Spark Jobs API

This is a set of endpoints for configuring and running Spark jobs.

Spark job subtypes

For the Spark job type, the available subtypes are listed below.

• Aggregation
  Define an aggregation job.
• Custom Spark job
  Run a custom Spark job.
• Script
  Run a custom Scala script as a Fusion job.

Additional Spark jobs are available with a Fusion AI license.

Spark Configuration Properties

Fusion passes all configuration properties with prefix “spark.” to the Spark master, Spark worker and each Spark application, both for aggregation jobs and custom-scripted processing.

These properties are stored in Fusion’s ZooKeeper and can be updated via requests to Fusion endpoint api/configurations which will update the stored value without restarting the service, therefore existing jobs and SparkContexts will not be affected. The Fusion endpoint api/configurations returns all configured properties for that installation. You can examine spark default configurations in a Unix shell using the utilities curl and grep. Here is an example that checks a local Fusion installation running on port 8764:

curl -u username:password https://FUSION_HOST:8764/api/configurations | grep '"spark.'

  "spark.executor.memory" : "2g",
  "spark.task.maxFailures" : "10",
  "spark.worker.cleanup.appDataTtl" : "7200",
  "spark.worker.cleanup.enabled" : "true",
  "spark.worker.memory" : "2g",

The default SparkContext that Fusion uses for aggregation jobs can be assigned a fraction of cluster resources (executor memory and/or available CPU cores). This allows other applications (such as scripted jobs, or shell sessions) to use the remaining cluster resources even when some aggregation jobs are running. Fusion also supports dynamic allocation for all applications. This can be overridden per application. In practice, this means that even when there is an already running SparkContext with a relatively long idle time (eg. 10 minutes) but there are no active jobs that use it, its resources (CPU cores and executor memory) will be released for use by other applications.

For scripted Spark jobs, users can specify per-job configuration overrides as a set of key / value pairs in a “sparkConfig” property element of a script job configuration, which takes precedence over values stored in ZooKeeper. The following is an example of a scripted job with a “sparkConfig” section:

{
  "id": "scripted_job_example",
  "script": "val rdd = sc.textFile(\"/foo.txt\")\nrdd.count\n",
  "sparkConfig": {
    "spark.cores.max": 2,
    "spark.executor.memory": "1g"
  }
}

The following table lists those Spark configuration properties that Fusion overrides or uses in order to determine applications’ resource allocations.

Property	Description
spark.master.url	By default, left unset. This property is only specified when using an external Spark cluster; when Fusion is using its own standalone Spark cluster, this property is not set.
spark.cores.max	The maximum number of cores across the cluster assigned to the application. If not specified, there is no limit. The default is unset, i.e., an unlimited number of cores.
spark.executor.memory	Amount of memory assigned to each application’s executor. The default is 2G.
spark.scheduler.mode	Controls how tasks are assigned to available resources. Can be either ‘FIFO’ or ‘FAIR’. Default value is ‘FAIR’.
spark.dynamicAllocation.enabled	Boolean - whether or not to enable dynamic allocation of executors. Default value is ‘TRUE’.
spark.shuffle.service.enabled	Boolean - whether or not to enable internal shuffle service for standalone Spark cluster. Default value is ‘TRUE’.
spark.dynamicAllocation.executorIdleTimeout	Number of seconds after which idle executors are removed. Default value is ‘60s’.
spark.dynamicAllocation.minExecutors	Number of executors to leave running even when idle. Default value is 0.
spark.eventLog.enabled	Boolean - whether or not event log is enabled. Event log stores job details and can be accessed after application finishes. Default value is ‘TRUE’.
spark.eventLog.dir	Directory that stores event logs. Default location is $FUSION_HOME/var/spark-eventlog.
spark.eventLog.compress	Boolean - whether or not to compress event log data. Default value is ‘TRUE’.
spark.logConf	Boolean - whether or not to log effective SparkConf of new SparkContext-s. Default value is ‘TRUE’.
spark.deploy.recoveryMode	Default value is ‘ZOOKEEPER’
spark.deploy.zookeeper.url	ZooKeeper connect string. Default value is $FUSION_ZK
spark.deploy.zookeeper.dir	ZooKeeper path, default value is /lucid/spark
spark.worker.cleanup.enabled	Boolean - whether or not to periodically cleanup worker data. Default value is ‘TRUE’.
spark.worker.cleanup.appDataTtl	Time-to-live in seconds. Default value is 86400 (24h).
spark.deploy.retainedApplications	The maximum number of applications to show in the UI. Default value is 50.
spark.deploy.retainedDrivers	The maximum number of drivers. Default value is 50.
spark.worker.timeout	The maximum timeout in seconds allowed before a worker is considered lost. The default value is 30.
spark.worker.memory	The maximum total heap allocated to all executors running on this worker. Defaults to value of the executor memory heap.

Fusion Configuration Properties

Property	Description
fusion.spark.master.port	Spark master job submission port. Default value is 8766.
fusion.spark.master.ui.port	Spark master web UI port. Default value is 8767.
fusion.spark.idleTime	Maximum idle time in seconds, after which the application (ie. SparkContext) is shut down. Default value is 300.
fusion.spark.executor.memory.min	Minimum executor memory in MB. Default value 450Mb, which is sufficient to let Fusion components in application task’s to initialize themselves
fusion.spark.executor.memory.fraction	A float number in range (0.0, 1.0] indicating what portion of spark.executor.memory to allocate to this application. Default value is 1.0.
fusion.spark.cores.fraction	A float number in range (0.0, 1.0] indicating what portion of spark.cores.max to allocate to this application. Default value is 1.0.

To avoid losing your running history, Lucidworks recommends that you start jobs with the Fusion Jobs API rather than the Job-Config-Controller or Job-Controller.