//JAVA TO C# CONVERTER TODO TASK: Most Java annotations will not have direct .NET equivalent attributes:
//ORIGINAL LINE: @Test void mustCountEvictions()
internal virtual void MustCountEvictions()
{
using (EvictionRunEvent evictionRunEvent = _tracer.beginPageEvictions(2))
{
using (EvictionEvent evictionEvent = evictionRunEvent.BeginEviction())
{
FlushEvent flushEvent = evictionEvent.FlushEventOpportunity().beginFlush(0, 0, _swapper);
flushEvent.AddBytesWritten(12);
flushEvent.Done();
}
using (EvictionEvent evictionEvent = evictionRunEvent.BeginEviction())
{
FlushEvent flushEvent = evictionEvent.FlushEventOpportunity().beginFlush(0, 0, _swapper);
flushEvent.AddBytesWritten(12);
flushEvent.Done();
evictionEvent.ThrewException(new IOException());
}
using (EvictionEvent evictionEvent = evictionRunEvent.BeginEviction())
{
FlushEvent flushEvent = evictionEvent.FlushEventOpportunity().beginFlush(0, 0, _swapper);
flushEvent.AddBytesWritten(12);
flushEvent.Done();
evictionEvent.ThrewException(new IOException());
}
evictionRunEvent.BeginEviction().close();
}
AssertCounts(0, 0, 0, 0, 4, 2, 3, 0, 36, 0, 0, 0d);
}
internal virtual void Vacuum(SwapperSet swappers)
{
if (FreelistHead is AtomicInteger && swappers.CountAvailableIds() > 200)
{
return; // We probably still have plenty of free pages left. Don't bother vacuuming just yet.
}
swappers.Vacuum(swapperIds =>
{
int pageCount = Pages.PageCount;
try
{
using (EvictionRunEvent evictions = _pageCacheTracer.beginPageEvictions(0))
{
for (int i = 0; i < pageCount; i++)
{
long pageRef = Pages.deref(i);
while (swapperIds.contains(Pages.getSwapperId(pageRef)))
{
if (Pages.tryEvict(pageRef, evictions))
{
AddFreePageToFreelist(pageRef);
break;
}
}
}
}
}
catch (IOException e)
{
throw new UncheckedIOException(e);
}
});
}
internal virtual int EvictPages(int pageCountToEvict, int clockArm, EvictionRunEvent evictionRunEvent)
{
while (pageCountToEvict > 0 && !_closed)
{
if (clockArm == Pages.PageCount)
{
clockArm = 0;
}
if (_closed)
{
// The page cache has been shut down.
return(0);
}
long pageRef = Pages.deref(clockArm);
if (Pages.isLoaded(pageRef) && Pages.decrementUsage(pageRef))
{
try
{
pageCountToEvict--;
if (Pages.tryEvict(pageRef, evictionRunEvent))
{
ClearEvictorException();
AddFreePageToFreelist(pageRef);
}
}
catch (IOException e)
{
_evictorException = e;
}
catch (System.OutOfMemoryException)
{
_evictorException = _oomException;
}
catch (Exception th)
{
_evictorException = new IOException("Eviction thread encountered a problem", th);
}
}
clockArm++;
}
return(clockArm);
}
/// <summary>
/// Scan through all the pages, one by one, and decrement their usage stamps.
/// If a usage reaches zero, we try-write-locking it, and if we get that lock,
/// we evict the page. If we don't, we move on to the next page.
/// Once we have enough free pages, we park our thread. Page-faulting will
/// unpark our thread as needed.
/// </summary>
internal virtual void ContinuouslySweepPages()
{
_evictionThread = Thread.CurrentThread;
int clockArm = 0;
while (!_closed)
{
int pageCountToEvict = ParkUntilEvictionRequired(_keepFree);
using (EvictionRunEvent evictionRunEvent = _pageCacheTracer.beginPageEvictions(pageCountToEvict))
{
clockArm = EvictPages(pageCountToEvict, clockArm, evictionRunEvent);
}
}
// The last thing we do, is signalling the shutdown of the cache via
// the freelist. This signal is looked out for in grabFreePage.
FreelistHead = _shutdownSignal;
}
