Hello Everybody,
I am happy to announce release 0.20.0 of Hawkular Metrics. This is a major
release anchored by the inclusion of Hawkular Alerting
<
https://github.com/hawkular/hawkular-alerts> in the distribution, a brand
new compression algorithm, and numerous API enhancements and fixes.
*Hawkular Metrics + Alerting*
Hawkular Metrics now includes Hawkular Alerting out of the box; it's no
longer necessary to install and manage two separate components. Hawkular
Metrics delivers a single EAR file containing components from both
projects. Incoming metric data is efficiently filtered and evaluated,
generating alerts and events for defined triggers. The combined EAR
artifact is the primary binary distribution of Hawkular Metrics going
forward. For more details: HWKMETRICS-491
<
https://issues.jboss.org/browse/HWKMETRICS-491>
Hawkular Alerting Details
- Version 1.2.1
<
https://issues.jboss.org/browse/HWKALERTS/fixforversion/12331699/> is
included in this release
- Project details and repository: Hawkular Alerting - Github
<
https://github.com/hawkular/hawkular-alerts>
- Documentation: Hawkular Alerting REST API Documentation
<
http://www.hawkular.org/docs/rest/rest-alerts.html>, Hawkular Alerting
Examples
<
https://github.com/hawkular/hawkular-alerts/tree/master/examples>, Hawkular
Alerting Developer Guide
<
http://www.hawkular.org/community/docs/developer-guide/alerts.html>
Deployment Notes
1. Deployment Naming
- The new EAR should be deployed as 'hawkular-metrics.ear' in
WildFly. This naming is required to allow for proper dependencies to be
established by the EAR components.
2. standalone.xml Configuration
- The following snippet must be added to standalone.xml to support
the Hawkular Alerting component. Add this additional
cache-container entry
after the existing cache-container entries:
<cache-container name="hawkular-alerts"
module="org.jboss.as.clustering.infinispan">
<local-cache name="partition"/>
<local-cache name="triggers"/>
<local-cache name="data"/>
<local-cache name="publish"/>
<local-cache name="schema"/>
</cache-container>
Usage Notes
To use Hawkular Alerting with Hawkular Metrics there is a naming convention
when defining trigger conditions. For a metric with name 'X', the alerting
DataId to reference it will be '*X',* where the depends on the metric's
type. For example, let's consider a metric with name 'HeapUsed' and type
'gauge'. This example defines a trigger condition to test if the used heap
exceeded 80%: "hm_g_HeapUsed > .8". The 'hm_g' prefix indicates that
HeapUsed is a gauge.
Because Hawkular Metrics allows the same metric name for different types,
the prefix is needed to make clear the target metric. The prefixes are:
- hm_a: availability
- hm_c: counter
- hm_cr: counter rate
- hm_g: gauge
- hm_gr: gauge rate
- hm_s: string
*Compression*
Hawkular Metrics will now compress all the data with a compression scheme
based on Facebook's Gorilla paper. A job will be run every two hours that
compresses data received during the 2 hour block since last compression
(there's one hour time for out-of-order writes to be written to the
Cassandra). These data points are then written to a new storage format
that's designed after the Gorilla compression and also compressed with the
LZ4 algorithm to give even better compression ratio. Benefits include a
faster reading time of larger block of datapoints and very large disk space
savings. For more details: HWKMETRICS-464
<
https://issues.jboss.org/browse/HWKMETRICS-464>
*Other major changes*
-
REST API - Query Improvements
- Querying raw & rate data by tags is now also possible via POST
{metric_type}/query endpoints for all types of metrics (HWKMETRICS-466
<
https://issues.jboss.org/browse/HWKMETRICS-466>)
- Added new POST endpoints for stats gauges/stats/query and
counters/stats/query (HWKMETRICS-465
<
https://issues.jboss.org/browse/HWKMETRICS-465>)
- It is now possible to fetch metric definitions filtered by a list
of ids not just tags (HWKMETRICS-461
<
https://issues.jboss.org/browse/HWKMETRICS-461>)
-
Cassandra Driver Configuration
- Driver configuration options are now exposed for connection and
request timeouts
- Connection timeout can be configured via
CASSANDRA_CONNECTION_TIMEOUT environment variable, or
hawkular-metrics.cassandra.connection.timeout system property; value
is specified in milliseconds and defaults to 5 seconds.
- Request timeout can be configured via CASSANDRA_REQUEST_TIMEOUT
environment variable, or hawkular-metrics.cassandra.request.timeout
system property; value is specified in milliseconds and defaults to 12
seconds.
- For more details: HWKMETRICS-490
<
https://issues.jboss.org/browse/HWKMETRICS-490>
-
Job Scheduler
- Duplicate instances of jobs were wrongly scheduled on server restart
because the job scheduler was not checking if the job was
already scheduled
(HWKMETRICS-461 <
https://issues.jboss.org/browse/HWKMETRICS-461>)
- Triggers now have a delay to properly schedule jobs in the future (
HWKMETRICS-224 <
https://issues.jboss.org/browse/HWKMETRICS-224>)
- Resolved an issue where long running job can miss future executions
because the current execution takes longer than the repeat interval (
HWKMETRICS-477 <
https://issues.jboss.org/browse/HWKMETRICS-477>)
- Prevent execution of a job multiple times for the same execution
time (HWKMETRICS-486 <
https://issues.jboss.org/browse/HWKMETRICS-486>)
- RepeatingTrigger now allows specifying trigger start time (
HWKMETRICS-476 <
https://issues.jboss.org/browse/HWKMETRICS-476>)
-
Admin Endpoints
- Admin related endpoints are going to be protected via an admin token,
to be sent for admin related REST endpoints via Hawkular-Admin-Token
request header
- The first endpoint to be protected by this mechanism is /tenants
since its functionality is cross tenant
- The admin token can be set via command line arguments or
environment variable at container startup; by default it is not set which
means no access to protected endpoints
- This is the foundation for adding more admin related functionality
in upcoming releases (such as Cassandra cluster metrics, system
telemetry,
or admin operations)
- The details:
- system property key: hawkular.metrics.admin-token
- environment variable: ADMIN_TOKEN
- default value: null (admin endpoints are not accessible until
set)
- header name: Hawkular-Admin-Token
- stored in system config using one-way hashing
- For more details: HWKMETRICS-478
<
https://issues.jboss.org/browse/HWKMETRICS-478>
*Hawkular Metrics Clients*
- Python:
https://github.com/hawkular/hawkular-client-python
- Go:
https://github.com/hawkular/hawkular-client-go
- Ruby:
https://github.com/hawkular/hawkular-client-ruby
- Java:
https://github.com/hawkular/hawkular-client-java
*Release Links*
Github Release:
https://github.com/hawkular/hawkular-metrics/releases/tag/0.20.0
JBoss Nexus Maven artifacts:
http://origin-repository.jboss.org/nexus/content/repositories/public/org/
hawkular/metrics/
Jira release tracker:
https://issues.jboss.org/browse/HWKMETRICS/fixforversion/12331360
A big "Thank you" goes to John Sanda, Matt Wringe, Michael Burman, Joel
Takvorian, Jay Shaughnessy, Lucas Ponce, and Heiko Rupp for their project
contributions.
Thank you,
Stefan Negrea