4.11 The DBTUX Block

This kernel block provides local management of ordered indexes. It consists of the following files found in the storage/ndb/src/kernel/blocks/dbtux directory:

• DbtuxCmp.cpp: Implements routines to search by key versus node prefix or entry. The comparison starts at a given attribute position, which is updated by the number of equal initial attributes found. The entry data may be partial, in which case CmpUnknown may be returned. The attributes are normalized and have a variable size, given in words.

• DbtuxGen.cpp: Implements initialization routines used in node starts and restarts.

• DbtuxMaint.cpp: Contains routines used to maintain indexes.

• DbtuxNode.cpp: Implements routines for node creation, allocation, and deletion operations. Also assigns lists of scans to nodes.

• DbtuxSearch.cpp: Provides routines for handling node scan request messages.

• DbtuxTree.cpp: Routines for performing node tree operations.

• Times.txt: Contains some (old) performance figures from tests runs on operations using ordered indexes. Of historical interest only.

• DbtuxDebug.cpp: Debugging code for dumping node states.

• Dbtux.hpp: Contains Dbtux class definition.

• DbtuxMeta.cpp: Routines for creating, setting, and dropping indexes. Also provides means of aborting these operations in the event of failure.

• DbtuxScan.cpp: Routines for performing index scans.

• DbtuxStat.cpp: Implements methods for obtaining node statistics.

• tuxstatus.html: 2004-01-30 status report on ordered index implementation. Of historical interest only.

DBQTUX is a subtype of this block, used for query and recovery threads, added in NDB 8.0.23.