granicus.if.org Git - postgresql/blob - src/include/storage/freespace.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * freespace.h
   4  *        POSTGRES free space map for quickly finding free space in relations
   5  *
   6  *
   7  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  * $Id: freespace.h,v 1.12 2003/08/04 02:40:14 momjian Exp $
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #ifndef FREESPACE_H_
  15 #define FREESPACE_H_
  16
  17 #include "storage/block.h"
  18 #include "storage/relfilenode.h"
  19
  20
  21 /*
  22  * exported types
  23  */
  24 typedef struct PageFreeSpaceInfo
  25 {
  26         BlockNumber blkno;                      /* which page in relation */
  27         Size            avail;                  /* space available on this page */
  28 }       PageFreeSpaceInfo;
  29
  30
  31 /* GUC variables */
  32 extern int      MaxFSMRelations;
  33 extern int      MaxFSMPages;
  34
  35
  36 /*
  37  * function prototypes
  38  */
  39 extern void InitFreeSpaceMap(void);
  40 extern int      FreeSpaceShmemSize(void);
  41
  42 extern BlockNumber GetPageWithFreeSpace(RelFileNode *rel, Size spaceNeeded);
  43 extern BlockNumber RecordAndGetPageWithFreeSpace(RelFileNode *rel,
  44                                                           BlockNumber oldPage,
  45                                                           Size oldSpaceAvail,
  46                                                           Size spaceNeeded);
  47 extern Size GetAvgFSMRequestSize(RelFileNode *rel);
  48 extern void RecordRelationFreeSpace(RelFileNode *rel,
  49                                                 int nPages,
  50                                                 PageFreeSpaceInfo * pageSpaces);
  51
  52 extern BlockNumber GetFreeIndexPage(RelFileNode *rel);
  53 extern void RecordIndexFreeSpace(RelFileNode *rel,
  54                                          int nPages,
  55                                          BlockNumber *pages);
  56
  57 extern void FreeSpaceMapTruncateRel(RelFileNode *rel, BlockNumber nblocks);
  58 extern void FreeSpaceMapForgetRel(RelFileNode *rel);
  59 extern void FreeSpaceMapForgetDatabase(Oid dbid);
  60
  61 extern void PrintFreeSpaceMapStatistics(int elevel);
  62
  63 extern void DumpFreeSpaceMap(void);
  64 extern void LoadFreeSpaceMap(void);
  65
  66 #ifdef FREESPACE_DEBUG
  67 extern void DumpFreeSpace(void);
  68 #endif
  69
  70 #endif   /* FREESPACE_H */