package org.apache.lucene.benchmark.byTask.tasks;
/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.
*/
import java.util.Random;
import org.apache.lucene.benchmark.byTask.PerfRunData;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.TermDocs;
/**
* Deletes a percentage of documents from an index randomly
* over the number of documents. The parameter, X, is in
* percent. EG 50 means 1/2 of all documents will be
* deleted.
*
* <p><b>NOTE</b>: the param is an absolute percentage of
* maxDoc(). This means if you delete 50%, and then delete
* 50% again, the 2nd delete will do nothing.
*
* <p> Parameters:
* <ul>
* <li> delete.percent.rand.seed - defines the seed to
* initialize Random (default 1717)
* </ul>
*/
public class DeleteByPercentTask extends PerfTask {
double percent;
int numDeleted = 0;
final Random random;
public DeleteByPercentTask(PerfRunData runData) {
super(runData);
random = new Random(runData.getConfig().get("delete.percent.rand.seed", 1717));
}
@Override
public void setup() throws Exception {
super.setup();
}
@Override
public void setParams(String params) {
super.setParams(params);
percent = Double.parseDouble(params)/100;
}
@Override
public boolean supportsParams() {
return true;
}
@Override
public int doLogic() throws Exception {
IndexReader r = getRunData().getIndexReader();
int maxDoc = r.maxDoc();
int numDeleted = 0;
// percent is an absolute target:
int numToDelete = ((int) (maxDoc * percent)) - r.numDeletedDocs();
if (numToDelete < 0) {
r.undeleteAll();
numToDelete = (int) (maxDoc * percent);
}
while (numDeleted < numToDelete) {
double delRate = ((double) (numToDelete-numDeleted))/r.numDocs();
TermDocs termDocs = r.termDocs(null);
while (termDocs.next() && numDeleted < numToDelete) {
if (random.nextDouble() <= delRate) {
r.deleteDocument(termDocs.doc());
numDeleted++;
}
}
termDocs.close();
}
System.out.println("--> processed (delete) " + numDeleted + " docs");
r.decRef();
return numDeleted;
}
}