/// <summary>
/// Delete the Collection for recycling
/// </summary>
public void Delete(Algorithm.Collection.ICollectionOnDisk parent)
{
if (HeaderData != null && HeaderData.OccupiedBlocksHead != null)
{
//** add deleted collection start and end block info to the deleted blocks collection of the File
var dbi = new DeletedBlockInfo
{
StartBlockAddress = HeaderData.OccupiedBlocksHead.DataAddress,
EndBlockAddress = HeaderData.EndAllocatableAddress
};
bool oc = false;
if (parent.File.DeletedCollections != null)
{
oc = ((Algorithm.BTree.IBTreeAlgorithm)parent.File.DeletedCollections).ChangeRegistry;
((Algorithm.BTree.IBTreeAlgorithm)parent.File.DeletedCollections).ChangeRegistry =
((Algorithm.BTree.IBTreeAlgorithm)parent).ChangeRegistry;
parent.File.DeletedCollections.Add(dbi);
}
//** Reset count to 0 and save the header to disk
HeaderData.Count = 0;
if (!parent.IsTransactionStore)
{
parent.RegisterChange(true);
}
if (parent.File.DeletedCollections != null)
{
((Algorithm.BTree.IBTreeAlgorithm)parent.File.DeletedCollections).ChangeRegistry = oc;
}
HeaderData.Clear();
}
}
public object Clone()
{
DeletedBlockInfo r = new DeletedBlockInfo();
r.Count = Count;
r.StartBlockAddress = StartBlockAddress;
r.IsDirty = IsDirty;
r.HintSizeOnDisk = HintSizeOnDisk;
r.EndBlockAddress = EndBlockAddress;
if (DiskBuffer != null)
{
r.DiskBuffer = (Sop.DataBlock)DiskBuffer.Clone();
}
return(r);
}
internal bool ResurfaceDeletedBlockNextSegment(CollectionOnDisk parent,
DeletedBlockInfo dbi, long segmentEnd)
{
//** read next segment of deleted collection
Sop.DataBlock db = CreateBlock(parent.DataBlockSize);
long address = segmentEnd - (int)parent.DataBlockSize;
db = ReadBlockFromDisk(parent, address, true, true, db);
if (db.InternalNextBlockAddress >= 0)
{
dbi.StartBlockAddress = db.InternalNextBlockAddress;
if (parent.File.DeletedCollections != null)
{
parent.File.DeletedCollections.SetTop(dbi);
}
return(true);
}
return(false);
}
/// <summary>
/// Allocate next available block on disk.
/// Returns true if all blocks had been allocated, false otherwise.
/// </summary>
/// <param name="parent"></param>
/// <param name="block"></param>
/// <param name="isHead"></param>
/// <param name="isCollectionBlock"></param>
/// <param name="addToMru"> </param>
/// <returns></returns>
private bool AllocateNextBlock(Algorithm.Collection.ICollectionOnDisk parent, Sop.DataBlock block,
bool isHead, bool isCollectionBlock, bool addToMru)
{
bool isBlockLocallyRecycled = false;
HeaderData hd = HeaderData;
if (hd == null && parent.Parent is CollectionOnDisk)
{
hd = ((CollectionOnDisk)parent.Parent).HeaderData;
}
bool willRecycle = hd != null && hd.RecycledSegment != null && hd.RecycledSegment.Count > 0;
if (!willRecycle && hd.NextAllocatableAddress + block.Length <= hd.EndAllocatableAddress)
{
AllocateAvailableBlock((CollectionOnDisk)parent, hd, block);
}
else
{
if (parent.File.Server.HasTrashBin && !willRecycle)
{
if (isCollectionBlock)
{
willRecycle = parent.File.DeletedCollections != null &&
parent.File.DeletedCollections.Count > 0;
}
//** prioritize block recycling if there are plenty of deleted blocks
if (!willRecycle && ((CollectionOnDisk)parent).DeletedBlocks != null)
{
willRecycle = ((CollectionOnDisk)parent).DeletedBlocks.Count > 0 ||
parent.File.DeletedCollections.Count > 0;
}
if (!willRecycle && isHead)
{
willRecycle = parent.File.DeletedCollections != null &&
parent.File.DeletedCollections.Count > 0;
}
}
DeletedBlockInfo dbi = null;
if (willRecycle)
{
int totalBlockSize;
bool fromCollection;
if (isCollectionBlock)
{
if (parent.File.DeletedCollections != null && parent.File.DeletedCollections.Count > 0)
{
dbi = RecycleBlock(parent, block, true, out totalBlockSize, out fromCollection);
}
}
if (
dbi != null ||
((((CollectionOnDisk)parent).DeletedBlocksCount) > 0 &&
(dbi =
RecycleBlock(parent, block, isCollectionBlock, out totalBlockSize, out fromCollection)) !=
null)
)
{
#region Recycle Deleted Block
if (dbi.IsContiguousBlock)
{
#region Contiguous blocks can only be from Collection.DeletedBlocks
if (block.DataAddress == -1)
{
long address = dbi.StartBlockAddress;
Sop.DataBlock db = block;
int blockLength = (int)parent.DataBlockSize;
while (db != null)
{
dbi.Count--;
db.DataAddress = address;
address += blockLength;
db = db.Next;
}
}
isBlockLocallyRecycled = true;
#endregion
}
else
{
#region Recycled block is from a deleted collection of the File
int growthSizeInNob = parent.File.StoreGrowthSizeInNob;
block.DataAddress = dbi.StartBlockAddress;
hd.StartAllocatableAddress = dbi.StartBlockAddress;
hd.EndAllocatableAddress = hd.StartAllocatableAddress +
(short)parent.File.DataBlockSize * growthSizeInNob;
Log.Logger.Instance.Log(Log.LogLevels.Verbose,
"Recycled region {0}, Size {1} from {2} DeletedCollections",
dbi.StartBlockAddress, hd.EndAllocatableAddress - hd.StartAllocatableAddress,
parent.File.Filename);
if (parent.Transaction != null)
{
((Transaction.TransactionBase)parent.Transaction).Register(
Sop.Transaction.ActionType.RecycleCollection,
(CollectionOnDisk)parent, dbi.StartBlockAddress,
hd.EndAllocatableAddress - hd.StartAllocatableAddress);
}
if (dbi.EndBlockAddress == hd.EndAllocatableAddress)
{
if (parent.File.DeletedCollections != null)
{
parent.File.DeletedCollections.RemoveTop();
}
}
else
{
//** read next segment of deleted collection
if (
!ResurfaceDeletedBlockNextSegment((CollectionOnDisk)parent, dbi,
hd.EndAllocatableAddress))
{
if (parent.File.DeletedCollections != null)
{
parent.File.DeletedCollections.Remove(dbi.StartBlockAddress);
}
}
}
hd.NextAllocatableAddress = hd.StartAllocatableAddress + block.Length;
hd.DiskBuffer.IsDirty = true;
hd.IsModifiedInTransaction = true;
#endregion
}
#endregion
}
}
if (dbi == null)
{
if (hd.NextAllocatableAddress + block.Length <= hd.EndAllocatableAddress)
{
AllocateAvailableBlock((CollectionOnDisk)parent, hd, block);
}
else
{
AllocateOnNextSegment((CollectionOnDisk)parent, hd, block);
}
}
}
#region Add Block to MRU
if (hd.OccupiedBlocksHead == null)
{
hd.OccupiedBlocksHead = CreateBlock((DataBlockSize)block.Length);
hd.OccupiedBlocksHead.DataAddress = block.DataAddress;
if (hd.OccupiedBlocksTail == null)
{
hd.OccupiedBlocksTail = CreateBlock((DataBlockSize)block.Length);
}
}
else if (isBlockLocallyRecycled)
{
//** reload & update the InternalNextBlockAddress to keep ("low-level") segments' link intact...
Sop.DataBlock db = block;
while (db != null)
{
if ((db.DataAddress + (int)parent.DataBlockSize) %
(parent.File.Profile.StoreGrowthSizeInNob * (int)parent.DataBlockSize) == 0)
{
Sop.DataBlock db2 = CreateBlock(parent.DataBlockSize);
db2 = ReadBlockFromDisk(parent, db.DataAddress, true, true, db2);
db.InternalNextBlockAddress = db2.InternalNextBlockAddress;
}
db = db.Next;
}
//** add to MRU cache if requested...
return(true);
}
else
{
if ((hd.OccupiedBlocksTail.DataAddress + (int)parent.DataBlockSize) %
(parent.File.Profile.StoreGrowthSizeInNob * (int)parent.DataBlockSize) == 0)
{
Sop.DataBlock db = ReadBlockFromDisk(parent, hd.OccupiedBlocksTail.DataAddress, false);
db.InternalNextBlockAddress = block.DataAddress;
this.SetDiskAddress(parent, db, addToMru);
long dbId = GetId(db);
((CollectionOnDisk)parent).Blocks[dbId] = db;
}
}
hd.OccupiedBlocksTail.DataAddress = block.DataAddress;
#endregion
return(false);
}
