accumulo-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From joshelser <...@git.apache.org>
Subject [GitHub] accumulo pull request: ACCUMULO-3602 BatchScanner optimization for...
Date Thu, 02 Apr 2015 02:48:24 GMT
Github user joshelser commented on a diff in the pull request:

    https://github.com/apache/accumulo/pull/25#discussion_r27629523
  
    --- Diff: core/src/main/java/org/apache/accumulo/core/client/mapreduce/BatchInputSplit.java
---
    @@ -0,0 +1,151 @@
    +/*
    + * 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.client.mapreduce;
    +
    +import java.io.DataInput;
    +import java.io.DataOutput;
    +import java.io.IOException;
    +import java.util.ArrayList;
    +import java.util.Arrays;
    +import java.util.Collection;
    +import java.util.Collections;
    +
    +import org.apache.accumulo.core.data.Key;
    +import org.apache.accumulo.core.data.PartialKey;
    +import org.apache.accumulo.core.data.Range;
    +
    +/**
    + * The Class BatchInputSplit. Encapsulates a set of Accumulo ranges on a single tablet
for use in Map Reduce jobs.
    + * Can contain several Ranges per split.
    + */
    +public class BatchInputSplit extends AccumuloInputSplit {
    +  private Collection<Range> ranges;
    +  private int scanThreads;
    +
    +  public BatchInputSplit() {
    +    ranges = Collections.emptyList();
    +  }
    +
    +  public BatchInputSplit(BatchInputSplit split) throws IOException {
    +    super(split);
    +    this.setRanges(split.getRanges());
    +  }
    +
    +  protected BatchInputSplit(String table, String tableId, Collection<Range> ranges,
String[] locations) {
    +    super(table, tableId, locations);
    +    this.ranges = ranges;
    +  }
    +
    +  public float getProgress(Key currentKey) {
    +    if (currentKey == null)
    +      return 0f;
    +    for (Range range : ranges) {
    --- End diff --
    
    Sadly, this isn't really representative like it was for a single Range per InputSplit.
There will be a semblance of ordering (as Accumulo is going to be doing batches under the
hood), but there's no real progress you can identify out of keys from a BatchScanner. The
only realistic approximation I can think of is based off of some stats we store in the metadata
table, but I don't think that's realistic in this changeset.
    I can't think of a reliable way to do this computation. If that's the case, I'd be apt
to just `return 0` and mark it as a TODO


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastructure@apache.org or file a JIRA ticket
with INFRA.
---

Mime
View raw message