/// <summary>
///
/// </summary>
/// <param name="cache"></param>
/// <param name="evictSize"></param>
/// <returns></returns>
private IList GetSelectedKeys(CacheBase cache, long evictSize)
{
ClusteredArrayList selectedKeys = new ClusteredArrayList(100);
long sizeCount = 0;
int prvsSize = 0;
object key = null;
bool selectionComplete = false;
lock (_index.SyncRoot)
{
for (int i = 0; i < 5; i++)
{
if (!selectionComplete)
{
HashVector currentIndex = this._index[i];
if (currentIndex != null)
{
IDictionaryEnumerator ide = currentIndex.GetEnumerator();
while (ide.MoveNext())
{
key = ide.Key;
if (key != null)
{
int itemSize = cache.GetItemSize(key);
if (sizeCount + itemSize >= evictSize && sizeCount > 0)
{
if (evictSize - sizeCount > (itemSize + sizeCount) - evictSize)
selectedKeys.Add(key);
selectionComplete = true;
break;
}
else
{
selectedKeys.Add(key);
sizeCount += itemSize;
prvsSize = itemSize;
}
}
}
}
}
else
{
//break the outer loop. we have already picked up
//the keys to be evicited.
break;
}
}
}
return selectedKeys;
}
/// <summary>
/// Called by the scheduler to remove the items that has expired
/// </summary>
public bool Expire()
{
//indicates whether some items expired during this interval or not...
bool expired = false;
//muds:
//if user has updated the file then the new values will be reloaded.
_sleepInterval = Convert.ToInt32(ServiceConfiguration.ExpirationBulkRemoveDelay);
_removeThreshhold = Convert.ToInt32(ServiceConfiguration.ExpirationBulkRemoveSize);
CacheBase cacheInst = _context.CacheImpl;
CacheBase cache = _context.CacheInternal;
Cache rootCache = _context.CacheRoot;
if (cache == null)
throw new InvalidOperationException("No cache instance defined");
bool allowExpire = AllowClusteredExpiry;
//in case of replication, only the coordinator/sub-coordinator is responsible to expire the items.
if (!allowExpire) return false;
ClusteredArrayList selectedKeys = new ClusteredArrayList();
int oldItemsCount = 0;
HashVector oldeItems = null;
try
{
StartLogging();
DateTime startTime = DateTime.Now;
int currentTime = AppUtil.DiffSeconds(startTime);
int cleanSize = (int)Math.Ceiling(cache.Count * _cleanRatio);
//set the flag that we are going to expire the items.
if (_cacheLastAccessLoggingIntervalPassed >= _cacheLastAccessLoggingInterval)
{
_cacheLastAccessLoggingInterval = CacheLastAccessLoggingInterval;
_cacheLastAccessCountEnabled = IsCacheLastAccessCountEnabled;
_cacheLastAccessCountLoggingEnabled = IsCacheLastAccessLoggingEnabled;
_cacheLastAccessInterval = CacheLastAccessCountInterval;
}
else
_cacheLastAccessLoggingIntervalPassed++;
if (_cacheLastAccessCountEnabled && _cacheLastAccessCountLoggingEnabled)
{
if (_cacheLastAccessLoggingIntervalPassed >= _cacheLastAccessLoggingInterval)
{
_cacheLastAccessLoggingIntervalPassed = 0;
oldeItems = new HashVector();
}
}
lock (_mainIndex.SyncRoot)
{
IDictionaryEnumerator em = _mainIndex.GetEnumerator();
if (em != null)
{
while (em.MoveNext())
{
ExpirationHint hint = em.Value as ExpirationHint;
if (hint != null && _cacheLastAccessCountEnabled && hint is IdleExpiration)
{
IdleExpiration slidingExpHint = hint as IdleExpiration;
TimeSpan diff = AppUtil.GetDateTime(AppUtil.DiffSeconds(DateTime.Now)) - AppUtil.GetDateTime(slidingExpHint.LastAccessTime);
if (diff.TotalMinutes >= _cacheLastAccessInterval)
{
oldItemsCount++;
if (oldeItems != null)
{
oldeItems.Add(em.Key, null);
}
}
}
if (hint == null || hint.SortKey.CompareTo(currentTime) >= 0)
continue;
if (hint.DetermineExpiration(_context))
{
selectedKeys.Add(em.Key);
if (cleanSize > 0 && selectedKeys.Count == cleanSize) break;
}
}
}
}
if (NCacheLog.IsInfoEnabled) NCacheLog.Info("ExpirationManager.Expire()", String.Format("Expiry time for {0}/{1} Items: " + (DateTime.UtcNow - startTime), selectedKeys.Count, /*_expiryIndex.KeyCount*/cache.Count));
}
catch (Exception e)
{
NCacheLog.Error("ExpirationManager.Expire(bool)", "LocalCache(Expire): " + e.ToString());
}
finally
{
_context.PerfStatsColl.IncrementCacheLastAccessCountStats(oldItemsCount);
ApplyLoggs();
ClusteredArrayList dependentItems = new ClusteredArrayList();
DateTime startTime = DateTime.Now;
HashVector expiredItemTable = new HashVector();
expiredItemTable.Add(ItemRemoveReason.Expired, selectedKeys);//Time based expiration
try
{
IDictionaryEnumerator ide = expiredItemTable.GetEnumerator();
while (ide.MoveNext())
{
selectedKeys = ide.Value as ClusteredArrayList;
ItemRemoveReason removedReason = (ItemRemoveReason)ide.Key;
if (selectedKeys.Count > 0)
{
//new architectural changes begins from here.
ClusteredArrayList keysTobeRemoved = new ClusteredArrayList();
for (int i = 0; i < selectedKeys.Count && !_cacheCleared; i++)
{
keysTobeRemoved.Add(selectedKeys[i]);
if (keysTobeRemoved.Count % _removeThreshhold == 0)
{
try
{
if (this.IsDisposed) break;
OperationContext operationContext = new OperationContext(OperationContextFieldName.OperationType, OperationContextOperationType.CacheOperation);
object[][] keysExposed = keysTobeRemoved.ToInternalArray();
foreach (object[] collection in keysExposed)
{
cache.RemoveSync(collection, removedReason, false, operationContext);
}
//set the flag that item has expired from cache...
expired = true;
if (_context.PerfStatsColl != null) _context.PerfStatsColl.IncrementExpiryPerSecStatsBy(keysTobeRemoved.Count);
}
catch (Exception e)
{
NCacheLog.Error("ExpiryManager.Expire", "an error occurred while removing expired items. Error " + e.ToString());
}
keysTobeRemoved.Clear();
//we stop the activity of the current thread so that normal user operation is not affected.
Thread.Sleep(_sleepInterval);
}
}
if (!this.IsDisposed && keysTobeRemoved.Count > 0)
{
try
{
OperationContext operationContext = new OperationContext(OperationContextFieldName.OperationType, OperationContextOperationType.CacheOperation);
object[][] keysExposed = keysTobeRemoved.ToInternalArray();
foreach (object[] keyCollection in keysExposed)
{
cache.RemoveSync(keyCollection, removedReason, false, operationContext);
}
//set the flag that item has expired from cache...
expired = true;
if (_context.PerfStatsColl != null) _context.PerfStatsColl.IncrementExpiryPerSecStatsBy(keysTobeRemoved.Count);
}
catch (Exception e)
{
NCacheLog.Error("ExpiryManager.Expire", "an error occurred while removing expired items. Error " + e.ToString());
}
}
}
}
}
finally
{
_transitoryIndex.Clear();
lock (this)
{
_cacheCleared = false;
}
if (oldeItems != null)
{
StringBuilder sb = new StringBuilder();
IDictionaryEnumerator ide = oldeItems.GetEnumerator();
int count = 1;
while (ide.MoveNext())
{
sb.Append(ide.Key + ", ");
if (count % 10 == 0)
{
sb.Append("\r\n");
count = 1;
}
else
count++;
}
NCacheLog.Info(sb.ToString().Trim());
}
}
}
return expired;
}
void IEvictionPolicy.Execute(CacheBase cache, CacheRuntimeContext context, long evictSize)
{
ILogger NCacheLog = cache.Context.NCacheLog;
if (NCacheLog.IsInfoEnabled) NCacheLog.Info("LocalCache.Evict()", "Cache Size: {0}" + cache.Count.ToString());
//if user has updated the values in configuration file then new values will be reloaded.
_sleepInterval = Convert.ToInt32(ServiceConfiguration.EvictionBulkRemoveDelay);
_removeThreshhold = Convert.ToInt32(ServiceConfiguration.EvictionBulkRemoveSize);
DateTime startTime = DateTime.Now;
IList selectedKeys = this.GetSelectedKeys(cache, (long)Math.Ceiling(evictSize * _ratio));
DateTime endTime = DateTime.Now;
if (NCacheLog.IsInfoEnabled) NCacheLog.Info("LocalCache.Evict()", String.Format("Time Span for {0} Items: " + (endTime - startTime), selectedKeys.Count));
startTime = DateTime.Now;
Cache rootCache = context.CacheRoot;
ClusteredArrayList keysTobeRemoved = new ClusteredArrayList();
ClusteredArrayList dependentItems = new ClusteredArrayList();
IList removedItems = null;
IEnumerator e = selectedKeys.GetEnumerator();
int removedThreshhold = _removeThreshhold/300;
int remIteration = 0;
while (e.MoveNext())
{
object key = e.Current;
if (key == null) continue;
keysTobeRemoved.Add(key);
if (keysTobeRemoved.Count % 300 == 0)
{
try
{
OperationContext priorityEvictionOperationContext = new OperationContext();
priorityEvictionOperationContext.Add(OperationContextFieldName.OperationType, OperationContextOperationType.CacheOperation);
removedItems = cache.RemoveSync(keysTobeRemoved.ToArray(), ItemRemoveReason.Underused, false, priorityEvictionOperationContext) as ArrayList;
context.PerfStatsColl.IncrementEvictPerSecStatsBy(keysTobeRemoved.Count);
}
catch (Exception ex)
{
NCacheLog.Error("PriorityEvictionPolicy.Execute", "an error occurred while removing items. Error " + ex.ToString());
}
keysTobeRemoved.Clear();
if (removedItems != null && removedItems.Count > 0)
{
dependentItems.AddRange(removedItems);
}
remIteration++;
if (remIteration >= removedThreshhold)
{
//put some delay so that user operations are not affected.
System.Threading.Thread.Sleep(_sleepInterval*1000);
remIteration = 0;
}
}
}
if (keysTobeRemoved.Count > 0)
{
try
{
OperationContext priorityEvictionOperationContext = new OperationContext();
priorityEvictionOperationContext.Add(OperationContextFieldName.OperationType, OperationContextOperationType.CacheOperation);
removedItems = cache.RemoveSync(keysTobeRemoved.ToArray(), ItemRemoveReason.Underused, false, priorityEvictionOperationContext) as ArrayList;
context.PerfStatsColl.IncrementEvictPerSecStatsBy(keysTobeRemoved.Count);
if (removedItems != null && removedItems.Count > 0)
{
dependentItems.AddRange(removedItems);
}
}
catch (Exception ex)
{
NCacheLog.Error("PriorityEvictionPolicy.Execute", "an error occurred while removing items. Error " + ex.ToString());
}
}
if (dependentItems.Count > 0)
{
ArrayList removableList = new ArrayList();
if (rootCache != null)
{
foreach (object depenentItme in dependentItems)
{
if (depenentItme == null) continue;
removableList.Add(depenentItme);
if (removableList.Count % 100 == 0)
{
try
{
OperationContext priorityEvictionOperationContext = new OperationContext();
priorityEvictionOperationContext.Add(OperationContextFieldName.OperationType, OperationContextOperationType.CacheOperation);
rootCache.CascadedRemove(removableList, ItemRemoveReason.Underused, true, priorityEvictionOperationContext);
context.PerfStatsColl.IncrementEvictPerSecStatsBy(removableList.Count);
}
catch (Exception exc)
{
NCacheLog.Error("PriorityEvictionPolicy.Execute", "an error occurred while removing dependent items. Error " + exc.ToString());
}
removableList.Clear();
}
}
if (removableList.Count > 0)
{
try
{
OperationContext priorityEvictionOperationContext = new OperationContext();
priorityEvictionOperationContext.Add(OperationContextFieldName.OperationType, OperationContextOperationType.CacheOperation);
rootCache.CascadedRemove(removableList, ItemRemoveReason.Underused, true, priorityEvictionOperationContext);
context.PerfStatsColl.IncrementEvictPerSecStatsBy(removableList.Count);
}
catch (Exception exc)
{
NCacheLog.Error("PriorityEvictionPolicy.Execute", "an error occurred while removing dependent items. Error " + exc.ToString());
}
removableList.Clear();
}
}
}
return;
}
// Returns an IList that contains count copies of value.
//
public static ClusteredArrayList Repeat(Object value, int count)
{
if (count < 0)
throw new ArgumentOutOfRangeException("count", ResourceHelper.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
#if DEBUG
Contract.Ensures(Contract.Result<ClusteredArrayList>() != null);
Contract.EndContractBlock();
#endif
ClusteredArrayList list = new ClusteredArrayList((count > _defaultCapacity) ? count : _defaultCapacity);
for (int i = 0; i < count; i++)
list.Add(value);
return list;
}