private ActualKeyScope GetActualKey(TreePage page, int pos, out TreeNodeHeader *node, out Slice key) { DecompressedLeafPage decompressedLeafPage = null; node = page.GetNode(pos); var scope = TreeNodeHeader.ToSlicePtr(_tx.Allocator, node, out key); while (key.Size == 0) { Debug.Assert(page.IsBranch); page = _tree.GetReadOnlyTreePage(node->PageNumber); if (page.IsCompressed == false) { node = page.GetNode(0); } else { decompressedLeafPage?.Dispose(); decompressedLeafPage = _tree.DecompressPage(page, skipCache: true); if (decompressedLeafPage.NumberOfEntries > 0) { node = decompressedLeafPage.GetNode(0); } else { // we have empty page after decompression (each compressed entry has a corresponding CompressionTombstone) // we can safely use the node key of first tombstone (they have proper order) node = page.GetNode(0); } } scope.Dispose(); scope = TreeNodeHeader.ToSlicePtr(_tx.Allocator, node, out key); } return(new ActualKeyScope { DecompressedLeafPage = decompressedLeafPage, ExternalScope = scope }); }
private void HandleTombstone(DecompressedLeafPage decompressedPage, Slice nodeKey, DecompressionUsage usage) { decompressedPage.Search(_llt, nodeKey); if (decompressedPage.LastMatch != 0) { return; } var node = decompressedPage.GetNode(decompressedPage.LastSearchPosition); if (usage == DecompressionUsage.Write) { State.NumberOfEntries--; if (node->Flags == TreeNodeFlags.PageRef) { var overflowPage = GetReadOnlyTreePage(node->PageNumber); FreePage(overflowPage); } } decompressedPage.RemoveNode(decompressedPage.LastSearchPosition); }
private ActualKeyScope GetActualKey(TreePage page, int pos, out TreeNodeHeader *node, out Slice key) { DecompressedLeafPage decompressedLeafPage = null; node = page.GetNode(pos); var scope = TreeNodeHeader.ToSlicePtr(_tx.Allocator, node, out key); while (key.Size == 0) { Debug.Assert(page.IsBranch); page = _tree.GetReadOnlyTreePage(node->PageNumber); if (page.IsCompressed == false) { node = page.GetNode(0); } else { decompressedLeafPage?.Dispose(); decompressedLeafPage = _tree.DecompressPage(page, DecompressionUsage.Read, skipCache: true); if (decompressedLeafPage.NumberOfEntries > 0) { if (page.NumberOfEntries == 0) { node = decompressedLeafPage.GetNode(0); } else { // we want to find the smallest key in compressed page // it can be inside compressed part or not compressed one // in particular, it can be the key of compression tombstone node that we don't see after decompression // so we need to take first keys from decompressed and compressed page and compare them var decompressedNode = decompressedLeafPage.GetNode(0); var compressedNode = page.GetNode(0); using (TreeNodeHeader.ToSlicePtr(_tx.Allocator, decompressedNode, out var firstDecompressedKey)) using (TreeNodeHeader.ToSlicePtr(_tx.Allocator, compressedNode, out var firstCompressedKey)) { node = SliceComparer.CompareInline(firstDecompressedKey, firstCompressedKey) > 0 ? compressedNode : decompressedNode; } } } else { // we have empty page after decompression (each compressed entry has a corresponding CompressionTombstone) // we can safely use the node key of first tombstone (they have proper order) node = page.GetNode(0); } } scope.Dispose(); scope = TreeNodeHeader.ToSlicePtr(_tx.Allocator, node, out key); } return(new ActualKeyScope { DecompressedLeafPage = decompressedLeafPage, ExternalScope = scope }); }