edu.usc.goffish.gofs.util.partitioning.metis.MetisPartitioner.java Source code

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Here is the source code for edu.usc.goffish.gofs.util.partitioning.metis.MetisPartitioner.java

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/*
*    Copyright 2013 University of Southern California
*
*  Licensed 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 edu.usc.goffish.gofs.util.partitioning.metis;

import java.io.*;
import java.nio.file.*;

import org.apache.commons.io.*;

import edu.usc.goffish.gofs.formats.metis.*;
import edu.usc.goffish.gofs.graph.*;
import edu.usc.goffish.gofs.util.*;
import edu.usc.goffish.gofs.util.partitioning.*;

public class MetisPartitioner implements IPartitioner {

    private static final Path DefaultMetisBinary = Paths.get("gpmetis");
    private static final Path DefaultMetisInput = Paths.get("input.metis");

    private final Path _metisBinaryPath;
    private final String[] _extraMetisOptions;

    public MetisPartitioner() {
        this(DefaultMetisBinary, null);
    }

    public MetisPartitioner(Path metisBinaryPath, String[] extraMetisOptions) {
        if (metisBinaryPath == null) {
            throw new IllegalArgumentException();
        }

        _metisBinaryPath = metisBinaryPath.normalize();
        _extraMetisOptions = extraMetisOptions;
    }

    @Override
    public IPartitioning partition(IIdentifiableVertexGraph<? extends IIdentifiableVertex, ? extends IEdge> graph,
            int numPartitions) throws IOException {
        if (graph == null) {
            throw new IllegalArgumentException();
        }
        if (numPartitions < 1) {
            throw new IllegalArgumentException();
        }
        if (graph.isDirected()) {
            throw new IllegalArgumentException();
        }

        Path workingDir = Files.createTempDirectory("gofs_metis");
        try {
            // we assume the graph will always require renumbering
            System.out.print("writing metis input file (with renumbering)... ");
            long time = System.currentTimeMillis();

            // write metis input
            Path metisInputPath = workingDir.resolve(DefaultMetisInput);
            long[] renumbering = MetisGraph.writeAndRenumber(graph, Files.newOutputStream(metisInputPath));

            System.out.println("[" + (System.currentTimeMillis() - time) + "ms]");

            // perform partitioning
            Path metisOutputPath = partition(workingDir, metisInputPath, numPartitions);

            System.out.print("loading metis output... ");
            time = System.currentTimeMillis();

            // read metis output
            IPartitioning partitioning = MetisPartitioning.readAndRenumber(Files.newInputStream(metisOutputPath),
                    renumbering);

            System.out.println("[" + (System.currentTimeMillis() - time) + "ms]");

            return partitioning;
        } finally {
            FileUtils.deleteQuietly(workingDir.toFile());
        }
    }

    public IPartitioning partition(Path metisInputPath, int numPartitions) throws IOException {
        if (metisInputPath == null) {
            throw new IllegalArgumentException();
        }
        if (numPartitions < 1) {
            throw new IllegalArgumentException();
        }

        Path workingDir = Files.createTempDirectory("working");
        try {
            // perform partitioning
            Path metisOutputPath = partition(workingDir, metisInputPath, numPartitions);

            System.out.print("loading metis output... ");
            long time = System.currentTimeMillis();

            // read metis output
            IPartitioning partitioning = MetisPartitioning.read(Files.newInputStream(metisOutputPath));

            System.out.println("[" + (System.currentTimeMillis() - time) + "ms]");

            return partitioning;
        } finally {
            FileUtils.deleteQuietly(workingDir.toFile());
        }
    }

    private Path partition(Path workingDir, Path metisInputPath, int numPartitions) throws IOException {

        // prepare metis command
        ProcessHelper.CommandBuilder command = new ProcessHelper.CommandBuilder(_metisBinaryPath.toString());
        if (_extraMetisOptions != null) {
            command.append(_extraMetisOptions);
        }
        command.append(metisInputPath).append(Integer.toString(numPartitions));

        // run metis
        try {
            System.out.println("executing: \"" + command + "\"");
            ProcessHelper.runProcess(workingDir.toFile(), true, command.toArray());
        } catch (InterruptedException e) {
            throw new IOException(e);
        }

        return workingDir.resolve(metisInputPath.getFileName() + ".part." + numPartitions);
    }
}