dbtux.hpp

mysql-5.0.22.tar.gz源码包

/* Copyright (C) 2003 MySQL AB

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

#ifndef DBTUX_H
#define DBTUX_H

#include <ndb_limits.h>
#include <SimulatedBlock.hpp>
#include <AttributeDescriptor.hpp>
#include <AttributeHeader.hpp>
#include <ArrayPool.hpp>
#include <DataBuffer.hpp>
#include <md5_hash.hpp>

// big brother
#include <Dbtup.hpp>

// signal classes
#include <signaldata/DictTabInfo.hpp>
#include <signaldata/TuxContinueB.hpp>
#include <signaldata/TupFrag.hpp>
#include <signaldata/AlterIndx.hpp>
#include <signaldata/DropTab.hpp>
#include <signaldata/TuxMaint.hpp>
#include <signaldata/AccScan.hpp>
#include <signaldata/TuxBound.hpp>
#include <signaldata/NextScan.hpp>
#include <signaldata/AccLock.hpp>
#include <signaldata/DumpStateOrd.hpp>

// debug
#ifdef VM_TRACE
#include <NdbOut.hpp>
#include <OutputStream.hpp>
#endif

// jams
#undef jam
#undef jamEntry
#ifdef DBTUX_GEN_CPP
#define jam()           jamLine(10000 + __LINE__)
#define jamEntry()      jamEntryLine(10000 + __LINE__)
#endif
#ifdef DBTUX_META_CPP
#define jam()           jamLine(20000 + __LINE__)
#define jamEntry()      jamEntryLine(20000 + __LINE__)
#endif
#ifdef DBTUX_MAINT_CPP
#define jam()           jamLine(30000 + __LINE__)
#define jamEntry()      jamEntryLine(30000 + __LINE__)
#endif
#ifdef DBTUX_NODE_CPP
#define jam()           jamLine(40000 + __LINE__)
#define jamEntry()      jamEntryLine(40000 + __LINE__)
#endif
#ifdef DBTUX_TREE_CPP
#define jam()           jamLine(50000 + __LINE__)
#define jamEntry()      jamEntryLine(50000 + __LINE__)
#endif
#ifdef DBTUX_SCAN_CPP
#define jam()           jamLine(60000 + __LINE__)
#define jamEntry()      jamEntryLine(60000 + __LINE__)
#endif
#ifdef DBTUX_SEARCH_CPP
#define jam()           jamLine(70000 + __LINE__)
#define jamEntry()      jamEntryLine(70000 + __LINE__)
#endif
#ifdef DBTUX_CMP_CPP
#define jam()           jamLine(80000 + __LINE__)
#define jamEntry()      jamEntryLine(80000 + __LINE__)
#endif
#ifdef DBTUX_DEBUG_CPP
#define jam()           jamLine(90000 + __LINE__)
#define jamEntry()      jamEntryLine(90000 + __LINE__)
#endif
#ifndef jam
#define jam()           jamLine(__LINE__)
#define jamEntry()      jamEntryLine(__LINE__)
#endif

#undef max
#undef min

class Configuration;

class Dbtux : public SimulatedBlock {
public:
  Dbtux(const Configuration& conf);
  virtual ~Dbtux();

  // pointer to TUP instance in this thread
  Dbtup* c_tup;

private:
  // sizes are in words (Uint32)
  STATIC_CONST( MaxIndexFragments = 2 * MAX_FRAG_PER_NODE );
  STATIC_CONST( MaxIndexAttributes = MAX_ATTRIBUTES_IN_INDEX );
  STATIC_CONST( MaxAttrDataSize = 2048 );
public:
  STATIC_CONST( DescPageSize = 256 );
private:
  STATIC_CONST( MaxTreeNodeSize = MAX_TTREE_NODE_SIZE );
  STATIC_CONST( MaxPrefSize = MAX_TTREE_PREF_SIZE );
  STATIC_CONST( ScanBoundSegmentSize = 7 );
  STATIC_CONST( MaxAccLockOps = MAX_PARALLEL_OP_PER_SCAN );
  BLOCK_DEFINES(Dbtux);

  // forward declarations
  struct DescEnt;

  /*
   * Pointer to array of Uint32.
   */
  struct Data {
  private:
    Uint32* m_data;
  public:
    Data();
    Data(Uint32* data);
    Data& operator=(Uint32* data);
    operator Uint32*() const;
    Data& operator+=(size_t n);
    AttributeHeader& ah() const;
  };
  friend class Data;

  /*
   * Pointer to array of constant Uint32.
   */
  struct ConstData;
  friend struct ConstData;
  struct ConstData {
  private:
    const Uint32* m_data;
  public:
    ConstData();
    ConstData(const Uint32* data);
    ConstData& operator=(const Uint32* data);
    operator const Uint32*() const;
    ConstData& operator+=(size_t n);
    const AttributeHeader& ah() const;
    // non-const pointer can be cast to const pointer
    ConstData(Data data);
    ConstData& operator=(Data data);
  };

  // AttributeHeader size is assumed to be 1 word
  STATIC_CONST( AttributeHeaderSize = 1 );

  /*
   * Logical tuple address, "local key".  Identifies table tuples.
   */
  typedef Uint32 TupAddr;
  STATIC_CONST( NullTupAddr = (Uint32)-1 );

  /*
   * Physical tuple address in TUP.  Provides fast access to table tuple
   * or index node.  Valid within the db node and across timeslices.
   * Not valid between db nodes or across restarts.
   *
   * To avoid wasting an Uint16 the pageid is split in two.
   */
  struct TupLoc {
  private:
    Uint16 m_pageId1;           // page i-value (big-endian)
    Uint16 m_pageId2;
    Uint16 m_pageOffset;        // page offset in words
  public:
    TupLoc();
    TupLoc(Uint32 pageId, Uint16 pageOffset);
    Uint32 getPageId() const;
    void setPageId(Uint32 pageId);
    Uint32 getPageOffset() const;
    void setPageOffset(Uint32 pageOffset);
    bool operator==(const TupLoc& loc) const;
    bool operator!=(const TupLoc& loc) const;
  };

  /*
   * There is no const member NullTupLoc since the compiler may not be
   * able to optimize it to TupLoc() constants.  Instead null values are
   * constructed on the stack with TupLoc().
   */
#define NullTupLoc TupLoc()

  // tree definitions

  /*
   * Tree entry.  Points to a tuple in primary table via physical
   * address of "original" tuple and tuple version.
   *
   * ZTUP_VERSION_BITS must be 15 (or less).
   */
  struct TreeEnt;
  friend struct TreeEnt;
  struct TreeEnt {
    TupLoc m_tupLoc;            // address of original tuple
    unsigned m_tupVersion : 15; // version
    unsigned m_fragBit : 1;     // which duplicated table fragment
    TreeEnt();
    // methods
    bool eq(const TreeEnt ent) const;
    int cmp(const TreeEnt ent) const;
  };
  STATIC_CONST( TreeEntSize = sizeof(TreeEnt) >> 2 );
  static const TreeEnt NullTreeEnt;

  /*
   * Tree node has 1) fixed part 2) a prefix of index key data for min
   * entry 3) max and min entries 4) rest of entries 5) one extra entry
   * used as work space.
   *
   * struct TreeNode            part 1, size 6 words
   * min prefix                 part 2, size TreeHead::m_prefSize
   * max entry                  part 3
   * min entry                  part 3
   * rest of entries            part 4
   * work entry                 part 5
   *
   * There are 3 links to other nodes: left child, right child, parent.
   * Occupancy (number of entries) is at least 1 except temporarily when
   * a node is about to be removed.
   */
  struct TreeNode;
  friend struct TreeNode;
  struct TreeNode {
    TupLoc m_link[3];           // link to 0-left child 1-right child 2-parent
    unsigned m_side : 2;        // we are 0-left child 1-right child 2-root
    unsigned m_balance : 2;     // balance -1, 0, +1 plus 1 for Solaris CC
    unsigned pad1 : 4;
    Uint8 m_occup;              // current number of entries
    Uint32 m_nodeScan;          // list of scans at this node
    TreeNode();
  };
  STATIC_CONST( NodeHeadSize = sizeof(TreeNode) >> 2 );

  /*
   * Tree node "access size" was for an early version with signal
   * interface to TUP.  It is now used only to compute sizes.
   */
  enum AccSize {
    AccNone = 0,
    AccHead = 1,                // part 1
    AccPref = 2,                // parts 1-3
    AccFull = 3                 // parts 1-5
  };

  /*
   * Tree header.  There is one in each fragment.  Contains tree
   * parameters and address of root node.
   */
  struct TreeHead;
  friend struct TreeHead;
  struct TreeHead {
    Uint8 m_nodeSize;           // words in tree node
    Uint8 m_prefSize;           // words in min prefix
    Uint8 m_minOccup;           // min entries in internal node
    Uint8 m_maxOccup;           // max entries in node
    TupLoc m_root;              // root node
    TreeHead();
    // methods
    unsigned getSize(AccSize acc) const;
    Data getPref(TreeNode* node) const;
    TreeEnt* getEntList(TreeNode* node) const;
  };

  /*
   * Tree position.  Specifies node, position within node (from 0 to
   * m_occup), and whether the position is at an existing entry or
   * before one (if any).  Position m_occup points past the node and is
   * also represented by position 0 of next node.  Includes direction
   * used by scan.
   */
  struct TreePos;
  friend struct TreePos;
  struct TreePos {
    TupLoc m_loc;               // physical node address
    Uint16 m_pos;               // position 0 to m_occup
    Uint8 m_match;              // at an existing entry
    Uint8 m_dir;                // see scanNext()
    TreePos();
  };

  // packed metadata

  /*
   * Descriptor page.  The "hot" metadata for an index is stored as
   * a contiguous array of words on some page.
   */
  struct DescPage;
  friend struct DescPage;
  struct DescPage {
    Uint32 m_nextPage;
    Uint32 m_numFree;           // number of free words
    union {
    Uint32 m_data[DescPageSize];
    Uint32 nextPool;
    };
    DescPage();
  };
  typedef Ptr<DescPage> DescPagePtr;
  ArrayPool<DescPage> c_descPagePool;
  Uint32 c_descPageList;

  /*
   * Header for index metadata.  Size must be multiple of word size.
   */
  struct DescHead {
    unsigned m_indexId : 24;
    unsigned pad1 : 8;
  };
  STATIC_CONST( DescHeadSize = sizeof(DescHead) >> 2 );

  /*
   * Attribute metadata.  Size must be multiple of word size.
   *
   * Prefix comparison of char data must use strxfrm and binary
   * comparison.  The charset is currently unused.
   */
  struct DescAttr {
    Uint32 m_attrDesc;          // standard AttributeDescriptor
    Uint16 m_primaryAttrId;
    unsigned m_typeId : 6;
    unsigned m_charset : 10;
  };
  STATIC_CONST( DescAttrSize = sizeof(DescAttr) >> 2 );

  /*
   * Complete metadata for one index. The array of attributes has
   * variable size.
   */
  friend struct DescEnt;
  struct DescEnt {
    DescHead m_descHead;
    DescAttr m_descAttr[1];     // variable size data
  };

  // range scan
 
  /*
   * Scan bounds are stored in linked list of segments.
   */
  typedef DataBuffer<ScanBoundSegmentSize> ScanBound;
  typedef DataBuffer<ScanBoundSegmentSize>::ConstDataBufferIterator ScanBoundIterator;
  typedef DataBuffer<ScanBoundSegmentSize>::DataBufferPool ScanBoundPool;
  ScanBoundPool c_scanBoundPool;
 
  /*
   * Scan operation.
   *
   * Tuples are locked one at a time.  The current lock op is set to
   * RNIL as soon as the lock is obtained and passed to LQH.  We must
   * however remember all locks which LQH has not returned for unlocking
   * since they must be aborted by us when the scan is closed.
   *
   * Scan state describes the entry we are interested in.  There is
   * a separate lock wait flag.  It may be for current entry or it may
   * be for an entry we were moved away from.  In any case nothing
   * happens with current entry before lock wait flag is cleared.
   *
   * An unfinished scan is always linked to some tree node, and has
   * current position and direction (see comments at scanNext).  There
   * is also a copy of latest entry found.
   */
  struct ScanOp;
  friend struct ScanOp;
  struct ScanOp {
    enum {
      Undef = 0,
      First = 1,                // before first entry
      Current = 2,              // at current before locking
      Blocked = 3,              // at current waiting for ACC lock
      Locked = 4,               // at current and locked or no lock needed
      Next = 5,                 // looking for next extry
      Last = 6,                 // after last entry
      Aborting = 7,             // lock wait at scan close
      Invalid = 9               // cannot return REF to LQH currently
    };
    Uint16 m_state;
    Uint16 m_lockwait;
    Uint32 m_userPtr;           // scanptr.i in LQH
    Uint32 m_userRef;
    Uint32 m_tableId;
    Uint32 m_indexId;
    Uint32 m_fragId;
    Uint32 m_fragPtrI;
    Uint32 m_transId1;
    Uint32 m_transId2;
    Uint32 m_savePointId;
    // lock waited for or obtained and not yet passed to LQH
    Uint32 m_accLockOp;
    Uint8 m_readCommitted;      // no locking
    Uint8 m_lockMode;
    Uint8 m_descending;
    ScanBound m_boundMin;
    ScanBound m_boundMax;
    ScanBound* m_bound[2];      // pointers to above 2
    Uint16 m_boundCnt[2];       // number of bounds in each
    TreePos m_scanPos;          // position
    TreeEnt m_scanEnt;          // latest entry found
    Uint32 m_nodeScan;          // next scan at node (single-linked)
    union {
    Uint32 nextPool;
    Uint32 nextList;
    };
    Uint32 prevList;
    /*
     * Locks obtained and passed to LQH but not yet returned by LQH.
     * The max was increased from 16 to 992 (default 64).  Record max
     * ever used in this scan.  TODO fix quadratic behaviour
     */
    Uint32 m_maxAccLockOps;
    Uint32 m_accLockOps[MaxAccLockOps];
    ScanOp(ScanBoundPool& scanBoundPool);
  };
  typedef Ptr<ScanOp> ScanOpPtr;
  ArrayPool<ScanOp> c_scanOpPool;