| /** |
| * |
| * 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.bookkeeper.common.util.affinity.impl; |
| |
| import static com.google.common.base.Preconditions.checkArgument; |
| |
| import java.io.IOException; |
| import java.nio.charset.Charset; |
| import java.nio.charset.StandardCharsets; |
| import java.nio.file.Files; |
| import java.nio.file.Paths; |
| import java.util.Map; |
| import java.util.Set; |
| import java.util.TreeMap; |
| import java.util.TreeSet; |
| |
| import org.apache.commons.lang3.StringUtils; |
| |
| /** |
| * Discover the list of processors from /proc/cpuinfo. |
| */ |
| class ProcessorsInfo { |
| |
| private static final Charset ENCODING = StandardCharsets.US_ASCII; |
| |
| /** |
| * Given one cpu id, return all CPUs that are sharing the same core. |
| */ |
| public Set<Integer> getCpusOnSameCore(int targetCpu) { |
| Set<Integer> result = new TreeSet<>(); |
| int targetCore = cpus.get(targetCpu); |
| |
| cpus.forEach((cpu, core) -> { |
| if (core == targetCore) { |
| result.add(cpu); |
| } |
| }); |
| |
| return result; |
| } |
| |
| private final Map<Integer, Integer> cpus = new TreeMap<>(); |
| |
| static ProcessorsInfo parseCpuInfo(String cpuInfoString) { |
| ProcessorsInfo pi = new ProcessorsInfo(); |
| |
| for (String cpu : cpuInfoString.split("\n\n")) { |
| int cpuId = -1; |
| int coreId = -1; |
| |
| for (String line : cpu.split("\n")) { |
| String[] parts = line.split(":", 2); |
| String key = StringUtils.trim(parts[0]); |
| String value = StringUtils.trim(parts[1]); |
| |
| if (key.equals("core id")) { |
| coreId = Integer.parseInt(value); |
| } else if (key.equals("processor")) { |
| cpuId = Integer.parseInt(value); |
| } else { |
| // ignore |
| } |
| } |
| |
| checkArgument(cpuId >= 0); |
| checkArgument(coreId >= 0); |
| pi.cpus.put(cpuId, coreId); |
| } |
| |
| return pi; |
| } |
| |
| static ProcessorsInfo parseCpuInfo() { |
| try { |
| return parseCpuInfo(new String(Files.readAllBytes(Paths.get("/proc/cpuinfo")), ENCODING)); |
| } catch (IOException e) { |
| throw new RuntimeException(e); |
| } |
| } |
| } |