io.druid.query.search.ConciseBitmapDecisionHelper Maven / Gradle / Ivy
/*
* Licensed to Metamarkets Group Inc. (Metamarkets) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Metamarkets licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package io.druid.query.search;
public class ConciseBitmapDecisionHelper extends SearchQueryDecisionHelper
{
// This value comes from an experiment.
// See the discussion at https://github.com/druid-io/druid/pull/3792#issuecomment-268331804.
private static final double BITMAP_INTERSECT_COST = 7.425;
private static final ConciseBitmapDecisionHelper INSTANCE = new ConciseBitmapDecisionHelper();
public static ConciseBitmapDecisionHelper instance()
{
return INSTANCE;
}
private ConciseBitmapDecisionHelper()
{
super(BITMAP_INTERSECT_COST);
}
}