private static unsafe void RenderPage(Tree tree, TreePage page, TextWriter sw, string text, bool open)
{
sw.WriteLine(
"<ul><li><input type='checkbox' id='page-{0}' {3} /><label for='page-{0}'>{4}: Page {0:#,#;;0} - {1} - {2:#,#;;0} entries {5}</label><ul>",
page.PageNumber, page.IsLeaf ? "Leaf" : "Branch", page.NumberOfEntries, open ? "checked" : "", text,
page.IsCompressed? $"(Compressed ({page.CompressionHeader->NumberOfCompressedEntries} entries [uncompressed/compressed: {page.CompressionHeader->UncompressedSize}/{page.CompressionHeader->CompressedSize}])" : string.Empty);
for (int i = 0; i < page.NumberOfEntries; i++)
{
var nodeHeader = page.GetNode(i);
string key;
Slice keySlice;
using (TreeNodeHeader.ToSlicePtr(tree.Llt.Allocator, nodeHeader, out keySlice))
{
key = keySlice.ToString();
}
if (page.IsLeaf)
{
sw.Write("<li>{0} {1} - size: {2:#,#}</li>", key, nodeHeader->Flags, tree.GetDataSize(nodeHeader));
}
else
{
var pageNum = nodeHeader->PageNumber;
if (i == 0)
{
key = "[smallest]";
}
RenderPage(tree, tree.GetReadOnlyTreePage(pageNum), sw, key, false);
}
}
sw.WriteLine("</ul></li></ul>");
}
protected unsafe Tuple <Slice, Slice> ReadKey(Transaction txh, Tree tree, Slice key)
{
TreeNodeHeader *node;
tree.FindPageFor(key, out node);
if (node == null)
{
return(null);
}
Slice item1;
TreeNodeHeader.ToSlicePtr(txh.Allocator, node, out item1);
if (!SliceComparer.Equals(item1, key))
{
return(null);
}
Slice item2;
Slice.External(txh.Allocator, (byte *)node + node->KeySize + Constants.Tree.NodeHeaderSize, (ushort)node->DataSize, out item2);
return(Tuple.Create(item1, item2));
}
public TreeNodeHeader *Original_WithPrefetch_Search(TreePage page, ByteStringContext allocator, Slice key)
{
int numberOfEntries = page.NumberOfEntries;
if (numberOfEntries == 0)
{
goto NoEntries;
}
int lastMatch = -1;
int lastSearchPosition = 0;
SliceOptions options = key.Options;
if (options == SliceOptions.Key)
{
if (numberOfEntries == 1)
{
goto SingleEntryKey;
}
int low = page.IsLeaf ? 0 : 1;
int high = numberOfEntries - 1;
int position = 0;
ushort *offsets = page.KeysOffsets;
byte * @base = page.Base;
while (low <= high)
{
position = (low + high) >> 1;
var node = (TreeNodeHeader *)(@base + offsets[position]);
Slice pageKey;
using (TreeNodeHeader.ToSlicePtr(allocator, node, out pageKey))
{
Sse.Prefetch0(pageKey.Content.Ptr);
lastMatch = SliceComparer.CompareInline(key, pageKey);
}
if (lastMatch == 0)
{
break;
}
if (lastMatch > 0)
{
low = position + 1;
}
else
{
high = position - 1;
}
}
if (lastMatch > 0) // found entry less than key
{
position++; // move to the smallest entry larger than the key
}
lastSearchPosition = position;
goto MultipleEntryKey;
}
if (options == SliceOptions.BeforeAllKeys)
{
lastMatch = 1;
goto MultipleEntryKey;
}
if (options == SliceOptions.AfterAllKeys)
{
lastSearchPosition = numberOfEntries - 1;
goto MultipleEntryKey;
}
return(null);
NoEntries:
{
page.LastSearchPosition = 0;
page.LastMatch = 1;
return(null);
}
SingleEntryKey:
{
var node = page.GetNode(0);
Slice pageKey;
using (TreeNodeHeader.ToSlicePtr(allocator, node, out pageKey))
{
page.LastMatch = SliceComparer.CompareInline(key, pageKey);
}
page.LastSearchPosition = page.LastMatch > 0 ? 1 : 0;
return(page.LastSearchPosition == 0 ? node : null);
}
MultipleEntryKey:
{
page.LastMatch = lastMatch;
page.LastSearchPosition = lastSearchPosition;
if (lastSearchPosition >= numberOfEntries)
{
return(null);
}
return(page.GetNode(lastSearchPosition));
}
}
