/*
* Copyright (c) 2009, 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
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.sun.max.util;
import java.io.*;
import java.util.regex.*;
/**
* Class for run-time system information.
*/
public final class RuntimeInfo {
/**
* Gets the suggested maximum number of processes to fork.
* @param requestedMemorySize the physical memory size (in bytes) that each process will consume.
* @return the suggested number of processes that should be started in parallel.
*/
public static int getSuggestedMaximumProcesses(long requestedMemorySize) {
final Runtime runtime = Runtime.getRuntime();
final String os = System.getProperty("os.name");
long freeMemory = 0L;
try {
if (os.equals("Linux")) {
final Process process = runtime.exec(new String[] {"/usr/bin/free", "-ob"});
final BufferedReader in = new BufferedReader(new InputStreamReader(process.getInputStream()));
in.readLine();
final String line = in.readLine();
final String[] fields = line.split("\\s+");
freeMemory = Long.parseLong(fields[3]);
} else if (os.equals("SunOS")) {
Process process = runtime.exec(new String[] {"/bin/kstat", "-p", "-nsystem_pages", "-sfreemem"});
BufferedReader in = new BufferedReader(new InputStreamReader(process.getInputStream()));
String line = in.readLine();
String[] fields = line.split("\\s+");
freeMemory = Long.parseLong(fields[1]);
process = runtime.exec(new String[] {"/bin/getconf", "PAGESIZE"});
in = new BufferedReader(new InputStreamReader(process.getInputStream()));
line = in.readLine();
freeMemory *= Long.parseLong(line);
} else if (os.equals("Mac OS X") || os.equals("Darwin")) {
final Process process = runtime.exec("/usr/bin/vm_stat");
final BufferedReader in = new BufferedReader(new InputStreamReader(process.getInputStream()));
final Matcher matcher = Pattern.compile("[^0-9]*([0-9]+)[^0-9]*").matcher(in.readLine());
if (matcher.matches()) {
freeMemory = Long.parseLong(matcher.group(1));
}
matcher.reset(in.readLine());
if (matcher.matches()) {
freeMemory *= Long.parseLong(matcher.group(1));
}
} else if (os.equals("MaxVE")) {
freeMemory = 0L;
}
} catch (Exception e) {
freeMemory = 0L;
}
final int processors = runtime.availableProcessors();
if (freeMemory <= 0L || freeMemory >= requestedMemorySize * processors) {
return processors;
}
return Math.max(1, (int) (freeMemory / requestedMemorySize));
}
private RuntimeInfo() {
}
}