/* * 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.cassandra.utils; import java.io.File; import java.io.FileDescriptor; import java.io.FileInputStream; import java.io.IOException; import java.lang.reflect.Field; import java.nio.channels.FileChannel; import java.nio.file.Paths; import java.nio.file.StandardOpenOption; import java.util.concurrent.TimeUnit; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.sun.jna.LastErrorException; import com.sun.jna.Native; import com.sun.jna.Pointer; public final class CLibrary { private static final Logger logger = LoggerFactory.getLogger(CLibrary.class); private static final int MCL_CURRENT; private static final int MCL_FUTURE; private static final int ENOMEM = 12; private static final int F_GETFL = 3; /* get file status flags */ private static final int F_SETFL = 4; /* set file status flags */ private static final int F_NOCACHE = 48; /* Mac OS X specific flag, turns cache on/off */ private static final int O_DIRECT = 040000; /* fcntl.h */ private static final int O_RDONLY = 00000000; /* fcntl.h */ private static final int POSIX_FADV_NORMAL = 0; /* fadvise.h */ private static final int POSIX_FADV_RANDOM = 1; /* fadvise.h */ private static final int POSIX_FADV_SEQUENTIAL = 2; /* fadvise.h */ private static final int POSIX_FADV_WILLNEED = 3; /* fadvise.h */ private static final int POSIX_FADV_DONTNEED = 4; /* fadvise.h */ private static final int POSIX_FADV_NOREUSE = 5; /* fadvise.h */ static boolean jnaAvailable = true; static boolean jnaLockable = false; static { try { Native.register("c"); } catch (NoClassDefFoundError e) { logger.warn("JNA not found. Native methods will be disabled."); jnaAvailable = false; } catch (UnsatisfiedLinkError e) { logger.warn("JNA link failure, one or more native method will be unavailable."); logger.trace("JNA link failure details: {}", e.getMessage()); } catch (NoSuchMethodError e) { logger.warn("Obsolete version of JNA present; unable to register C library. Upgrade to JNA 3.2.7 or later"); jnaAvailable = false; } if (System.getProperty("os.arch").toLowerCase().contains("ppc")) { if (System.getProperty("os.name").toLowerCase().contains("linux")) { MCL_CURRENT = 0x2000; MCL_FUTURE = 0x4000; } else if (System.getProperty("os.name").toLowerCase().contains("aix")) { MCL_CURRENT = 0x100; MCL_FUTURE = 0x200; } else { MCL_CURRENT = 1; MCL_FUTURE = 2; } } else { MCL_CURRENT = 1; MCL_FUTURE = 2; } } private static native int mlockall(int flags) throws LastErrorException; private static native int munlockall() throws LastErrorException; private static native int fcntl(int fd, int command, long flags) throws LastErrorException; private static native int posix_fadvise(int fd, long offset, int len, int flag) throws LastErrorException; private static native int open(String path, int flags) throws LastErrorException; private static native int fsync(int fd) throws LastErrorException; private static native int close(int fd) throws LastErrorException; private static native Pointer strerror(int errnum) throws LastErrorException; private static int errno(RuntimeException e) { assert e instanceof LastErrorException; try { return ((LastErrorException) e).getErrorCode(); } catch (NoSuchMethodError x) { logger.warn("Obsolete version of JNA present; unable to read errno. Upgrade to JNA 3.2.7 or later"); return 0; } } private CLibrary() {} public static boolean jnaAvailable() { return jnaAvailable; } public static boolean jnaMemoryLockable() { return jnaLockable; } public static void tryMlockall() { try { mlockall(MCL_CURRENT); jnaLockable = true; logger.info("JNA mlockall successful"); } catch (UnsatisfiedLinkError e) { // this will have already been logged by CLibrary, no need to repeat it } catch (RuntimeException e) { if (!(e instanceof LastErrorException)) throw e; if (errno(e) == ENOMEM && System.getProperty("os.name").toLowerCase().contains("linux")) { logger.warn("Unable to lock JVM memory (ENOMEM)." + " This can result in part of the JVM being swapped out, especially with mmapped I/O enabled." + " Increase RLIMIT_MEMLOCK or run Cassandra as root."); } else if (!System.getProperty("os.name").toLowerCase().contains("mac")) { // OS X allows mlockall to be called, but always returns an error logger.warn("Unknown mlockall error {}", errno(e)); } } } public static void trySkipCache(String path, long offset, long len) { File f = new File(path); if (!f.exists()) return; try (FileInputStream fis = new FileInputStream(f)) { trySkipCache(getfd(fis.getChannel()), offset, len, path); } catch (IOException e) { logger.warn("Could not skip cache", e); } } public static void trySkipCache(int fd, long offset, long len, String path) { if (len == 0) trySkipCache(fd, 0, 0, path); while (len > 0) { int sublen = (int) Math.min(Integer.MAX_VALUE, len); trySkipCache(fd, offset, sublen, path); len -= sublen; offset -= sublen; } } public static void trySkipCache(int fd, long offset, int len, String path) { if (fd < 0) return; try { if (System.getProperty("os.name").toLowerCase().contains("linux")) { int result = posix_fadvise(fd, offset, len, POSIX_FADV_DONTNEED); if (result != 0) NoSpamLogger.log( logger, NoSpamLogger.Level.WARN, 10, TimeUnit.MINUTES, "Failed trySkipCache on file: {} Error: " + strerror(result).getString(0), path); } } catch (UnsatisfiedLinkError e) { // if JNA is unavailable just skipping Direct I/O // instance of this class will act like normal RandomAccessFile } catch (RuntimeException e) { if (!(e instanceof LastErrorException)) throw e; logger.warn(String.format("posix_fadvise(%d, %d) failed, errno (%d).", fd, offset, errno(e))); } } public static int tryFcntl(int fd, int command, int flags) { // fcntl return value may or may not be useful, depending on the command int result = -1; try { result = fcntl(fd, command, flags); } catch (UnsatisfiedLinkError e) { // if JNA is unavailable just skipping } catch (RuntimeException e) { if (!(e instanceof LastErrorException)) throw e; logger.warn(String.format("fcntl(%d, %d, %d) failed, errno (%d).", fd, command, flags, errno(e))); } return result; } public static int tryOpenDirectory(String path) { int fd = -1; try { return open(path, O_RDONLY); } catch (UnsatisfiedLinkError e) { // JNA is unavailable just skipping Direct I/O } catch (RuntimeException e) { if (!(e instanceof LastErrorException)) throw e; logger.warn(String.format("open(%s, O_RDONLY) failed, errno (%d).", path, errno(e))); } return fd; } public static void trySync(int fd) { if (fd == -1) return; try { fsync(fd); } catch (UnsatisfiedLinkError e) { // JNA is unavailable just skipping Direct I/O } catch (RuntimeException e) { if (!(e instanceof LastErrorException)) throw e; logger.warn(String.format("fsync(%d) failed, errno (%d) {}", fd, errno(e)), e); } } public static void tryCloseFD(int fd) { if (fd == -1) return; try { close(fd); } catch (UnsatisfiedLinkError e) { // JNA is unavailable just skipping Direct I/O } catch (RuntimeException e) { if (!(e instanceof LastErrorException)) throw e; logger.warn(String.format("close(%d) failed, errno (%d).", fd, errno(e))); } } public static int getfd(FileChannel channel) { Field field = FBUtilities.getProtectedField(channel.getClass(), "fd"); try { return getfd((FileDescriptor)field.get(channel)); } catch (IllegalArgumentException|IllegalAccessException e) { logger.warn("Unable to read fd field from FileChannel"); } return -1; } /** * Get system file descriptor from FileDescriptor object. * @param descriptor - FileDescriptor objec to get fd from * @return file descriptor, -1 or error */ public static int getfd(FileDescriptor descriptor) { Field field = FBUtilities.getProtectedField(descriptor.getClass(), "fd"); try { return field.getInt(descriptor); } catch (Exception e) { JVMStabilityInspector.inspectThrowable(e); logger.warn("Unable to read fd field from FileDescriptor"); } return -1; } }