Metrics API reference

The Jenkins Metrics plugin from the open source community defines an API for integrating the Dropwizard Metrics API, defines a number of standard metrics, and provides some basic health checks.

Authentication

To access the Metrics API you need an API authentication token. See API authentication for more information.

Authorization

Authenticated users can access the Dropwizard Metrics Servlet at $JENKINS_URL/metrics/currentUser/ if they have the Metrics/View permission.

Access to the thread dumps and health checks are given a finer-grained control using the Metrics/ThreadDump and Metrics/HealthCheck permissions respectively.

The finer-grained control is because thread dumps and health checks may expose information about job names or build nodes which may be against organization security policies.

Machine access

Access to the Metrics Servlet can also be provided by issuing API keys. API keys can be configured from the CloudBees CI global configuration page (Manage Jenkins > Configure System) under the Metrics section. Multiple access keys can be generated and permissions associated with those keys can also be restricted at this level.

Alternatively, Metrics can be restricted to users with a specified access key to the metrics. This configuration can be set up using the CloudBees CI global configuration page (Manage Jenkins > Configure System) under the Metrics section. Multiple access keys can be generated, and access keys’ permissions can be restricted at this level.

Each API key can be configured with unique permissions for the four servlets that the Dropwizard Metrics Servlet offers and each API key can be configured with its own CORS supported origins.

HTTP GET requests use the base URL $JENKINS_URL/metrics/$KEY/
HTTP POST requests use the base URL $JENKINS_URL/metrics/ with the key provided by a standard URL encoded form parameter called key

Endpoints and methods

Table 1. Metrics endpoints and methods
Endpoint	Required permissions	Description	Parameters
GET `${JENKINS_URL}/metrics/currentUser/metrics`	Metrics.VIEW	Returns metrics in JSON format.	Name: pretty Parameter type: Query string parameter Data type: boolean Description: The pretty parameter returns a more human-readable JSON format.
GET `${JENKINS_URL}/metrics/currentUser/healthcheck`	Metrics.HEALTHCHECK	Returns health check details in JSON format.	Name: pretty Parameter type: Query string parameter Data type: boolean Description: The pretty parameter returns a more human-readable JSON format.
GET `${JENKINS_URL}/metrics/currentUser/threads`	Metrics.THREADDUMP	Returns thread dump details.	none
GET `${JENKINS_URL}/metrics/currentUser/ping`	none	Returns "pong".	none

Request examples

Table 2. Metrics Request examples
Endpoint	Request example
GET `/metrics/currentUser/metrics`	`curl --user "admin:rG57xFa2eFrCeWjG4NKU5QMJeW9TzfSkym" -XGET "https://my-operation-center.com/cjoc/metrics/currentUser/metrics?pretty=true"` ▼
GET `/metrics/currentUser/healthcheck`	`curl --user "admin:rG57xFa2eFrCeWjG4NKU5QMJeW9TzfSkym" -XPOST "https://my-operation-center.com/cjoc/metrics/currentUser/healthcheck?pretty=true"` ▼
GET `/metrics/currentUser/threads`	`curl --user "admin:rG57xFa2eFrCeWjG4NKU5QMJeW9TzfSkym" -XPOST "https://my-operation-center.com/cjoc/metrics/currentUser/threads?pretty=true"` ▼
GET `/metrics/currentUser/ping`	`curl --user "admin:rG57xFa2eFrCeWjG4NKU5QMJeW9TzfSkym" -XPOST "https://my-operation-center.com/cjoc/metrics/currentUser/ping"` ▼

In the request examples "admin" is the name of the user attempting to send the request and "https://my-operations-center.com/cjoc/" is the url for the operations center.

Response examples

The sample responses for GET /metrics/currentUser/metrics and GET /metrics/currentUser/threads are lengthy and therefore not fully included in this documentation.

Sample GET /metrics/currentUser/metrics and GET /metrics/currentUser/threads responses are located in the CloudBees documentation samples repo on GitHub.

The metrics response is comprised of the version as well as five objects, representing the different metrics types described in the Response model.

GET /metrics/currentUser/metrics sample response:

{
    "version": "4.0.0",
    "gauges": {...},
    "counters": {...},
    "histograms": {...},
    "meters": {...},
    "timers": {...}
}▼

GET /metrics/currentUser/healthcheck sample response:

{
    "disk-space": {
        "healthy": true
    },
    "plugins": {
        "healthy": false,
        "message": "There are 11 failed plugins: operations-center-server; operations-center-updatecenter; operations-center-monitoring; operations-center-clusterops; master-provisioning-core; operations-center-jnlp-controller; operations-center-sso; operations-center-rbac; master-provisioning-kubernetes; bluesteel-cjoc; operations-center-kubernetes-cloud"
    },
    "temporary-space": {
        "healthy": true
    },
    "thread-deadlock": {
        "healthy": true
    }
}▼

Response model

The following is a very basic set of standard servlets provided by Dropwizard:

Metrics: The Metrics servlet returns the metrics in JSON format. There is also support for JSONP format by including Content-Type: text/javascript in the request.
Ping: The Ping servlet returns the text "pong" and a HTTP/200 status code.
Threads: The Thread servlet returns a thread dump from the master only.
Healthcheck: The Healthcheck servlet runs the healthchecks defined against the Metrics API and returns a detailed status in JSON (or JSONP) format, while the high level status is reported by the HTTP status code.

Metrics

The metrics JSON is organized into following five metrics types:

gauges: a gauge is an instantaneous measurement of a value.
counters: a counter is a gauge that tracks the count of something.
histograms: a histogram measures the statistical distribution of values in a stream of data. Histograms also maintain a reservoir sample of the stream data. In the Jenkins Metrics plugin the standard metric histograms use exponentially decaying reservoirs based on a forward-decaying priority reservoir with an exponential weighting towards newer data. Unlike some other exponentially decaying reservoirs, this strategy has the advantage of maintaining a statistically representative sampling reservoir. Histograms provide the following metrics:
- the number of observed values
- the average of all observed values
- the standard deviation of observed values
- the minimum observed value
- the maximum observed value
- the 50th percentile observed value
- the 75th percentile observed value
- the 95th percentile observed value
- the 98th percentile observed value
- the 99th percentile observed value
- the 99.9th percentile observed value
meters: a meter measures the rate of events over time. Meters provide the following metrics:
- the number of observed events
- the average rate of all observed events
- the average rate of observed events in the past minute
- the average rate of observed events in the past five minutes
- the average rate of observed events in the past fifteen minutes
timers: a timer is basically a histogram of the duration of events coupled with a meter of the rate of the event occurrence. Timers also maintain a exponentially decaying reservoir sample of the event duration data. These exponentially decaying reservoirs use a forward-decaying priority reservoir with an exponential weighting towards newer data. Unlike some other exponentially decaying reservoirs this strategy has the advantage of maintaining a statistically representative sampling reservoir. Timers provide the following metrics:
- the number of observed events
- the average rate of all observed observed
- the average rate of observed events in the past minute
- the average rate of observed events in the past five minutes
- the average rate of observed events in the past fifteen minutes
- the average duration of all observed events
- the standard deviation of observed event durations
- the minimum observed event duration
- the maximum observed event duration
- the 50th percentile observed event duration
- the 75th percentile observed event duration
- the 95th percentile observed event duration
- the 98th percentile observed event duration
- the 99th percentile observed event duration
- the 99.9th percentile observed event duration

gauges

Table 3. Metrics guages response model
Element	Type	Category	Description
jenkins.executor.count.value	object	Jenkins specific metrics	The number of executors available to Jenkins. This is corresponds to the sum of all the executors of all the on-line nodes.
jenkins.executor.free.value	object	Jenkins specific metrics	The number of executors available to Jenkins that are not currently in use.
jenkins.executor.in-use.value	object	Jenkins specific metrics	The number of executors available to Jenkins that are currently in use.
jenkins.health-check.count	object	Jenkins specific metrics	The number of health checks associated with the HealthCheckRegistry defined within the Jenkins Metrics plugin.
jenkins.health-check.inverse-score	object	Jenkins specific metrics	The ratio of health checks reporting failure to the total number of health checks. Larger values indicate decreasing health as measured by the health checks. (This is a value between 0 and 1 inclusive).
jenkins.health-check.score	object	Jenkins specific metrics	The ratio of health checks reporting success to the total number of health checks. Larger values indicate increasing health as measured by the health checks. (This is a value between 0 and 1 inclusive).
jenkins.job.count.value	object	Jenkins specific metrics	The number of jobs in Jenkins.
jenkins.node.count.value	object	Jenkins specific metrics	The number of build nodes available to Jenkins, both on-line and off-line.
jenkins.node.offline.value	object	Jenkins specific metrics	The number of build nodes available to Jenkins but currently off-line.
jenkins.node.online.value	object	Jenkins specific metrics	The number of build nodes available to Jenkins and currently on-line.
jenkins.plugins.active	object	Jenkins specific metrics	The number of plugins in the Jenkins instance that started successfully.
jenkins.plugins.failed	object	Jenkins specific metrics	The number of plugins in the Jenkins instance that failed to start. A value other than 0 is typically indicative of a potential issue within the Jenkins installation that will either be solved by explicitly disabling the plugin(s) or by resolving the plugin dependency issues.
jenkins.plugins.inactive	object	Jenkins specific metrics	The number of plugins in the Jenkins instance that are not currently enabled.
jenkins.plugins.withUpdate	object	Jenkins specific metrics	The number of plugins in the Jenkins instance that have an newer version reported as available in the current Jenkins update center metadata held by Jenkins. This value is not indicative of an issue with Jenkins but high values can be used as a trigger to review the plugins with updates with a view to seeing whether those updates potentially contain fixes for issues that could be affecting your Jenkins instance.
jenkins.queue.blocked.value	object	Jenkins specific metrics	The number of jobs that are in the Jenkins build queue and currently in the blocked state.
jenkins.queue.buildable.value	object	Jenkins specific metrics	The number of jobs that are in the Jenkins build queue and currently in the blocked state.
jenkins.queue.pending.value	object	Jenkins specific metrics	The number of jobs that are in the Jenkins build queue and currently in the blocked state.
jenkins.queue.size.value	object	Jenkins specific metrics	The number of jobs that are in the Jenkins build queue.
jenkins.queue.stuck.value	object	Jenkins specific metrics	The number of jobs that are in the Jenkins build queue and currently in the blocked state.
system.cpu.load	object	System and Java Virtual Machine metrics	The system load on the Jenkins master as reported by the JVM’s Operating System JMX MBean. The calculation of system load is operating system dependent. Typically this is the sum of the number of processes that are currently running plus the number that are waiting to run. This is typically comparable against the number of CPU cores.
vm.blocked.count	object	System and Java Virtual Machine metrics	The number of threads in the Jenkins master JVM that are currently blocked waiting for a monitor lock.
vm.count	object	System and Java Virtual Machine metrics	The total number of threads in the Jenkins master JVM. This is the sum of: `vm.blocked.count`, `vm.new.count`, `vm.runnable.count`, `vm.terminated.count`, `vm.timed_waiting.count` and `vm.waiting.count`.
vm.cpu.load	object	System and Java Virtual Machine metrics	The rate of CPU time usage by the JVM per unit time on the Jenkins master. This is equivalent to the number of CPU cores being used by the Jenkins master JVM.
vm.daemon.count	object	System and Java Virtual Machine metrics	The number of threads in the Jenkins master JVM that are marked as Daemon threads.
vm.deadlocks	object	System and Java Virtual Machine metrics	The number of threads that have a currently detected deadlock with at least one other thread.
vm.file.descriptor.ratio	object	System and Java Virtual Machine metrics	The ratio of used to total file descriptors. (This is a value between 0 and 1 inclusive).
vm.memory.heap.committed	object	System and Java Virtual Machine metrics	The amount of memory, in the heap that is used for object allocation, that is guaranteed by the operating system as available for use by the Jenkins master JVM. (Units of measurement: bytes).
vm.memory.heap.init	object	System and Java Virtual Machine metrics	The amount of memory, in the heap that is used for object allocation, that the Jenkins master JVM initially requested from the operating system. (Units of measurement: bytes).
vm.memory.heap.max	object	System and Java Virtual Machine metrics	The maximum amount of memory, in the heap that is used for object allocation, that the Jenkins master JVM is allowed to request from the operating system. This amount of memory is not guaranteed to be available for memory management if it is greater than the amount of committed memory. The JVM may fail to allocate memory even if the amount of used memory does not exceed this maximum size. (Units of measurement: bytes).
vm.memory.heap.usage	object	System and Java Virtual Machine metrics	The ratio of `vm.memory.heap.used` to `vm.memory.heap.max`. (This is a value between 0 and 1 inclusive).
vm.memory.heap.used	object	System and Java Virtual Machine metrics	The amount of memory, in the heap that is used for object allocation, that the Jenkins master JVM is currently using.(Units of measurement: bytes).
vm.memory.non-heap.committed	object	System and Java Virtual Machine metrics	The amount of memory, outside the heap that is used for object allocation, that is guaranteed by the operating system as available for use by the Jenkins master JVM. (Units of measurement: bytes).
vm.memory.non-heap.init	object	System and Java Virtual Machine metrics	The amount of memory, outside the heap that is used for object allocation, that the Jenkins master JVM initially requested from the operating system. (Units of measurement: bytes).
vm.memory.non-heap.max	object	System and Java Virtual Machine metrics	The maximum amount of memory, outside the heap that is used for object allocation, that the Jenkins master JVM is allowed to request from the operating system. This amount of memory is not guaranteed to be available for memory management if it is greater than the amount of committed memory. The JVM may fail to allocate memory even if the amount of used memory does not exceed this maximum size. (Units of measurement: bytes).
vm.memory.non-heap.usage	object	System and Java Virtual Machine metrics	The ratio of `vm.memory.non-heap.used` to `vm.memory.non-heap.max`. (This is a value between 0 and 1 inclusive).
vm.memory.non-heap.used	object	System and Java Virtual Machine metrics	The amount of memory, outside the heap that is used for object allocation, that the Jenkins master JVM is currently using. (Units of measurement: bytes).
vm.memory.pools..usage	objects	System and Java Virtual Machine metrics	The usage level of the memory pool, where a value of 0 represents an unused pool while a value of 1 represents a pool that is at capacity. The names are supplied by and dependent on the JVM. There will be one metric for each of the memory pools reported by the JVM.
vm.memory.total.committed	object	System and Java Virtual Machine metrics	The total amount of memory that is guaranteed by the operating system as available for use by the Jenkins master JVM. (Units of measurement: bytes).
vm.memory.total.init	object	System and Java Virtual Machine metrics	The total amount of memory that the Jenkins master JVM initially requested from the operating system. (Units of measurement: bytes).
vm.memory.total.max	object	System and Java Virtual Machine metrics	The maximum amount of memory that the Jenkins master JVM is allowed to request from the operating system. This amount of memory is not guaranteed to be available for memory management if it is greater than the amount of committed memory. The JVM may fail to allocate memory even if the amount of used memory does not exceed this maximum size. (Units of measurement: bytes).
vm.memory.total.used	object	System and Java Virtual Machine metrics	The total amount of memory that the Jenkins master JVM is currently using.(Units of measurement: bytes).
vm.new.count	object	System and Java Virtual Machine metrics	The number of threads in the Jenkins master JVM that have not currently started execution.
vm.runnable.count	object	System and Java Virtual Machine metrics	The number of threads in the Jenkins master JVM that are currently executing in the JVM. Some of these threads may be waiting for other resources from the operating system such as the processor.
vm.terminated.count	object	System and Java Virtual Machine metrics	The number of threads in the Jenkins master JVM that have completed execution.
vm.timed_waiting.count	object	System and Java Virtual Machine metrics	The number of threads in the Jenkins master JVM that have suspended execution for a defined period of time.
vm.uptime.milliseconds	object	System and Java Virtual Machine metrics	The number of milliseconds since the Jenkins master JVM started.
vm.waiting.count	object	System and Java Virtual Machine metrics	The number of threads in the Jenkins master JVM that are currently waiting on another thread to perform a particular action.

counters

Table 4. Metrics counters response model
Element	Type	Category	Description
http.activeRequests	object	Web UI metrics	The number of currently active requests against the Jenkins master Web UI.

histograms

Table 5. Metrics histograms response model
Element	Type	Category	Description
jenkins.executor.count.history	object	Jenkins specific metrics	The historical statistics of `jenkins.executor.count.value`.
jenkins.executor.free.history	object	Jenkins specific metrics	The historical statistics of `jenkins.executor.free.value`.
jenkins.executor.in-use.history	object	Jenkins specific metrics	The number of executors available to Jenkins that are currently in use.
jenkins.job.count.history	object	Jenkins specific metrics	The historical statistics of `jenkins.job.count.value`.
jenkins.node.count.history	object	Jenkins specific metrics	The historical statistics of `jenkins.node.count.value`.
jenkins.node.offline.history	object	Jenkins specific metrics	The historical statistics of `jenkins.node.offline.value`.
jenkins.node.online.history	object	Jenkins specific metrics	The historical statistics of `jenkins.node.online.value`.
jenkins.queue.blocked.history	object	Jenkins specific metrics	The historical statistics of `jenkins.queue.blocked.value`.
jenkins.queue.buildable.history	object	Jenkins specific metrics	The historical statistics of `jenkins.queue.buildable.value`.
jenkins.queue.pending.history	object	Jenkins specific metrics	The historical statistics of `jenkins.queue.pending.value`.
jenkins.queue.size.history	object	Jenkins specific metrics	The historical statistics of `jenkins.queue.size.value`.
jenkins.queue.stuck.history	object	Jenkins specific metrics	The historical statistics of `jenkins.queue.stuck.value`.
count	number	N/A	The number of observed values.
max	number	N/A	The maximum observed value.
mean	number	N/A	The average of all observed values.
min	number	N/A	The minimum observed value.
p50	number	N/A	The 50th percentile observed value.
p75	number	N/A	The 75th percentile observed value.
p95	number	N/A	The 95th percentile observed value.
p98	number	N/A	The 98th percentile observed value.
p99	number	N/A	The 99th percentile observed value.
p999	number	N/A	The 99.9th percentile observed value.
values	array	N/A	A reservoir sample of stream data.
stddev	number	N/A	The standard deviation of observed values.

meters

Table 6. Metrics meters response model
Element	Type	Category	Description
http.responseCodes.badRequest	object	Web UI metrics	The rate at which the Jenkins master Web UI is responding to requests with a `HTTP/400` status code.
http.responseCodes.created	object	Web UI metrics	The rate at which the Jenkins master Web UI is responding to requests with a `HTTP/201` status code.
http.responseCodes.forbidden	object	Web UI metrics	The rate at which the Jenkins master Web UI is responding to requests with a `HTTP/403` status code.
http.responseCodes.noContent	object	Web UI metrics	The rate at which the Jenkins master Web UI is responding to requests with a `HTTP/204` status code.
http.responseCodes.notFound	object	Web UI metrics	The rate at which the Jenkins master Web UI is responding to requests with a `HTTP/404` status code.
http.responseCodes.notModified	object	Web UI metrics	The rate at which the Jenkins master Web UI is responding to requests with a `HTTP/304` status code.
http.responseCodes.ok	object	Web UI metrics	The rate at which the Jenkins master Web UI is responding to requests with a `HTTP/200` status code.
http.responseCodes.other	object	Web UI metrics	The rate at which the Jenkins master Web UI is responding to requests with a non-informational status code that is not in the list: `HTTP/200`, `HTTP/201`, `HTTP/204`, `HTTP/304`, `HTTP/400`, `HTTP/403`, `HTTP/404`, `HTTP/500`, or `HTTP/503`.
http.responseCodes.serverError	object	Web UI metrics	The rate at which the Jenkins master Web UI is responding to requests with a `HTTP/500` status code.
http.responseCodes.serviceUnavailable	object	Web UI metrics	The rate at which the Jenkins master Web UI is responding to requests with a `HTTP/503` status code.
jenkins.job.scheduled	object	Jenkins specific metrics	The rate at which jobs are scheduled. If a job is already in the queue and an identical request for scheduling the job is received then Jenkins will coalesce the two requests. This metric gives a reasonably pure measure of the load requirements of the Jenkins master as it is unaffected by the number of executors available to the system. Multiplying this metric by `jenkins.job.building.duration` gives an approximate measure of the number of executors required in order to ensure that every build request results in a build. A more accurate measure can be obtained from a job-by-job summation of the scheduling rate for that job and the average build duration of that job. The most accurate measure would require maintaining separate sums partitioned by the labels that each job can run against in order to determine the number of each type of executor required. Such calculations assume that: every build node is equivalent and/or the build times are comparable across all build nodes; and build times are unaffected by other jobs running in parallel on other executors on the same node. However in most cases even the basic result from multiplying `jenkins.job.scheduled` by `jenkins.job.building.duration` gives a reasonable result. Where larger than `jenkins.executor.count.value` by more than 10-15% the Jenkins build queue is typically observed to grow rapidly until most jobs have at least one build request sitting in the build queue. Whereas when less than jenkins.executor.count.value by at least 20-25% the build queue will tend to remain small, except for those cases where there are a large number of build jobs fighting for a small number of executors on nodes with specific labels.
count	number	N/A	The number of observed events.
m15_rate	number	N/A	The average rate of observed events in the past fifteen minutes.
m1_rate	number	N/A	The average rate of observed events in the past minute.
m5_rate	number	N/A	The average rate of observed events in the past five minutes.
mean_rate	number	N/A	The average rate of all observed events.
units	string	N/A	The units used for calculations - "events/minute".

timers

Table 7. Metrics timers response model
Element	Type	Category	Description
http.requests	object	Web UI metrics	The rate at which the Jenkins master Web UI is receiving requests and the time spent generating the corresponding responses.
jenkins.health-check.duration	object	Jenkins specific metrics	The rate at which the health checks are being run and the duration of each health check run. The Jenkins Metrics plugin, by default, will run the health checks once per minute. The frequency can be controlled by the `jenkins.metrics.api.Metrics.HEALTH_CHECK_INTERVAL_MINS` system property. In addition, the Metrics plugin’s Operational Servlet can be used to request the health checks be run on demand.
jenkins.job.blocked.duration	object	Jenkins specific metrics	The rate at which jobs in the build queue enter the blocked state and the amount of time they spend in that state.
jenkins.job.building.duration	object	Jenkins specific metrics	The rate at which jobs are built and the time they spend building.
jenkins.job.queuing.duration	object	Jenkins specific metrics	The rate at which jobs are queued and the total time they spend in the build queue.
jenkins.job.total.duration	object	Jenkins specific metrics	The rate at which jobs are queued and the total time they spend from entering the build queue to completing building.
jenkins.job.waiting.duration	object	Jenkins specific metrics	The rate at which jobs enter the quiet period and the total amount of time that jobs spend in their quiet period. Jenkins allows configuring a quiet period for most job types. While in the quiet period multiple identical requests for building the job will be coalesced. Traditionally this was used with source control systems that do not provide an atomic commit facility - such as CVS - in order to ensure that all the files in a large commit were picked up as a single build. With more modern source control systems the quiet period can still be useful, for example to ensure that push notification of the came commit via redundant parallel notification paths get coalesced.
count	number	N/A	The number of observed events.
max	number	N/A	The maximum observed event duration.
mean	number	N/A	The average rate of all observed events.
min	number	N/A	The minimum observed event duration.
p50	number	N/A	The 50th percentile observed event duration.
p75	number	N/A	The 75th percentile observed event duration.
p95	number	N/A	The 95th percentile observed event duration.
p98	number	N/A	The 98th percentile observed event duration.
p99	number	N/A	The 99th percentile observed event duration.
p999	number	N/A	The 99.9th percentile observed event duration.
values	array	N/A	An exponentially decaying reservoir sample of the event duration data.
stddev	number	N/A	The standard deviation of observed event durations.
m15_rate	number	N/A	The average rate of observed events in the past fifteen minutes.
m1_rate	number	N/A	The average rate of observed events in the past minute.
m5_rate	number	N/A	The average rate of observed events in the past five minutes.
mean_rate	number	N/A	The average rate of all observed events.
duration_units	string	N/A	The units used for calculations - "seconds".
rate_units	string	N/A	The units used for calculations - "calls/minutes".

Ping

The Ping servlet returns the text "pong" and a HTTP/200 status code.

Threads

The Threads servlet returns a thread dump from the master only.

Healthcheck

Table 8. Metrics heathcheck response model
Element	Type	Category	Description
disk-space	object	Standard health checks	Returns FAIL if any of the Jenkins disk space monitors are reporting the disk space as less than the configured threshold. The message will reference the first node which fails this check. There may be other nodes that fail the check, but this health check is designed to fail fast.
plugins	object	Standard health checks	Returns FAIL if any of the Jenkins plugins failed to start. A failure is typically indicative of a potential issue within the Jenkins installation that will either be solved by explicitly disabling the failing plugin(s) or by resolving the corresponding plugin dependency issues.
temporary-space	object	Standard health checks	Returns FAIL if any of the Jenkins temporary space monitors are reporting the temporary space as less than the configured threshold. The message will reference the first node which fails this check. There may be other nodes that fail the check, but this health check is designed to fail fast.
thread-deadlock	object	Standard health checks	Returns FAIL if there are any deadlocked threads in the Jenkins master JVM.

Status and error codes

Table 9. Status and error codes
Code	Description
200	Success
403	Not authorized.
404	The provided endpoint or method cannot be found.
500	Server error.