Package org.apache.solr.search

Class TimeAllowedLimit

java.lang.Object

org.apache.solr.search.TimeAllowedLimit

All Implemented Interfaces:

org.apache.lucene.index.QueryTimeout, QueryLimit

public class TimeAllowedLimit
extends Object
implements QueryLimit

Enforces a wall clock based timeout on a given SolrQueryRequest. This class holds the logic for the timeAllowed query parameter. Note that timeAllowed will be ignored for local processing of sub-queries in cases where the parent query already has timeAllowed set. Essentially only one timeAllowed can be specified for any thread executing a query. This is to ensure that subqueries don't escape from the intended limit.

Distributed requests will approximately track the original starting point of the parent request. Shard requests may be skipped if the limit would run out shortly after they are sent - this in-flight allowance is determined by INFLIGHT_PARAM in milliseconds, with the default value of DEFAULT_INFLIGHT_MS.

Field Summary

Fields

Modifier and Type	Field	Description
static final long	DEFAULT_INFLIGHT_MS	Arbitrary small amount of time to account for network flight time in ms
static final String	INFLIGHT_PARAM
static final String	USED_PARAM

Constructor Summary

Constructors

Constructor	Description
TimeAllowedLimit(SolrQueryRequest req)	Create an object to represent a time limit for the current request.

Method Summary

Modifier and Type	Method	Description
boolean	adjustShardRequestLimit(ShardRequest sreq, String shard, org.apache.solr.common.params.ModifiableSolrParams params)	Allow limit to adjust shard request parameters if needed.
Object	currentValue()	Return elapsed time in nanoseconds since this limit was started.
boolean	shouldExit()	Return true if a max limit value is set and the current usage has exceeded the limit.

Methods inherited from class java.lang.Object

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

Field Details

USED_PARAM

public static final String USED_PARAM

See Also:

• Constant Field Values

INFLIGHT_PARAM

public static final String INFLIGHT_PARAM

See Also:

• Constant Field Values

DEFAULT_INFLIGHT_MS

public static final long DEFAULT_INFLIGHT_MS

Arbitrary small amount of time to account for network flight time in ms

See Also:

• Constant Field Values

Constructor Details

TimeAllowedLimit

public TimeAllowedLimit(SolrQueryRequest req)

Create an object to represent a time limit for the current request.

Parameters:

req - A solr request that has a value for timeAllowed

Throws:

IllegalArgumentException - if the request does not contain timeAllowed parameter. This should be validated with hasTimeLimit(SolrQueryRequest) prior to constructing this object

Method Details

adjustShardRequestLimit

public boolean adjustShardRequestLimit(ShardRequest sreq,
 String shard,
 org.apache.solr.common.params.ModifiableSolrParams params)

Description copied from interface: QueryLimit

Allow limit to adjust shard request parameters if needed.

Specified by:

adjustShardRequestLimit in interface QueryLimit

Returns:

true if the shard request should be skipped because a limit will be tripped after sending, during execution.

shouldExit

public boolean shouldExit()

Return true if a max limit value is set and the current usage has exceeded the limit.

Specified by:

shouldExit in interface org.apache.lucene.index.QueryTimeout

currentValue

public Object currentValue()

Return elapsed time in nanoseconds since this limit was started.

Specified by:

currentValue in interface QueryLimit

Returns:

an expression of the amount of the limit used so far, numeric if possible, if non-numeric it should have toString() suitable for logging or similar expression to the user.