:title: Monitoring
Monitoring
==========
.. _statsd:
Statsd reporting
----------------
Zuul comes with support for the statsd protocol, when enabled and configured
(see below), the Zuul scheduler will emit raw metrics to a statsd receiver
which let you in turn generate nice graphics.
Configuration
~~~~~~~~~~~~~
Statsd support uses the ``statsd`` python module. Note that support
is optional and Zuul will start without the statsd python module
present.
Configuration is in the :attr:`statsd` section of ``zuul.conf``.
Metrics
~~~~~~~
These metrics are emitted by the Zuul :ref:`scheduler`:
.. stat:: zuul.event.<driver>.<type>
:type: counter
Zuul will report counters for each type of event it receives from
each of its configured drivers.
.. stat:: zuul.connection.<connection>
Holds metrics specific to connections. This hierarchy includes:
.. stat:: cache.data_size_compressed
:type: gauge
The number of bytes stored in ZooKeeper for all items in this
connection's change cache.
.. stat:: cache.data_size_uncompressed
:type: gauge
The number of bytes required to for the change cache (the
decompressed value of ``data_size_compressed``).
.. stat:: zuul.tenant.<tenant>.event_enqueue_processing_time
:type: timer
A timer metric reporting the time from when the scheduler receives
a trigger event from a driver until the corresponding item is
enqueued in a pipeline. This measures the performance of the
scheduler in dispatching events.
.. stat:: zuul.tenant.<tenant>.event_enqueue_time
:type: timer
A timer metric reporting the time from when a trigger event was
received from the remote system to when the corresponding item is
enqueued in a pipeline. This includes
:stat:`zuul.tenant.<tenant>.event_enqueue_processing_time` and any
driver-specific pre-processing of the event.
.. stat:: zuul.tenant.<tenant>.management_events
:type: gauge
The size of the tenant's management event queue.
.. stat:: zuul.tenant.<tenant>.reconfiguration_time
:type: timer
A timer metric reporting the time taken to reconfigure a tenant.
This is performed by one scheduler after a tenant reconfiguration
event is received. During this time, all processing of that
tenant's pipelines are halted. This measures that time.
Once the first scheduler completes a tenant reconfiguration, other
schedulers may update their layout in the background without
interrupting processing. That is not reported in this metric.
.. stat:: zuul.tenant.<tenant>.trigger_events
:type: gauge
The size of the tenant's trigger event queue.
.. stat:: zuul.tenant.<tenant>.pipeline
Holds metrics specific to jobs. This hierarchy includes:
.. stat:: <pipeline>
A set of metrics for each pipeline named as defined in the Zuul
config.
.. stat:: event_enqueue_time
:type: timer
The time elapsed from when a trigger event was received from
the remote system to when the corresponding item is enqueued
in a pipeline.
.. stat:: merge_request_time
:type: timer
The amount of time spent waiting for the initial merge
operation(s). This will always include a request to a Zuul
merger to speculatively merge the change, but it may also
include a second request submitted in parallel to identify
the files altered by the change. Includes
:stat:`zuul.tenant.<tenant>.pipeline.<pipeline>.merger_merge_op_time`
and
:stat:`zuul.tenant.<tenant>.pipeline.<pipeline>.merger_files_changes_op_time`.
.. stat:: merger_merge_op_time
:type: timer
The amount of time the merger spent performing a merge
operation. This does not include any of the round-trip time
from the scheduler to the merger, or any other merge
operations.
.. stat:: merger_files_changes_op_time
:type: timer
The amount of time the merger spent performing a files-changes
operation to detect changed files (this is sometimes
performed if the source does not provide this information).
This does not include any of the round-trip time from the
scheduler to the merger, or any other merge operations.
.. stat:: layout_generation_time
:type: timer
The amount of time spent generating a dynamic configuration layout.
.. stat:: job_freeze_time
:type: timer
The amount of time spent freezing the inheritance hierarchy
and parameters of a job.
.. stat:: repo_state_time
:type: timer
The amount of time waiting for a secondary Zuul merger
operation to collect additional information about the repo
state of required projects. Includes
:stat:`zuul.tenant.<tenant>.pipeline.<pipeline>.merger_repo_state_op_time`.
.. stat:: merger_repo_state_op_time
:type: timer
The amount of time the merger spent performing a repo state
operation to collect additional information about the repo
state of required projects. This does not include any of the
round-trip time from the scheduler to the merger, or any
other merge operations.
.. stat:: node_request_time
:type: timer
The amount of time spent waiting for each node request to be
fulfilled.
.. stat:: job_wait_time
:type: timer
How long a job waited for an executor to start running it
after the build was requested.
.. stat:: event_job_time
:type: timer
The total amount of time elapsed from when a trigger event
was received from the remote system until the item's first
job is run. This is only emitted once per queue item, even
if its buildset is reset due to a speculative execution
failure.
.. stat:: all_jobs
:type: counter
Number of jobs triggered by the pipeline.
.. stat:: current_changes
:type: gauge
The number of items currently being processed by this
pipeline.
.. stat:: window
:type: gauge
The configured window size for the pipeline. Note that this
will not change during operation. This value is used to
initialize each :term:`project queue`, and as changes in that
queue succeed or fail, that queue's window will adjust.
.. stat:: handling
:type: timer
The total time taken to refresh and process the pipeline.
This is emitted every time a scheduler examines a pipeline
regardless of whether it takes any actions.
.. stat:: event_process
:type: timer
The time taken to process the event queues for the pipeline.
This is emitted only if there are events to process.
.. stat:: process
:type: timer
The time taken to process the pipeline. This is emitted only
if there were events to process.
.. stat:: data_size_compressed
:type: gauge
The number of bytes stored in ZooKeeper to represent the
serialized state of the pipeline.
.. stat:: data_size_uncompressed
:type: gauge
The number of bytes required to represent the serialized
state of the pipeline (the decompressed value of
``data_size_compressed``).
.. stat:: queue
This hierarchy holds more specific metrics for each
:term:`project queue` in the pipeline.
.. stat:: <queue>
The name of the queue. If the queue is automatically
generated for a single project, the name of the project is
used by default. Embedded ``.`` characters will be
translated to ``_``, and ``/`` to ``.``.
If the queue is configured as per-branch, the metrics
below are omitted and instead found under
:stat:`zuul.tenant.<tenant>.pipeline.<pipeline>.queue.<queue>.branch`.
.. stat:: current_changes
:type: gauge
The number of items currently in this queue.
.. stat:: window
:type: gauge
The window size for the queue. This will change as
individual changes in the queue succeed or fail.
.. stat:: resident_time
:type: timer
A timer metric reporting how long each item has been in
the queue.
.. stat:: total_changes
:type: counter
The number of changes processed by the queue.
.. stat:: branch
If the queue is configured as per-branch, this
hierarchy will be present and will hold stats for each
branch seen.
.. stat:: <branch>
The name of the branch. Embedded ``.`` characters
will be translated to ``_``, and ``/`` to ``.``.
Underneath this key are per-branch values of the
metrics above.
.. stat:: project
This hierarchy holds more specific metrics for each project
participating in the pipeline.
.. stat:: <canonical_hostname>
The canonical hostname for the triggering project.
Embedded ``.`` characters will be translated to ``_``.
.. stat:: <project>
The name of the triggering project. Embedded ``/`` or
``.`` characters will be translated to ``_``.
.. stat:: <branch>
The name of the triggering branch. Embedded ``/`` or
``.`` characters will be translated to ``_``.
.. stat:: job
Subtree detailing per-project job statistics:
.. stat:: <jobname>
The triggered job name.
.. stat:: <result>
:type: counter, timer
A counter for each type of result (e.g., ``SUCCESS`` or
``FAILURE``, ``ERROR``, etc.) for the job. If the
result is ``SUCCESS`` or ``FAILURE``, Zuul will
additionally report the duration of the build as a
timer.
.. stat:: wait_time
:type: timer
How long the job waited for an executor to
start running it after the build was requested.
.. stat:: current_changes
:type: gauge
The number of items of this project currently being
processed by this pipeline.
.. stat:: resident_time
:type: timer
A timer metric reporting how long each item for this
project has been in the pipeline.
.. stat:: total_changes
:type: counter
The number of changes for this project processed by the
pipeline.
.. stat:: read_time
:type: timer
The time spent reading data from ZooKeeper during a single
pipeline processing run.
.. stat:: read_znodes
:type: gauge
The number of ZNodes read from ZooKeeper during a single
pipeline processing run.
.. stat:: read_objects
:type: gauge
The number of Zuul data model objects read from ZooKeeper
during a single pipeline processing run.
.. stat:: read_bytes
:type: gauge
The amount of data read from ZooKeeper during a single
pipeline processing run.
.. stat:: refresh
:type: timer
The time taken to refresh the state from ZooKeeper.
.. stat:: resident_time
:type: timer
A timer metric reporting how long each item has been in the
pipeline.
.. stat:: total_changes
:type: counter
The number of changes processed by the pipeline.
.. stat:: trigger_events
:type: gauge
The size of the pipeline's trigger event queue.
.. stat:: result_events
:type: gauge
The size of the pipeline's result event queue.
.. stat:: management_events
:type: gauge
The size of the pipeline's management event queue.
.. stat:: write_time
:type: timer
The time spent writing data to ZooKeeper during a single
pipeline processing run.
.. stat:: write_znodes
:type: gauge
The number of ZNodes written to ZooKeeper during a single
pipeline processing run.
.. stat:: write_objects
:type: gauge
The number of Zuul data model objects written to ZooKeeper
during a single pipeline processing run.
.. stat:: write_bytes
:type: gauge
The amount of data written to ZooKeeper during a single
pipeline processing run.
.. stat:: zuul.executor.<executor>
Holds metrics emitted by individual executors. The ``<executor>``
component of the key will be replaced with the hostname of the
executor.
.. stat:: merger.<result>
:type: counter
Incremented to represent the status of a Zuul executor's merger
operations. ``<result>`` can be either ``SUCCESS`` or ``FAILURE``.
A failed merge operation which would be accounted for as a ``FAILURE``
is what ends up being returned by Zuul as a ``MERGE_CONFLICT``.
.. stat:: builds
:type: counter
Incremented each time the executor starts a build.
.. stat:: starting_builds
:type: gauge, timer
The number of builds starting on this executor and a timer containing
how long jobs were in this state. These are builds which have not yet
begun their first pre-playbook.
The timer needs special thoughts when interpreting it because it
aggregates all jobs. It can be useful when aggregating it over a longer
period of time (maybe a day) where fast rising graphs could indicate e.g.
IO problems of the machines the executors are running on. But it has to
be noted that a rising graph also can indicate a higher usage of complex
jobs using more required projects. Also comparing several executors might
give insight if the graphs differ a lot from each other. Typically the
jobs are equally distributed over all executors (in the same zone when
using the zone feature) and as such the starting jobs timers (aggregated
over a large enough interval) should not differ much.
.. stat:: running_builds
:type: gauge
The number of builds currently running on this executor. This
includes starting builds.
.. stat:: paused_builds
:type: gauge
The number of currently paused builds on this executor.
.. stat:: phase
Subtree detailing per-phase execution statistics:
.. stat:: <phase>
``<phase>`` represents a phase in the execution of a job.
This can be an *internal* phase (such as ``setup`` or ``cleanup``) as
well as *job* phases such as ``pre``, ``run`` or ``post``.
.. stat:: <result>
:type: counter
A counter for each type of result.
These results do not, by themselves, determine the status of a build
but are indicators of the exit status provided by Ansible for the
execution of a particular phase.
Example of possible counters for each phase are: ``RESULT_NORMAL``,
``RESULT_TIMED_OUT``, ``RESULT_UNREACHABLE``, ``RESULT_ABORTED``.
.. stat:: load_average
:type: gauge
The one-minute load average of this executor, multiplied by 100.
.. stat:: pause
:type: gauge
Indicates if the executor is paused. 1 means paused else 0.
.. stat:: pct_used_hdd
:type: gauge
The used disk on this executor, as a percentage multiplied by 100.
.. stat:: pct_used_inodes
:type: gauge
The used inodes on this executor, as a percentage multiplied by 100.
.. stat:: pct_used_ram
:type: gauge
The used RAM (excluding buffers and cache) on this executor, as
a percentage multiplied by 100.
.. stat:: pct_used_ram_cgroup
:type: gauge
The used RAM (excluding buffers and cache) on this executor allowed by
the cgroup, as percentage multiplied by 100.
.. stat:: zuul.fingergws
Holds metrics related to the Zuul finger gateway component.
.. stat:: online
:type: gauge
The number of Zuul finger gateway processes online.
.. stat:: zuul.nodepool.requests
Holds metrics related to Zuul requests and responses from Nodepool.
States are one of:
*requested*
Node request submitted by Zuul to Nodepool
*canceled*
Node request was canceled by Zuul
*failed*
Nodepool failed to fulfill a node request
*fulfilled*
Nodes were assigned by Nodepool
.. stat:: <state>
:type: timer
Records the elapsed time from request to completion for states
`failed` and `fulfilled`. For example,
``zuul.nodepool.request.fulfilled.mean`` will give the average
time for all fulfilled requests within each ``statsd`` flush
interval.
A lower value for `fulfilled` requests is better. Ideally,
there will be no `failed` requests.
.. stat:: <state>.total
:type: counter
Incremented when nodes are assigned or removed as described in
the states above.
.. stat:: <state>.size.<size>
:type: counter, timer
Increments for the node count of each request. For example, a
request for 3 nodes would use the key
``zuul.nodepool.requests.requested.size.3``; fulfillment of 3
node requests can be tracked with
``zuul.nodepool.requests.fulfilled.size.3``.
The timer is implemented for ``fulfilled`` and ``failed``
requests. For example, the timer
``zuul.nodepool.requests.failed.size.3.mean`` gives the average
time of 3-node failed requests within the ``statsd`` flush
interval. A lower value for `fulfilled` requests is better.
Ideally, there will be no `failed` requests.
.. stat:: <state>.label.<label>
:type: counter, timer
Increments for the label of each request. For example, requests
for `centos7` nodes could be tracked with
``zuul.nodepool.requests.requested.centos7``.
The timer is implemented for ``fulfilled`` and ``failed``
requests. For example, the timer
``zuul.nodepool.requests.fulfilled.label.centos7.mean`` gives
the average time of ``centos7`` fulfilled requests within the
``statsd`` flush interval. A lower value for `fulfilled`
requests is better. Ideally, there will be no `failed`
requests.
.. stat:: zuul.nodepool
.. stat:: current_requests
:type: gauge
The number of outstanding nodepool requests from Zuul. Ideally
this will be at zero, meaning all requests are fulfilled.
Persistently high values indicate more testing node resources
would be helpful.
.. stat:: tenant.<tenant>.current_requests
:type: gauge
The number of outstanding nodepool requests from Zuul drilled down by
<tenant>. If a tenant for a node request cannot be determed, it is
reported as ``unknown``. This relates to
``zuul.nodepool.current_requests``.
.. stat:: zuul.nodepool.resources
Holds metrics about resource usage by tenant or project if resources
of nodes are reported by nodepool.
.. stat:: in_use
Holds metrics about resources currently in use by a build.
.. stat:: tenant
Holds resource usage metrics by tenant.
.. stat:: <tenant>.<resource>
:type: counter, gauge
Counter with the summed usage by tenant as <resource> seconds and
gauge with the currently in use resources by tenant.
.. stat:: project
Holds resource usage metrics by project.
.. stat:: <project>.<resource>
:type: counter, gauge
Counter with the summed usage by project as <resource> seconds and
gauge with the currently used resources by project.
.. stat:: total
Holds metrics about resources allocated in total. This includes
resources that are currently in use, allocated but not yet in use, and
scheduled to be deleted.
.. stat:: tenant
Holds resource usage metrics by tenant.
.. stat:: <tenant>.<resource>
:type: gauge
Gauge with the currently used resources by tenant.
.. stat:: zuul.mergers
Holds metrics related to Zuul mergers.
.. stat:: online
:type: gauge
The number of Zuul merger processes online.
.. stat:: jobs_running
:type: gauge
The number of merge jobs running.
.. stat:: jobs_queued
:type: gauge
The number of merge jobs waiting for a merger. This should
ideally be zero; persistent higher values indicate more merger
resources would be useful.
.. stat:: zuul.executors
Holds metrics related to unzoned executors.
This is a copy of :stat:`zuul.executors.unzoned`. It does not
include information about zoned executors.
.. warning:: The metrics at this location are deprecated and will
be removed in a future version. Please begin using
:stat:`zuul.executors.unzoned` instead.
.. stat:: online
:type: gauge
The number of Zuul executor processes online.
.. stat:: accepting
:type: gauge
The number of Zuul executor processes accepting new jobs.
.. stat:: jobs_running
:type: gauge
The number of executor jobs running.
.. stat:: jobs_queued
:type: gauge
The number of jobs allocated nodes, but queued waiting for an
executor to run on. This should ideally be at zero; persistent
higher values indicate more executor resources would be useful.
.. stat:: unzoned
Holds metrics related to unzoned executors.
.. stat:: online
:type: gauge
The number of unzoned Zuul executor processes online.
.. stat:: accepting
:type: gauge
The number of unzoned Zuul executor processes accepting new
jobs.
.. stat:: jobs_running
:type: gauge
The number of unzoned executor jobs running.
.. stat:: jobs_queued
:type: gauge
The number of jobs allocated nodes, but queued waiting for an
unzoned executor to run on. This should ideally be at zero;
persistent higher values indicate more executor resources
would be useful.
.. stat:: zone
Holds metrics related to zoned executors.
.. stat:: <zone>.online
:type: gauge
The number of Zuul executor processes online in this zone.
.. stat:: <zone>.accepting
:type: gauge
The number of Zuul executor processes accepting new jobs in
this zone.
.. stat:: <zone>.jobs_running
:type: gauge
The number of executor jobs running in this zone.
.. stat:: <zone>.jobs_queued
:type: gauge
The number of jobs allocated nodes, but queued waiting for an
executor in this zone to run on. This should ideally be at
zero; persistent higher values indicate more executor
resources would be useful.
.. stat:: zuul.scheduler
Holds metrics related to the Zuul scheduler.
.. stat:: online
:type: gauge
The number of Zuul scheduler processes online.
.. stat:: eventqueues
Holds metrics about the event queue lengths in the Zuul scheduler.
.. stat:: management
:type: gauge
The size of the current reconfiguration event queue.
.. stat:: connection.<connection-name>
:type: gauge
The size of the current connection event queue.
.. stat:: run_handler
:type: timer
A timer metric reporting the time taken for one scheduler run
handler iteration.
.. stat:: time_query
:type: timer
Each time the scheduler performs a query against the SQL
database in order to determine an estimated time for a job, it
emits this timer of the duration of the query. Note this is a
performance metric of how long the SQL query takes; it is not
the estimated time value itself.
.. stat:: zuul.web
Holds metrics related to the Zuul web component.
.. stat:: online
:type: gauge
The number of Zuul web processes online.
.. stat:: server.<hostname>
Holds metrics from a specific zuul-web server.
.. stat:: threadpool
Metrics related to the web server thread pool.
.. stat:: idle
:type: gauge
The number of idle workers.
.. stat:: queue
:type: gauge
The number of requests queued for workers.
.. stat:: streamers
:type: gauge
The number of log streamers currently in operation.
As an example, given a job named `myjob` in `mytenant` triggered by a
change to `myproject` on the `master` branch in the `gate` pipeline
which took 40 seconds to build, the Zuul scheduler will emit the
following statsd events:
* ``zuul.tenant.mytenant.pipeline.gate.project.example_com.myproject.master.job.myjob.SUCCESS`` +1
* ``zuul.tenant.mytenant.pipeline.gate.project.example_com.myproject.master.job.myjob.SUCCESS`` 40 seconds
* ``zuul.tenant.mytenant.pipeline.gate.all_jobs`` +1
Prometheus monitoring
---------------------
Zuul comes with support to start a prometheus_ metric server to be added as
prometheus's target.
.. _prometheus: https://prometheus.io/docs/introduction/overview/
Configuration
~~~~~~~~~~~~~
To enable the service, set the ``prometheus_port`` in a service section of
``zuul.conf``. For example setting :attr:`scheduler.prometheus_port` to 9091
starts a HTTP server to expose metrics to a prometheus services at:
http://scheduler:9091/metrics
Metrics
~~~~~~~
These metrics are exposed by default:
.. stat:: process_virtual_memory_bytes
:type: gauge
.. stat:: process_resident_memory_bytes
:type: gauge
.. stat:: process_open_fds
:type: gauge
.. stat:: process_start_time_seconds
:type: gauge
.. stat:: process_cpu_seconds_total
:type: counter
On web servers the following additional metrics are exposed:
.. stat:: web_threadpool_idle
:type: gauge
The number of idle workers in the thread pool.
.. stat:: web_threadpool_queue
:type: gauge
The number of requests queued for thread pool workers.
.. stat:: web_streamers
:type: gauge
The number of log streamers currently in operation.
.. _prometheus_liveness:
Liveness Probes
~~~~~~~~~~~~~~~
The Prometheus server also supports liveness and ready probes at the
following URIS:
.. path:: health/live
Returns 200 as long as the process is running.
.. path:: health/ready
Returns 200 if the process is in `RUNNING` or `PAUSED` states.
Otherwise, returns 503. Note that 503 is returned for
`INITIALIZED`, so this may be used to determine when a component
has completely finished loading configuration.
.. path:: health/status
This always returns 200, but includes the component status as the
text body of the response.