view src/share/vm/runtime/jniPeriodicChecker.cpp @ 1145:e018e6884bd8

6631166: CMS: better heuristics when combatting fragmentation Summary: Autonomic per-worker free block cache sizing, tunable coalition policies, fixes to per-size block statistics, retuned gain and bandwidth of some feedback loop filters to allow quicker reactivity to abrupt changes in ambient demand, and other heuristics to reduce fragmentation of the CMS old gen. Also tightened some assertions, including those related to locking. Reviewed-by: jmasa
author ysr
date Wed, 23 Dec 2009 09:23:54 -0800
parents a61af66fc99e
children c18cbe5936b8
line wrap: on
line source

/*
 * Copyright 2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

# include "incls/_precompiled.incl"
# include "incls/_jniPeriodicChecker.cpp.incl"


// --------------------------------------------------------
// Class to aid in periodic checking under CheckJNICalls
class JniPeriodicCheckerTask : public PeriodicTask {
  public:
     JniPeriodicCheckerTask(int interval_time) : PeriodicTask(interval_time) {}
     void task() { os::run_periodic_checks(); }
     static void engage();
     static void disengage();
};


//----------------------------------------------------------
// Implementation of JniPeriodicChecker

JniPeriodicCheckerTask*              JniPeriodicChecker::_task   = NULL;

/*
 * The engage() method is called at initialization time via
 * Thread::create_vm() to initialize the JniPeriodicChecker and
 * register it with the WatcherThread as a periodic task.
 */
void JniPeriodicChecker::engage() {
  if (CheckJNICalls && !is_active()) {
    // start up the periodic task
    _task = new JniPeriodicCheckerTask(10);
    _task->enroll();
  }
}


/*
 * the disengage() method is responsible for deactivating the periodic
 * task. This  method is called from before_exit() in java.cpp and is only called
 * after the WatcherThread has been stopped.
 */
void JniPeriodicChecker::disengage() {
  if (CheckJNICalls && is_active()) {
    // remove JniPeriodicChecker
    _task->disenroll();
    delete _task;
    _task = NULL;
  }
}

void jniPeriodicChecker_exit() {
  if (!CheckJNICalls) return;
}