Local Properties — Creating Logical Job Groups¶
The purpose of local properties concept is to create logical groups of jobs by means of properties that (regardless of the threads used to submit the jobs) makes the separate jobs launched from different threads belong to a single logical group.
You can <
NOTE: Propagating local properties to workers starts when
SparkContext is requested to SparkContext.md#runJob[run] or SparkContext.md#submitJob[submit] a Spark job that in turn scheduler:DAGScheduler.md#runJob[passes them along to
NOTE: Local properties is used to spark-scheduler-FairSchedulableBuilder.md#spark.scheduler.pool[group jobs into pools in FAIR job scheduler by spark.scheduler.pool per-thread property] and in spark-sql-SQLExecution.md#withNewExecutionId[SQLExecution.withNewExecutionId Helper Methods]
A common use case for the local property concept is to set a local property in a thread, say spark-scheduler-FairSchedulableBuilder.md[spark.scheduler.pool], after which all jobs submitted within the thread will be grouped, say into a pool by FAIR job scheduler.
val rdd = sc.parallelize(0 to 9)
// these two jobs (one per action) will run in the myPool pool rdd.count rdd.collect
// this job will run in the default pool rdd.count
=== [[localProperties]] Local Properties --
localProperties is a
protected[spark] property of a SparkContext.md[SparkContext] that are the properties through which you can create logical job groups.
=== [[setLocalProperty]] Setting Local Property --
setLocalProperty(key: String, value: String): Unit¶
key local property to
key property is removed from <
=== [[getLocalProperty]] Getting Local Property --
getLocalProperty(key: String): String¶
getLocalProperty gets a local property by
key in this thread. It returns
key is missing.
=== [[getLocalProperties]] Getting Local Properties --
getLocalProperties is a
private[spark] method that gives access to <
setLocalProperties(props: Properties): Unit¶
setLocalProperties is a
private[spark] method that sets
props as <