/**
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Created on Nov 27, 2011
*/
package com.bigdata.rdf.sparql.ast.hints;
import com.bigdata.bop.BufferAnnotations;
import com.bigdata.rdf.sparql.ast.QueryHints;
/**
* This is identical to the {@link BufferChunkCapacityHint}, but it is accessed
* through the well known name {@link QueryHints#CHUNK_SIZE}.
* <p>
* Sets the capacity of the output buffer that used to accumulate chunks of
* solutions (default {@value BufferAnnotations#DEFAULT_CHUNK_CAPACITY}).
* Partial chunks may be automatically combined into full chunks.
* <p>
* Note: The "chunkSize" is a general property of the query engine. This query
* hint does not change the structure of the query plan, but simply serves as a
* directive to the query engine that it should allocate an output buffer for
* the operator that will emit chunks of the indicated target capacity. This
* query hint is allowed in any scope, but is generally used to effect the
* behavior of a join group, a subquery, or the entire query. The hint is
* transferred as an annotation onto all query plan operators generated from the
* annotated scope.
*
* @see BufferAnnotations#CHUNK_CAPACITY
*/
final class ChunkSizeHint extends AbstractChunkSizeHint {
protected ChunkSizeHint() {
super(QueryHints.CHUNK_SIZE,
BufferAnnotations.DEFAULT_CHUNK_CAPACITY);
}
}