/// <summary>
/// Called by the appender that just appended a transaction to the log.
/// </summary>
/// <param name="logForceEvents"> A trace event for the given log append operation. </param>
/// <returns> {@code true} if we got lucky and were the ones forcing the log. </returns>
//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in C#:
//ORIGINAL LINE: protected boolean forceAfterAppend(org.neo4j.kernel.impl.transaction.tracing.LogForceEvents logForceEvents) throws java.io.IOException
protected internal virtual bool ForceAfterAppend(LogForceEvents logForceEvents)
{
// There's a benign race here, where we add our link before we update our next pointer.
// This is okay, however, because unparkAll() spins when it sees a null next pointer.
ThreadLink threadLink = new ThreadLink(Thread.CurrentThread);
threadLink.Next = _threadLinkHead.getAndSet(threadLink);
bool attemptedForce = false;
using (LogForceWaitEvent logForceWaitEvent = logForceEvents.BeginLogForceWait())
{
do
{
if (_forceLock.tryLock())
{
attemptedForce = true;
try
{
ForceLog(logForceEvents);
// In the event of any failure a database panic will be raised and thrown here
}
finally
{
_forceLock.unlock();
// We've released the lock, so unpark anyone who might have decided park while we were working.
// The most recently parked thread is the one most likely to still have warm caches, so that's
// the one we would prefer to unpark. Luckily, the stack nature of the ThreadLinks makes it easy
// to get to.
ThreadLink nextWaiter = _threadLinkHead.get();
nextWaiter.Unpark();
}
}
else
{
WaitForLogForce();
}
} while (!threadLink.Done);
// If there were many threads committing simultaneously and I wasn't the lucky one
// actually doing the forcing (where failure would throw panic exception) I need to
// explicitly check if everything is OK before considering this transaction committed.
if (!attemptedForce)
{
_databaseHealth.assertHealthy(typeof(IOException));
}
}
return(attemptedForce);
}
private void UnparkAll(ThreadLink links)
{
do
{
links.Done = true;
links.Unpark();
ThreadLink tmp;
do
{
// Spin because of the race:y update when consing.
tmp = links.Next;
} while (tmp == null);
links = tmp;
} while (links != ThreadLink.End);
}
//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in C#:
//ORIGINAL LINE: private void forceLog(org.neo4j.kernel.impl.transaction.tracing.LogForceEvents logForceEvents) throws java.io.IOException
private void ForceLog(LogForceEvents logForceEvents)
{
ThreadLink links = _threadLinkHead.getAndSet(ThreadLink.End);
try
{
using (LogForceEvent logForceEvent = logForceEvents.BeginLogForce())
{
Force();
}
}
//JAVA TO C# CONVERTER WARNING: 'final' catch parameters are not available in C#:
//ORIGINAL LINE: catch (final Throwable panic)
catch (Exception panic)
{
_databaseHealth.panic(panic);
throw panic;
}
finally
{
UnparkAll(links);
}
}
