private byte *SplitPageInHalf(Page rightPage)
{
var currentIndex = _page.LastSearchPosition;
var newPosition = true;
var splitIndex = _page.NumberOfEntries / 2;
if (currentIndex < splitIndex)
{
newPosition = false;
}
if (_page.IsLeaf)
{
splitIndex = AdjustSplitPosition(_newKey, _len, _page, currentIndex, splitIndex, ref newPosition);
}
// here we the current key is the separator key and can go either way, so
// use newPosition to decide if it stays on the left node or moves to the right
Slice seperatorKey;
if (currentIndex == splitIndex && newPosition)
{
seperatorKey = _newKey;
}
else
{
var node = _page.GetNode(splitIndex);
seperatorKey = new Slice(node);
}
AddSeperatorToParentPage(rightPage, seperatorKey);
// move the actual entries from page to right page
var nKeys = _page.NumberOfEntries;
for (int i = splitIndex; i < nKeys; i++)
{
var node = _page.GetNode(i);
var itemsMoved = 1;
if (_page.IsBranch && rightPage.NumberOfEntries == 0)
{
rightPage.CopyNodeDataToEndOfPage(node, Slice.Empty);
itemsMoved = _tx.Pager.Get(_tx, node->PageNumber).ItemCount;
}
else
{
rightPage.CopyNodeDataToEndOfPage(node);
}
rightPage.ItemCount += itemsMoved;
_page.ItemCount -= itemsMoved;
}
_page.Truncate(_tx, splitIndex);
byte *dataPos;
// actually insert the new key
return((currentIndex > splitIndex || newPosition && currentIndex == splitIndex)
? InsertNewKey(rightPage) : InsertNewKey(_page));
}
private byte *SplitPageInHalf(Page rightPage)
{
int currentIndex = _page.LastSearchPosition;
bool newPosition = true;
int splitIndex = _page.NumberOfEntries / 2;
if (currentIndex < splitIndex)
{
newPosition = false;
}
if (_page.IsLeaf)
{
splitIndex = AdjustSplitPosition(currentIndex, splitIndex, ref newPosition);
}
var currentKey = _page.GetNodeKey(splitIndex);
// here the current key is the separator key and can go either way, so
// use newPosition to decide if it stays on the left node or moves to the right
MemorySlice seperatorKey;
if (currentIndex == splitIndex && newPosition)
{
seperatorKey = currentKey.Compare(_newKey) < 0 ? currentKey : _newKey;
}
else
{
seperatorKey = currentKey;
}
AddSeparatorToParentPage(rightPage.PageNumber, seperatorKey);
MemorySlice instance = _page.CreateNewEmptyKey();
// move the actual entries from page to right page
ushort nKeys = _page.NumberOfEntries;
for (int i = splitIndex; i < nKeys; i++)
{
NodeHeader *node = _page.GetNode(i);
if (_page.IsBranch && rightPage.NumberOfEntries == 0)
{
rightPage.CopyNodeDataToEndOfPage(node, _tree.KeysPrefixing ? (MemorySlice)PrefixedSlice.BeforeAllKeys : Slice.BeforeAllKeys);
}
else
{
_page.SetNodeKey(node, ref instance);
var key = rightPage.PrepareKeyToInsert(instance, rightPage.NumberOfEntries);
rightPage.CopyNodeDataToEndOfPage(node, key);
}
}
_page.Truncate(_tx, splitIndex);
// actually insert the new key
return((currentIndex > splitIndex || newPosition && currentIndex == splitIndex)
? InsertNewKey(rightPage)
: InsertNewKey(_page));
}
private byte *SplitPageInHalf(Page rightPage)
{
int currentIndex = _page.LastSearchPosition;
bool newPosition = true;
int splitIndex = _page.NumberOfEntries / 2;
if (currentIndex < splitIndex)
{
newPosition = false;
}
if (_page.IsLeaf)
{
splitIndex = AdjustSplitPosition(_newKey, _len, _page, currentIndex, splitIndex, ref newPosition);
}
NodeHeader *currentNode = _page.GetNode(splitIndex);
var currentKey = new Slice(currentNode);
// here we the current key is the separator key and can go either way, so
// use newPosition to decide if it stays on the left node or moves to the right
Slice seperatorKey;
if (currentIndex == splitIndex && newPosition)
{
seperatorKey = currentKey.Compare(_newKey) < 0 ? currentKey : _newKey;
}
else
{
seperatorKey = currentKey;
}
AddSeparatorToParentPage(rightPage, seperatorKey);
// move the actual entries from page to right page
ushort nKeys = _page.NumberOfEntries;
for (int i = splitIndex; i < nKeys; i++)
{
NodeHeader *node = _page.GetNode(i);
if (_page.IsBranch && rightPage.NumberOfEntries == 0)
{
rightPage.CopyNodeDataToEndOfPage(node, Slice.Empty);
}
else
{
rightPage.CopyNodeDataToEndOfPage(node);
}
}
_page.Truncate(_tx, splitIndex);
// actually insert the new key
return((currentIndex > splitIndex || newPosition && currentIndex == splitIndex)
? InsertNewKey(rightPage)
: InsertNewKey(_page));
}
private byte *SplitPageInHalf(Page rightPage)
{
bool toRight;
var currentIndex = _page.LastSearchPosition;
var splitIndex = _page.NumberOfEntries / 2;
if (currentIndex <= splitIndex)
{
toRight = false;
}
else
{
toRight = true;
var leftPageEntryCount = splitIndex;
var rightPageEntryCount = _page.NumberOfEntries - leftPageEntryCount + 1;
if (rightPageEntryCount > leftPageEntryCount)
{
splitIndex++;
Debug.Assert(splitIndex < _page.NumberOfEntries);
}
}
PrefixNode[] prefixes = null;
if (_tree.KeysPrefixing && _page.HasPrefixes)
{
prefixes = _page.GetPrefixes();
}
if (_page.IsLeaf || prefixes != null)
{
splitIndex = AdjustSplitPosition(currentIndex, splitIndex, prefixes, ref toRight);
}
var currentKey = _page.GetNodeKey(splitIndex);
MemorySlice seperatorKey;
if (toRight && splitIndex == currentIndex)
{
seperatorKey = currentKey.Compare(_newKey) < 0 ? currentKey : _newKey;
}
else
{
seperatorKey = currentKey;
}
Page parentOfRight;
AddSeparatorToParentPage(rightPage.PageNumber, seperatorKey, out parentOfRight);
var parentOfPage = _cursor.CurrentPage;
MemorySlice instance = _page.CreateNewEmptyKey();
if (prefixes != null)
{
for (int i = 0; i < prefixes.Length; i++)
{
var prefix = prefixes[i];
rightPage.WritePrefix(new Slice(prefix.ValuePtr, prefix.PrefixLength), i);
}
}
bool addedAsImplicitRef = false;
if (_page.IsBranch && toRight && seperatorKey == _newKey)
{
// _newKey needs to be inserted as first key (BeforeAllKeys) to the right page, so we need to add it before we move entries from the current page
AddNodeToPage(rightPage, 0, _tree.KeysPrefixing ? (MemorySlice)PrefixedSlice.BeforeAllKeys : Slice.BeforeAllKeys);
addedAsImplicitRef = true;
}
// move the actual entries from page to right page
ushort nKeys = _page.NumberOfEntries;
for (int i = splitIndex; i < nKeys; i++)
{
NodeHeader *node = _page.GetNode(i);
if (_page.IsBranch && rightPage.NumberOfEntries == 0)
{
rightPage.CopyNodeDataToEndOfPage(node, _tree.KeysPrefixing ? (MemorySlice)PrefixedSlice.BeforeAllKeys : Slice.BeforeAllKeys);
}
else
{
_page.SetNodeKey(node, ref instance);
var key = rightPage.PrepareKeyToInsert(instance, rightPage.NumberOfEntries);
rightPage.CopyNodeDataToEndOfPage(node, key);
}
}
_page.Truncate(_tx, splitIndex);
byte *pos;
if (addedAsImplicitRef == false)
{
try
{
if (toRight && _cursor.CurrentPage.PageNumber != parentOfRight.PageNumber)
{
// modify the cursor if we are going to insert to the right page
_cursor.Pop();
_cursor.Push(parentOfRight);
}
// actually insert the new key
pos = toRight ? InsertNewKey(rightPage) : InsertNewKey(_page);
}
catch (InvalidOperationException e)
{
if (e.Message.StartsWith("The page is full and cannot add an entry") == false)
{
throw;
}
throw new InvalidOperationException(GatherDetailedDebugInfo(rightPage, currentKey, seperatorKey, currentIndex, splitIndex, toRight), e);
}
}
else
{
pos = null;
_cursor.Push(rightPage);
}
if (_page.IsBranch) // remove a branch that has only one entry, the page ref needs to be added to the parent of the current page
{
Debug.Assert(_page.NumberOfEntries > 0);
Debug.Assert(rightPage.NumberOfEntries > 0);
if (_page.NumberOfEntries == 1)
{
RemoveBranchWithOneEntry(_page, parentOfPage);
}
if (rightPage.NumberOfEntries == 1)
{
RemoveBranchWithOneEntry(rightPage, parentOfRight);
}
}
return(pos);
}
private byte *SplitPageInHalf(Page rightPage)
{
int currentIndex = _page.LastSearchPosition;
bool newPosition = true;
int splitIndex = _page.NumberOfEntries / 2;
if (currentIndex < splitIndex)
{
newPosition = false;
}
PrefixNode[] prefixes = null;
if (_tree.KeysPrefixing && _page.HasPrefixes)
{
prefixes = _page.GetPrefixes();
}
if (_page.IsLeaf || prefixes != null)
{
splitIndex = AdjustSplitPosition(currentIndex, splitIndex, prefixes, ref newPosition);
}
var currentKey = _page.GetNodeKey(splitIndex);
// here the current key is the separator key and can go either way, so
// use newPosition to decide if it stays on the left node or moves to the right
MemorySlice seperatorKey;
if (currentIndex == splitIndex && newPosition)
{
seperatorKey = currentKey.Compare(_newKey) < 0 ? currentKey : _newKey;
}
else
{
seperatorKey = currentKey;
}
AddSeparatorToParentPage(rightPage.PageNumber, seperatorKey);
MemorySlice instance = _page.CreateNewEmptyKey();
if (prefixes != null)
{
for (int i = 0; i < prefixes.Length; i++)
{
var prefix = prefixes[i];
rightPage.WritePrefix(new Slice(prefix.ValuePtr, prefix.PrefixLength), i);
}
}
// move the actual entries from page to right page
ushort nKeys = _page.NumberOfEntries;
for (int i = splitIndex; i < nKeys; i++)
{
NodeHeader *node = _page.GetNode(i);
if (_page.IsBranch && rightPage.NumberOfEntries == 0)
{
rightPage.CopyNodeDataToEndOfPage(node, _tree.KeysPrefixing ? (MemorySlice)PrefixedSlice.BeforeAllKeys : Slice.BeforeAllKeys);
}
else
{
_page.SetNodeKey(node, ref instance);
var key = rightPage.PrepareKeyToInsert(instance, rightPage.NumberOfEntries);
rightPage.CopyNodeDataToEndOfPage(node, key);
}
}
_page.Truncate(_tx, splitIndex);
// actually insert the new key
try
{
return((currentIndex > splitIndex || newPosition && currentIndex == splitIndex)
? InsertNewKey(rightPage)
: InsertNewKey(_page));
}
catch (InvalidOperationException e)
{
if (e.Message.StartsWith("The page is full and cannot add an entry"))
{
var debugInfo = new StringBuilder();
debugInfo.AppendFormat("\r\n_tree.Name: {0}\r\n", _tree.Name);
debugInfo.AppendFormat("_newKey: {0}, _len: {1}, needed space: {2}\r\n", _newKey, _len, _page.GetRequiredSpace(_newKey, _len));
debugInfo.AppendFormat("currentKey: {0}, seperatorKey: {1}\r\n", currentKey, seperatorKey);
debugInfo.AppendFormat("currentIndex: {0}\r\n", currentIndex);
debugInfo.AppendFormat("splitIndex: {0}\r\n", splitIndex);
debugInfo.AppendFormat("newPosition: {0}\r\n", newPosition);
debugInfo.AppendFormat("_page info: flags - {0}, # of entries {1}, size left: {2}, calculated size left: {3}\r\n", _page.Flags, _page.NumberOfEntries, _page.SizeLeft, _page.CalcSizeLeft());
for (int i = 0; i < _page.NumberOfEntries; i++)
{
var node = _page.GetNode(i);
var key = _page.GetNodeKey(node);
debugInfo.AppendFormat("{0} - {2} {1}\r\n", key,
node->DataSize, node->Flags == NodeFlags.Data ? "Size" : "Page");
}
debugInfo.AppendFormat("rightPage info: flags - {0}, # of entries {1}, size left: {2}, calculated size left: {3}\r\n", rightPage.Flags, rightPage.NumberOfEntries, rightPage.SizeLeft, rightPage.CalcSizeLeft());
for (int i = 0; i < rightPage.NumberOfEntries; i++)
{
var node = rightPage.GetNode(i);
var key = rightPage.GetNodeKey(node);
debugInfo.AppendFormat("{0} - {2} {1}\r\n", key,
node->DataSize, node->Flags == NodeFlags.Data ? "Size" : "Page");
}
throw new InvalidOperationException(debugInfo.ToString(), e);
}
throw;
}
}