Package org.apache.drill.exec.work.foreman

Class Foreman

java.lang.Object

org.apache.drill.exec.work.foreman.Foreman

All Implemented Interfaces:

Runnable

public class Foreman
extends Object
implements Runnable

Foreman manages all the fragments (local and remote) for a single query where this is the driving/root node. The flow is as follows:

• While Foreman is initialized query is in preparing state.
• Foreman is submitted as a runnable.
• Runnable does query planning.
• Runnable submits query to be enqueued.
• The Runnable's run() completes, but the Foreman stays around to listen to state changes.
• Once query is enqueued, starting fragments are sent out.
• Status listener are activated
• Foreman listens for state change messages.
• State change messages can drive the state to FAILED or CANCELED, in which case messages are sent to running fragments to terminate.
• When all fragments is completed, state change messages drive the state to COMPLETED.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	Foreman.ForemanResult	Manages the end-state processing for Foreman.
static class	Foreman.PhysicalFromLogicalExplain
static enum	Foreman.ProfileOption

Constructor Summary

Constructors

Constructor	Description
Foreman(WorkManager.WorkerBee bee, DrillbitContext drillbitContext, UserClientConnection connection, UserBitShared.QueryId queryId, UserProtos.RunQuery queryRequest)	Constructor.

Method Summary

Modifier and Type	Method	Description
void	addToEventQueue(UserBitShared.QueryResult.QueryState state, Exception exception)	Adds query status in the event queue to process it when foreman is ready.
void	cancel()	Cancel the query (move query in cancellation requested state).
QueryContext	getQueryContext()	Get the QueryContext created for the query.
UserBitShared.QueryId	getQueryId()
QueryManager	getQueryManager()	Get the QueryManager created for the query.
String	getQueryText()
RuntimeFilterRouter	getRuntimeFilterRouter()
UserBitShared.QueryResult.QueryState	getState()
void	resume()	Resume the query.
void	run()	Called by execution pool to do query setup, and kick off remote execution.
void	startProcessingEvents()	While one fragments where sanding out, other might have been completed.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Foreman

public Foreman(WorkManager.WorkerBee bee,
 DrillbitContext drillbitContext,
 UserClientConnection connection,
 UserBitShared.QueryId queryId,
 UserProtos.RunQuery queryRequest)

Constructor. Sets up the Foreman, but does not initiate any execution.

Parameters:

bee - work manager (runs fragments)

drillbitContext - drillbit context

connection - connection

queryId - the id for the query

queryRequest - the query to execute

Method Details

getQueryId

public UserBitShared.QueryId getQueryId()

Returns:

query id

getState

public UserBitShared.QueryResult.QueryState getState()

Returns:

current query state

getQueryText

public String getQueryText()

Returns:

sql query text of the query request

getQueryContext

public QueryContext getQueryContext()

Get the QueryContext created for the query.

Returns:

the QueryContext

getQueryManager

public QueryManager getQueryManager()

Get the QueryManager created for the query.

Returns:

the QueryManager

cancel

public void cancel()

Cancel the query (move query in cancellation requested state). Query execution will be canceled once possible.

addToEventQueue

public void addToEventQueue(UserBitShared.QueryResult.QueryState state,
 Exception exception)

Adds query status in the event queue to process it when foreman is ready.

Parameters:

state - new query state

exception - exception if failure has occurred

resume

public void resume()

Resume the query. Regardless of the current state, this method sends a resume signal to all fragments. This method can be called multiple times.

run

public void run()

Called by execution pool to do query setup, and kick off remote execution.

Note that completion of this function is not the end of the Foreman's role in the query's lifecycle.

Specified by:

run in interface Runnable

startProcessingEvents

public void startProcessingEvents()

While one fragments where sanding out, other might have been completed. We don't want to process completed / failed events until all fragments are sent out. This method triggers events processing when all fragments were sent out.

getRuntimeFilterRouter

public RuntimeFilterRouter getRuntimeFilterRouter()