OOMHandler.java
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freenet.support |
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Freenet |
View: Reasons, Metrics, Source Code
These are the metrics that contribute to the Enerjy Score for this file, ranked by impact. So the metrics listed at the top influence the score to a greater extent that the metrics listed at the bottom.
| Metric | Description | |
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/* This code is part of Freenet. It is distributed under the GNU General
* Public License, version 2 (or at your option any later version). See
* http://www.gnu.org/ for further details of the GPL. */
package freenet.support;
import java.util.Iterator;
import java.util.Set;
import org.tanukisoftware.wrapper.WrapperManager;
/**
* Do this processing as a standard response to an OutOfMemoryError
*/
public class OOMHandler {
private static volatile boolean isOOM = false;
/**
* Emergency memory, freed when OOM occur. Marked <code>volatile</code> to make sure gc thread
* see it's free'd.
*/
private static volatile byte[] emergencyPool = new byte[8192];
/**
* List of {@link OOMHook}s
*/
private static Set<OOMHook> oomHooks = new WeakHashSet<OOMHook>();
public static void addOOMHook(OOMHook hook) {
synchronized (oomHooks) {
oomHooks.add(hook);
}
}
/**
* Call this when running low of memory
*/
public static void lowMemory() {
System.gc();
System.runFinalization();
// iterate all oom hooks
Iterator<OOMHook> it = oomHooks.iterator();
while (it.hasNext()) {
OOMHook hook = it.next();
if (hook != null) {
try {
hook.handleLowMemory();
} catch (Throwable t) {
//ignore
}
}
}
System.gc();
System.runFinalization();
}
public static void handleOOM(OutOfMemoryError e) {
if (isOOM) {
Logger.error(null, "Double OOM", e);
return;
}
isOOM = true;
Runtime r = null;
try {
r = Runtime.getRuntime();
long usedAtStart = r.totalMemory() - r.freeMemory();
if (emergencyPool != null)
emergencyPool = null;
System.gc();
System.runFinalization();
// iterate all oom hooks
Iterator<OOMHook> it = oomHooks.iterator();
while (it.hasNext()) {
OOMHook hook = it.next();
if (hook != null) {
try {
hook.handleOutOfMemory();
} catch (Throwable t) {
//ignore
}
}
}
System.gc();
System.runFinalization();
System.err.println(e.getClass());
System.err.println(e.getMessage());
e.printStackTrace();
if(e.getMessage().equals("Java heap space")) {
Thread.dumpStack();
}
long usedNow = r.totalMemory() - r.freeMemory();
System.err.println("Memory: GC "+SizeUtil.formatSize(usedAtStart, false)+" -> "+SizeUtil.formatSize(usedNow, false)+": total "+SizeUtil.formatSize(r.totalMemory(), false)+" free "+SizeUtil.formatSize(r.freeMemory(), false)+" max "+SizeUtil.formatSize(r.maxMemory(), false));
ThreadGroup tg = Thread.currentThread().getThreadGroup();
while(tg.getParent() != null) tg = tg.getParent();
System.err.println("Running threads: "+tg.activeCount());
// Logger after everything else since it might throw
Logger.error(null, "Caught "+e, e);
Logger.error(null, "Memory: GC "+SizeUtil.formatSize(usedAtStart, false)+" -> "+SizeUtil.formatSize(usedNow, false)+": total "+SizeUtil.formatSize(r.totalMemory(), false)+" free "+SizeUtil.formatSize(r.freeMemory(), false)+" max "+SizeUtil.formatSize(r.maxMemory(), false));
Logger.error(null, "Running threads: "+tg.activeCount());
} catch (Throwable t) {
// Try without GCing, it might be a thread error; GCing creates a thread
System.err.println("Caught handling OOM "+e+" : "+t);
e.printStackTrace();
if(r != null)
System.err.println("Memory: total "+SizeUtil.formatSize(r.totalMemory(), false)+" free "+SizeUtil.formatSize(r.freeMemory(), false)+" max "+SizeUtil.formatSize(r.maxMemory(), false));
ThreadGroup tg = Thread.currentThread().getThreadGroup();
while(tg.getParent() != null) tg = tg.getParent();
System.err.println("Running threads: "+tg.activeCount());
WrapperManager.requestThreadDump(); // Will probably crash, but never mind...
} finally {
isOOM = false;
}
}
}
The table below shows all metrics for OOMHandler.java.
| Metric | Value | Description | |
|---|---|---|---|