| /** |
| * 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.tajo.pullserver; |
| |
| import org.apache.commons.lang.reflect.MethodUtils; |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.io.nativeio.NativeIO; |
| |
| import java.io.FileDescriptor; |
| import java.lang.reflect.Method; |
| |
| public class PullServerUtil { |
| private static final Log LOG = LogFactory.getLog(PullServerUtil.class); |
| |
| private static boolean nativeIOPossible = false; |
| private static Method posixFadviseIfPossible; |
| |
| static { |
| if (NativeIO.isAvailable() && loadNativeIO()) { |
| nativeIOPossible = true; |
| } else { |
| LOG.warn("Unable to load hadoop nativeIO"); |
| } |
| } |
| |
| public static boolean isNativeIOPossible() { |
| return nativeIOPossible; |
| } |
| |
| /** |
| * Call posix_fadvise on the given file descriptor. See the manpage |
| * for this syscall for more information. On systems where this |
| * call is not available, does nothing. |
| */ |
| public static void posixFadviseIfPossible(String identifier, java.io.FileDescriptor fd, |
| long offset, long len, int flags) { |
| if (nativeIOPossible) { |
| try { |
| posixFadviseIfPossible.invoke(null, identifier, fd, offset, len, flags); |
| } catch (Throwable t) { |
| nativeIOPossible = false; |
| LOG.warn("Failed to manage OS cache for " + identifier, t); |
| } |
| } |
| } |
| |
| /* load hadoop native method if possible */ |
| private static boolean loadNativeIO() { |
| boolean loaded = true; |
| if (nativeIOPossible) return loaded; |
| |
| Class[] parameters = {String.class, FileDescriptor.class, Long.TYPE, Long.TYPE, Integer.TYPE}; |
| try { |
| Method getCacheManipulator = MethodUtils.getAccessibleMethod(NativeIO.POSIX.class, "getCacheManipulator", new Class[0]); |
| Class posixClass; |
| if (getCacheManipulator != null) { |
| Object posix = MethodUtils.invokeStaticMethod(NativeIO.POSIX.class, "getCacheManipulator", null); |
| posixClass = posix.getClass(); |
| } else { |
| posixClass = NativeIO.POSIX.class; |
| } |
| posixFadviseIfPossible = MethodUtils.getAccessibleMethod(posixClass, "posixFadviseIfPossible", parameters); |
| } catch (Throwable e) { |
| loaded = false; |
| LOG.warn("Failed to access posixFadviseIfPossible :" + e.getMessage(), e); |
| } |
| |
| if (posixFadviseIfPossible == null) { |
| loaded = false; |
| } |
| return loaded; |
| } |
| } |