hotspot/src/os/linux/vm/globals_linux.hpp
author iveresov
Fri, 29 Apr 2011 12:39:32 -0700
changeset 9419 f0360dfe734d
parent 9335 7bdd2a3ab3d8
child 15926 8e87d545195f
permissions -rw-r--r--
7040485: Use transparent huge page on linux by default Summary: Turn on UseLargePages by default but try only HugeTLBFS method if it is not explicitly specified on the command line. Reviewed-by: ysr

/*
 * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * questions.
 *
 */

#ifndef OS_LINUX_VM_GLOBALS_LINUX_HPP
#define OS_LINUX_VM_GLOBALS_LINUX_HPP

//
// Defines Linux specific flags. They are not available on other platforms.
//
#define RUNTIME_OS_FLAGS(develop, develop_pd, product, product_pd, diagnostic, notproduct) \
  product(bool, UseOprofile, false,                                     \
        "enable support for Oprofile profiler")                         \
                                                                        \
  product(bool, UseLinuxPosixThreadCPUClocks, true,                     \
          "enable fast Linux Posix clocks where available")             \
/*  NB: The default value of UseLinuxPosixThreadCPUClocks may be        \
    overridden in Arguments::parse_each_vm_init_arg.  */                \
                                                                        \
  product(bool, UseHugeTLBFS, false,                                    \
          "Use MAP_HUGETLB for large pages")                            \
                                                                        \
  product(bool, UseSHM, false,                                          \
          "Use SYSV shared memory for large pages")

//
// Defines Linux-specific default values. The flags are available on all
// platforms, but they may have different default values on other platforms.
//
define_pd_global(bool, UseLargePages, true);
define_pd_global(bool, UseLargePagesIndividualAllocation, false);
define_pd_global(bool, UseOSErrorReporting, false);
define_pd_global(bool, UseThreadPriorities, true) ;

#endif // OS_LINUX_VM_GLOBALS_LINUX_HPP