void CalculateFileUsefullness(IRootNodeInternal root)
{
_keyValueDB.IterateRoot(root, (valueFileId, valueOfs, valueSize) =>
{
_cancellation.ThrowIfCancellationRequested();
_fileStats.GetOrFakeValueRef(valueFileId).AddLength((uint)Math.Abs(valueSize));
});
}
internal bool Run()
{
if (_keyValueDB.FileCollection.GetCount() == 0)
{
return(false);
}
_root = _keyValueDB.ReferenceAndGetOldestRoot();
try
{
var dontTouchGeneration = _keyValueDB.GetGeneration(_keyValueDB.GetTrLogFileId(_root));
var preserveKeyIndexKey =
_keyValueDB.CalculatePreserveKeyIndexKeyFromKeyIndexInfos(_keyValueDB.BuildKeyIndexInfos());
var preserveKeyIndexGeneration = _keyValueDB.CalculatePreserveKeyIndexGeneration(preserveKeyIndexKey);
InitFileStats(dontTouchGeneration);
long[] usedFilesFromOldGenerations = null;
if (preserveKeyIndexKey < uint.MaxValue)
{
var dontTouchGenerationDueToPreserve = -1L;
if (_keyValueDB.FileCollection.FileInfoByIdx(preserveKeyIndexKey) is IKeyIndex fileInfo)
{
dontTouchGenerationDueToPreserve = fileInfo.Generation;
dontTouchGenerationDueToPreserve = Math.Min(dontTouchGenerationDueToPreserve,
_keyValueDB.GetGeneration(fileInfo.TrLogFileId));
if (fileInfo.UsedFilesInOlderGenerations == null)
{
_keyValueDB.LoadUsedFilesFromKeyIndex(preserveKeyIndexKey, fileInfo);
}
usedFilesFromOldGenerations = fileInfo.UsedFilesInOlderGenerations;
}
dontTouchGeneration = Math.Min(dontTouchGeneration, dontTouchGenerationDueToPreserve);
}
var lastCommited = _keyValueDB.ReferenceAndGetLastCommitted();
try
{
if (_root != lastCommited)
{
ForbidDeleteOfFilesUsedByStillRunningOldTransaction();
}
ForbidDeletePreservingHistory(dontTouchGeneration, usedFilesFromOldGenerations);
CalculateFileUsefullness(lastCommited);
}
finally
{
_keyValueDB.DereferenceRootNodeInternal(lastCommited);
}
MarkTotallyUselessFilesAsUnknown();
var totalWaste = CalcTotalWaste();
_keyValueDB.Logger?.CompactionStart(totalWaste);
if (IsWasteSmall(totalWaste))
{
if (_keyValueDB.DistanceFromLastKeyIndex(_root) > (ulong)(_keyValueDB.MaxTrLogFileSize / 4))
{
_keyValueDB.CreateIndexFile(_cancellation, preserveKeyIndexGeneration);
}
_keyValueDB.FileCollection.DeleteAllUnknownFiles();
return(false);
}
long btreesCorrectInTransactionId;
var toRemoveFileIds = new List <uint>();
do
{
_newPositionMap = new Dictionary <ulong, ulong>();
do
{
CompactOnePureValueFileIteration(toRemoveFileIds);
totalWaste = CalcTotalWaste();
} while (_newPositionMap.Count * 50 / (1024 * 1024) < _keyValueDB.CompactorRamLimitInMb &&
!IsWasteSmall(totalWaste));
btreesCorrectInTransactionId = _keyValueDB.ReplaceBTreeValues(_cancellation, _newPositionMap);
} while (!IsWasteSmall(totalWaste));
_keyValueDB.CreateIndexFile(_cancellation, preserveKeyIndexGeneration);
if (_keyValueDB.AreAllTransactionsBeforeFinished(btreesCorrectInTransactionId))
{
_keyValueDB.MarkAsUnknown(toRemoveFileIds);
}
_keyValueDB.FileCollection.DeleteAllUnknownFiles();
return(true);
}
finally
{
_keyValueDB.DereferenceRootNodeInternal(_root);
_root = null;
}
}