when it nears capacity.
| geode.cache.regions.<name>.key-constraint   | Type constraint for Region keys.
| geode.cache.regions.<name>.off-heap         | Determines whether this Region will store values in off-heap memory
(NOTE: Keys are always kept on Heap).
| geode.cache.regions.<name>.pool-name        | If this Region is a client Region, then this property determines
the configured connection `Pool` (NOTE: Regions can have and use dedicated `Pools` for their data access operations.)
| geode.cache.regions.<name>.pool-name        | Determines the `Scope` of the Region, which plays a factor in
the Regions consistency-level, as it pertains to acknowledgements for writes.
| geode.cache.regions.<name>.value-constraint | Type constraint for Region values.

|=====================================================================================================================

Additionally, when the Region is a peer `Cache` `PARTITION` Region, then the following details are also covered:

.Partition Region Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                         | Description

| geode.cache.regions.<name>.partition.collocated-with         | Indicates this Region is collocated with another
PARTITION Region, which is necessary when performing equi-joins queries (NOTE: distributed joins are not supported).
| geode.cache.regions.<name>.partition.local-max-memory        | Total amount of Heap memory allowed to be used by
this Region on this node.
| geode.cache.regions.<name>.partition.redundant-copies        | Number of replicas for this PARTITION Region,
which is useful in High Availability (HA) use cases.
| geode.cache.regions.<name>.partition.total-max-memory        | Total amount of Heap memory allowed to be used by
this Region across all nodes in the cluster hosting this Region.
| geode.cache.regions.<name>.partition.total-number-of-buckets | Total number of buckets (shards) that this Region
is divided up into (NOTE: defaults to 113).

|=====================================================================================================================

Finally, when statistics are enabled (e.g. using `@EnableStatistics`,
(see {spring-data-geode-docs-html}/#bootstrap-annotation-config-statistics[here]
for more details), the following details are available:

.Region Statistic Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                     | Description

| geode.cache.regions.<name>.statistics.hit-count          | Number of hits for a Region entry.
| geode.cache.regions.<name>.statistics.hit-ratio          | Ratio of hits to the number of `Region.get(key)` calls.
| geode.cache.regions.<name>.statistics.last-accessed-time | For an entry, determines the last time it was accessed
with `Region.get(key)`.
| geode.cache.regions.<name>.statistics.last-modified-time | For an entry, determines the time a Region's entry value
was last modified.
| geode.cache.regions.<name>.statistics.miss-count         | Returns the number of times that a `Region.get`
was performed and no value was found locally.

|=====================================================================================================================


[[actuator-base-healthindicators-indexes]]
==== GeodeIndexesHealthIndicator

The `GeodeIndexesHealthIndicator` provides details about the configured Region `Indexes` used in OQL query
data access operations.

The following details are covered:

.Index Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                     | Description

| geode.index.<name>.from-clause           | Region from which data is selected.
| geode.index.<name>.indexed-expression    | The Region value fields/properties used in the Index expression.
| geode.index.<name>.projection-attributes | For all other Indexes, returns "*", but for Map Indexes, returns either "*"
or the specific Map keys that were indexed.
| geode.index.<name>.region                | Region to which the Index is applied.

|=====================================================================================================================

Additionally, when statistics are enabled (e.g. using `@EnableStatistics`;
(see {spring-data-geode-docs-html}/#bootstrap-annotation-config-statistics[here]
for more details), the following details are available:

.Index Statistic Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                     | Description

| geode.index.<name>.statistics.number-of-bucket-indexes   | Number of bucket Indexes created in a Partitioned Region.
| geode.index.<name>.statistics.number-of-keys             | Number of keys in this Index.
| geode.index.<name>.statistics.number-of-map-indexed-keys | Number of keys in this Index at the highest-level.
| geode.index.<name>.statistics.number-of-values           | Number of values in this Index.
| geode.index.<name>.statistics.number-of-updates          | Number of times this Index has been updated.
| geode.index.<name>.statistics.read-lock-count            | Number of read locks taken on this Index.
| geode.index.<name>.statistics.total-update-time          | Total amount of time (ns) spent updating
this Index.
| geode.index.<name>.statistics.total-uses                 | Total number of times this Index has been accessed by
an OQL query.

|=====================================================================================================================

[[actuator-base-healthindicators-diskstores]]
==== GeodeDiskStoresHealthIndicator

The `GeodeDiskStoresHealthIndicator` provides details about the configured `DiskStores` in the system/application.
Remember, `DiskStores` are used to overflow and persist data to disk, including type meta-data tracked by PDX
when the values in the Region(s) have been serialized with PDX and the Region(s) are persistent.

Most of the tracked health information pertains to configuration:

.DiskStore Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                            | Description

| geode.disk-store.<name>.allow-force-compaction         | Indicates whether manual compaction of the DiskStore
is allowed.
| geode.disk-store.<name>.auto-compact                   | Indicates if compaction occurs automatically.
| geode.disk-store.<name>.compaction-threshold           | Percentage at which the oplog will become compactable.
| geode.disk-store.<name>.disk-directories               | Location of the oplog disk files.
| geode.disk-store.<name>.disk-directory-sizes           | Configured and allowed sizes (MB) for the disk directory
storing the disk files.
| geode.disk-store.<name>.disk-usage-critical-percentage | Critical threshold of disk usage proportional to
the total disk volume.
| geode.disk-store.<name>.disk-usage-warning-percentage  | Warning threshold of disk usage proportional to
the total disk volume.
| geode.disk-store.<name>.max-oplog-size                 | Maximum size (MB) allowed for a single oplog file.
| geode.disk-store.<name>.queue-size                     | Size of the queue used to batch writes flushed to disk.
| geode.disk-store.<name>.time-interval                  | Time to wait (ms) before writes are flushed to disk
from the queue if the size limit has not be reached.
| geode.disk-store.<name>.uuid                           | Universally Unique Identifier for the DiskStore across
Distributed System.
| geode.disk-store.<name>.write-buffer-size              | Size the of write buffer the DiskStore uses to write data
to disk.

|=====================================================================================================================

[[actuator-clientcache-healthindicators]]
=== `ClientCache` `HealthIndicators`

The `ClientCache` based `HealthIndicators` provide additional details specifically for Spring Boot, cache client
applications.  These `HealthIndicators` are only available when the Spring Boot application creates a `ClientCache`
instance (i.e. is a cache client), which is the default.

[[actuator-clientcache-healthindicators-cq]]
==== GeodeContinuousQueriesHealthIndicator

The `GeodeContinuousQueriesHealthIndicator` provides details about registered client Continuous Queries (CQ).
CQs enable client applications to receive automatic notification about events that satisfy some criteria. That criteria
can be easily expressed using the predicate of an OQL query (e.g. "`SELECT * FROM /Customers c WHERE c.age > 21`").
Anytime data of interests is inserted or updated, and matches the criteria specified in the OQL query predicate,
an event is sent to the registered client.

The following details are covered for CQs by name:

.Continuous Query(CQ) Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                            | Description

| geode.continuous-query.<name>.oql-query-string  | OQL query constituting the CQ.
| geode.continuous-query.<name>.closed            | Indicates whether the CQ has been closed.
| geode.continuous-query.<name>.closing           | Indicates whether the CQ is the process of closing.
| geode.continuous-query.<name>.durable           | Indicates whether the CQ events will be remembered
between client sessions.
| geode.continuous-query.<name>.running           | Indicates whether the CQ is currently running.
| geode.continuous-query.<name>.stopped           | Indicates whether the CQ has been stopped.

|=====================================================================================================================

In addition, the following CQ query and statistical data is covered:

.Continuous Query(CQ), Query Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                       | Description

| geode.continuous-query.<name>.query.number-of-executions   | Total number of times the query has been executed.
| geode.continuous-query.<name>.query.total-execution-time   | Total amount of time (ns) spent executing the query.
| geode.continuous-query.<name>.statistics.number-of-deletes |

|=====================================================================================================================


.Continuous Query(CQ), Statistic Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                       | Description

| geode.continuous-query.<name>.statistics.number-of-deletes | Number of Delete events qualified by this CQ.
| geode.continuous-query.<name>.statistics.number-of-events  | Total number of events qualified by this CQ.
| geode.continuous-query.<name>.statistics.number-of-inserts | Number of Insert events qualified by this CQ.
| geode.continuous-query.<name>.statistics.number-of-updates | Number of Update events qualified by this CQ.

|=====================================================================================================================

In a more general sense, the {apache-geode-name} Continuous Query system is tracked with the following,
additional details on the client:

.Continuous Query(CQ), Statistic Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                       | Description

| geode.continuous-query.count                               | Total count of CQs.
| geode.continuous-query.number-of-active                    | Number of currently active CQs (if available).
| geode.continuous-query.number-of-closed                    | Total number of closed CQs (if available).
| geode.continuous-query.number-of-created                   | Total number of created CQs (if available).
| geode.continuous-query.number-of-stopped                   | Number of currently stopped CQs (if available).
| geode.continuous-query.number-on-client                    | Number of CQs that are currently active or stopped
(if available).

|=====================================================================================================================

[[actuator-clientcache-healthindicators-pools]]
==== GeodePoolsHealthIndicator

The `GeodePoolsHealthIndicator` provide details about all the configured client connection `Pools`.
This `HealthIndicator` primarily provides configuration meta-data for all the configured `Pools`.

The following details are covered:

.Pool Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                    | Description

| geode.pool.count                                        | Total number of client connection Pools.
| geode.pool.<name>.destroyed                             | Indicates whether the Pool has been destroyed.
| geode.pool.<name>.free-connection-timeout               | Configured amount of time to wait for a free connection
from the Pool.
| geode.pool.<name>.idle-timeout                          | The amount of time to wait before closing unused,
idle connections not exceeding the configured number of minimum required connections.
| geode.pool.<name>.load-conditioning-interval            | Controls how frequently the Pool will check to see
if a connection to a given server should be moved to a different server to improve the load balance.
| geode.pool.<name>.locators                              | List of configured Locators.
| geode.pool.<name>.max-connections                       | Maximum number of connections obtainable from the Pool.
| geode.pool.<name>.min-connections                       | Minimum number of connections contained by the Pool.
| geode.pool.<name>.multi-user-authentication             | Determines whether the Pool can be used by
multiple authenticated users.
| geode.pool.<name>.online-locators                       | Returns a list of living Locators.
| geode.pool.<name>.pending-event-count                   | Approximate number of pending subscription events
maintained at server for this durable client Pool at the time it (re)connected to the server.
| geode.pool.<name>.ping-interval                         | How often to ping the servers to verify they are still alive.
| geode.pool.<name>.pr-single-hop-enabled                 | Whether the client will acquire a direct connection to
the server containing the data of interests.
| geode.pool.<name>.read-timeout                          | Number of milliseconds to wait for a response from a server
before timing out the operation and trying another server (if any are available).
| geode.pool.<name>.retry-attempts                        | Number of times to retry a request after timeout/exception.
| geode.pool.<name>.server-group                          | Configures the group in which all servers this Pool
connects to must belong.
| geode.pool.<name>.servers                               | List of configured servers.
| geode.pool.<name>.socket-buffer-size                    | Socket buffer size for each connection made in this Pool.
| geode.pool.<name>.statistic-interval                    | How often to send client statistics to the server.
| geode.pool.<name>.subscription-ack-interval             | Interval in milliseconds to wait before sending
acknowledgements to the cache server for events received from the server subscriptions.
| geode.pool.<name>.subscription-enabled                  | Enabled server-to-client subscriptions.
| geode.pool.<name>.subscription-message-tracking-timeout | Time-to-Live period (ms), for subscription events
the client has received from the server.
| geode.pool.<name>.subscription-redundancy               | Redundancy level for this Pools server-to-client
subscriptions, which is used to ensure clients will not miss potentially important events.
| geode.pool.<name>.thread-local-connections              | Thread local connection policy for this Pool.

|=====================================================================================================================


[[actuator-peercache-healthindicators]]
=== Peer `Cache` `HealthIndicators`

The peer `Cache` based `HealthIndicators` provide additional details specifically for Spring Boot, peer cache member
applications.  These `HealthIndicators` are only available when the Spring Boot application creates a peer `Cache`
instance.

NOTE: The default cache instance created by Spring Boot for {apache-geode-name} is a `ClientCache` instance.

TIP: To control what type of cache instance is created, such as a "peer", then you can explicitly declare either the
`@PeerCacheApplication`, or alternatively, the `@CacheServerApplication`, annotation on your `@SpringBootApplication`
annotated class.

[[actuator-peercache-healthindicators-cacheservers]]
==== GeodeCacheServersHealthIndicator

The `GeodeCacheServersHealthIndicator` provides details about the configured {apache-geode-name} `CacheServers`.
`CacheServer` instances are required to enable clients to connect to the servers in the cluster.

This `HealthIndicator` captures basic configuration meta-data and runtime behavior/characteristics of
the configured `CacheServers`:

.CacheServer Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                               | Description

| geode.cache.server.count                           | Total number of configured CacheServer instances
on this peer member.
| geode.cache.server.<index>.bind-address            | IP address of the NIC to which the CacheServer `ServerSocket`
is bound (useful when the system contains multiple NICs).
| geode.cache.server.<index>.hostname-for-clients    | Name of the host used by clients to connect to the CacheServer
(useful with DNS).
| geode.cache.server.<index>.load-poll-interval      | How often (ms) to query the load probe on the CacheServer.
| geode.cache.server.<index>.max-connections         | Maximum number of connections allowed to this CacheServer.
| geode.cache.server.<index>.max-message-count       | Maximum number of messages that can be enqueued in
a client queue.
| geode.cache.server.<index>.max-threads             | Maximum number of Threads allowed in this CacheServer
to service client requests.
| geode.cache.server.<index>.max-time-between-pings  | Maximum time between client pings.
| geode.cache.server.<index>.message-time-to-live    | Time (seconds) in which the client queue will expire.
| geode.cache.server.<index>.port                    | Network port to which the CacheServer `ServerSocket` is bound
and listening for the client connections.
| geode.cache.server.<index>.running                 | Determines whether this CacheServer is currently running
and accepting client connections.
| geode.cache.server.<index>.socket-buffer-size      | Configured buffer size of the Socket connection
used by this CacheServer.
| geode.cache.server.<index>.tcp-no-delay            | Configures the TCP/IP TCP_NO_DELAY setting on outgoing Sockets.

|=====================================================================================================================

In addition to the configuration settings shown above, the `CacheServer's` `ServerLoadProbe` tracks additional details
about the runtime characteristics of the `CacheServer`, as follows:

.CacheServer Metrics and Load Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                             | Description

| geode.cache.server.<index>.load.connection-load                  | Load on the server due to client to server
connections.
| geode.cache.server.<index>.load.load-per-connection              | Estimate of the how much load each new connection
will add to this server.
| geode.cache.server.<index>.load.subscription-connection-load     | Load on the server due to subscription connections.
| geode.cache.server.<index>.load.load-per-subscription-connection | Estimate of the how much load each new subscriber
will add to this server.
| geode.cache.server.<index>.metrics.client-count                  | Number of connected clients.
| geode.cache.server.<index>.metrics.max-connection-count          | Maximum number of connections made to this
CacheServer.
| geode.cache.server.<index>.metrics.open-connection-count         | Number of open connections to this CacheServer.
| geode.cache.server.<index>.metrics.subscription-connection-count | Number of subscription connections to this
CacheServer.

|=====================================================================================================================

[[actuator-peercache-healthindicators-aeq]]
==== GeodeAsyncEventQueuesHealthIndicator

The `GeodeAsyncEventQueuesHealthIndicator` provides details about the configured `AsyncEventQueues`.  AEQs can be
attached to Regions to configure asynchronous, write-behind behavior.

This `HealthIndicator` captures  configuration meta-data and runtime characteristics for all AEQs, as follows:

.AsyncEventQueue Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                    | Description

| geode.async-event-queue.count                           | Total number of configured AEQs.
| geode.async-event-queue.<id>.batch-conflation-enabled   | Indicates whether batch events are conflated when sent.
| geode.async-event-queue.<id>.batch-size                 | Size of the batch that gets delivered over this AEQ.
| geode.async-event-queue.<id>.batch-time-interval        | Max time interval that can elapse before a batch is sent.
| geode.async-event-queue.<id>.disk-store-name            | Name of the disk store used to overflow & persist events.
| geode.async-event-queue.<id>.disk-synchronous           | Indicates whether disk writes are sync or async.
| geode.async-event-queue.<id>.dispatcher-threads         | Number of Threads used to dispatch events.
| geode.async-event-queue.<id>.forward-expiration-destroy | Indicates whether expiration destroy operations
are forwarded to AsyncEventListener.
| geode.async-event-queue.<id>.max-queue-memory           | Maximum memory used before data needs to be overflowed
to disk.
| geode.async-event-queue.<id>.order-policy               | Order policy followed while dispatching the events to
AsyncEventListeners.
| geode.async-event-queue.<id>.parallel                   | Indicates whether this queue is parallel (higher throughput)
or serial.
| geode.async-event-queue.<id>.persistent                 | Indicates whether this queue stores events to disk.
| geode.async-event-queue.<id>.primary                    | Indicates whether this queue is primary or secondary.
| geode.async-event-queue.<id>.size                       | Number of entries in this queue.

|=====================================================================================================================


[[actuator-peercache-healthindicators-gateway-receivers]]
==== GeodeGatewayReceiversHealthIndicator

The `GeodeGatewayReceiversHealthIndicator` provide details about the configured (WAN) `GatewayReceivers`, which are
capable of receiving events from remote clusters when using {apache-geode-name}'s
{apache-geode-docs}/topologies_and_comm/multi_site_configuration/chapter_overview.html[multi-site, WAN topology].

This `HealthIndicator` captures configuration meta-data along with the running state for each `GatewayReceiver`:

.GatewayReceiver Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                    | Description

| geode.gateway-receiver.count                            | Total number of configured GatewayReceivers.
| geode.gateway-receiver.<index>.bind-address             | IP address of the NIC to which the GatewayReceiver
`ServerSocket` is bound (useful when the system contains multiple NICs).
| geode.gateway-receiver.<index>.end-port                 | End value of the port range from which the GatewayReceiver's
port will be chosen.
| geode.gateway-receiver.<index>.host                     | IP address or hostname that Locators will tell clients
(i.e. GatewaySenders) that this GatewayReceiver is listening on.
| geode.gateway-receiver.<index>.max-time-between-pings   | Maximum amount of time between client pings.
| geode.gateway-receiver.<index>.port                     | Port on which this GatewayReceiver listens for clients
(i.e. GatewaySenders).
| geode.gateway-receiver.<index>.running                  | Indicates whether this GatewayReceiver is running
and accepting client connections (from GatewaySenders).
| geode.gateway-receiver.<index>.socket-buffer-size       | Configured buffer size for the Socket connections used by
this GatewayReceiver.
| geode.gateway-receiver.<index>.start-port               | Start value of the port range from which the
GatewayReceiver's  port will be chosen.

|=====================================================================================================================

[[actuator-peercache-healthindicators-gateway-senders]]
==== GeodeGatewaySendersHealthIndicator

The `GeodeGatewaySendersHealthIndicator` provides details about the configured `GatewaySenders`.  `GatewaySenders` are
attached to Regions in order to send Region events to remote clusters in {apache-geode-name}'s
 {apache-geode-docs}/topologies_and_comm/multi_site_configuration/chapter_overview.html[multi-site, WAN topology].

This `HealthIndicator` captures essential configuration meta-data and runtime characteristics for each `GatewaySender`:

.GatewaySender Details
[width="90%",cols="^3,<10",options="header"]
|=====================================================================================================================
| Name                                                    | Description

| geode.gateway-sender.count                                      | Total number of configured GatewaySenders.
| geode.gateway-sender.<id>.alert-threshold                       | Alert threshold (ms) for entries in this
GatewaySender's queue.
| geode.gateway-sender.<id>.batch-conflation-enabled              | Indicates whether batch events are conflated
when sent.
| geode.gateway-sender.<id>.batch-size                            | Size of the batches sent.
| geode.gateway-sender.<id>.batch-time-interval                   | Max time interval that can elapse before a batch
is sent.
| geode.gateway-sender.<id>.disk-store-name                       | Name of the DiskStore used to overflow and persist
queue events.
| geode.gateway-sender.<id>.disk-synchronous                      | Indicates whether disk writes are sync or async.
| geode.gateway-sender.<id>.dispatcher-threads                    | Number of Threads used to dispatch events.
| geode.gateway-sender.<id>.max-queue-memory                      | Maximum amount of memory (MB) usable for this
GatewaySender's queue.
| geode.gateway-sender.<id>.max-parallelism-for-replicated-region |
| geode.gateway-sender.<id>.order-policy                          | Order policy followed while dispatching the events
to GatewayReceivers.
| geode.gateway-sender.<id>.parallel                              | Indicates whether this GatewaySender is parallel
(higher throughput) or serial.
| geode.gateway-sender.<id>.paused                                | Indicates whether this GatewaySender is paused.
| geode.gateway-sender.<id>.persistent                            | Indicates whether this GatewaySender persists queue
events to disk.
| geode.gateway-sender.<id>.remote-distributed-system-id          | Identifier for the remote distributed system.
| geode.gateway-sender.<id>.running                               | Indicates whether this GatewaySender
is currently running.
| geode.gateway-sender.<id>.socket-buffer-size                    | Configured buffer size for the Socket connections
between this GatewaySender and its receiving GatewayReceiver.
| geode.gateway-sender.<id>.socket-read-timeout                   | Amount of time (ms) that a Socket read between
this sending GatewaySender and its receiving GatewayReceiver will block.

|=====================================================================================================================
