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ASF GitHub Bot commented on ACCUMULO-4187: ------------------------------------------ Github user ShawnWalker commented on a diff in the pull request: https://github.com/apache/accumulo/pull/90#discussion_r59563956 --- Diff: core/src/main/java/org/apache/accumulo/core/file/streams/PositionedOutputs.java --- @@ -0,0 +1,55 @@ +/* + * 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. + */ +package org.apache.accumulo.core.file.streams; + +import java.io.FilterOutputStream; +import java.io.IOException; +import java.io.OutputStream; +import org.apache.hadoop.fs.FSDataOutputStream; + +public class PositionedOutputs { + public static PositionedOutputStream wrap(final OutputStream fout) { + if (fout instanceof FSDataOutputStream) { + return new PositionedOutputStream(fout) { + @Override + public long position() throws IOException { + return ((FSDataOutputStream) fout).getPos(); + } + }; + } else if (fout instanceof PositionedOutput) { + return new PositionedOutputStream(fout) { + @Override + public long position() throws IOException { + return ((PositionedOutput) fout).position(); + } + }; + } else { + return new PositionedOutputStream(fout) { + @Override + public long position() throws IOException { + throw new UnsupportedOperationException("Underlying stream does not support position()"); + } + }; + } + } + + public static abstract class PositionedOutputStream extends FilterOutputStream implements PositionedOutput { --- End diff -- I don't believe it is, in fact. > Rate limiting of major compactions > ---------------------------------- > > Key: ACCUMULO-4187 > URL: https://issues.apache.org/jira/browse/ACCUMULO-4187 > Project: Accumulo > Issue Type: Improvement > Components: core, tserver > Affects Versions: 1.8.0 > Reporter: Shawn Walker > Assignee: Shawn Walker > Priority: Minor > Fix For: 1.8.0 > > > In discussing [ACCUMULO-4166] with Keith Turner, we decided that the > underlying issue is that major compactions can overwhelm a tablet server, > rendering it nearly unresponsive. > To address this, we should take a cue from Apache Cassandra and restrict how > quickly we perform major compactions. Rate limiting reads and writes > involved in major compactions will directly affect the IO load caused by > major compactions, and should also indirectly affect the CPU load. -- This message was sent by Atlassian JIRA (v6.3.4#6332)