release/src/router/mysql/storage/innodb_plugin/include/page0types.h

   1 /*****************************************************************************
   2
   3 Copyright (c) 1994, 2009, Innobase Oy. All Rights Reserved.
   4
   5 This program is free software; you can redistribute it and/or modify it under
   6 the terms of the GNU General Public License as published by the Free Software
   7 Foundation; version 2 of the License.
   8
   9 This program is distributed in the hope that it will be useful, but WITHOUT
  10 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  11 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
  12
  13 You should have received a copy of the GNU General Public License along with
  14 this program; if not, write to the Free Software Foundation, Inc.,
  15 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  16
  17 *****************************************************************************/
  18
  19 /**************************************************//**
  20 @file include/page0types.h
  21 Index page routines
  22
  23 Created 2/2/1994 Heikki Tuuri
  24 *******************************************************/
  25
  26 #ifndef page0types_h
  27 #define page0types_h
  28
  29 #include "univ.i"
  30 #include "dict0types.h"
  31 #include "mtr0types.h"
  32
  33 /** Eliminates a name collision on HP-UX */
  34 #define page_t     ib_page_t
  35 /** Type of the index page */
  36 typedef byte            page_t;
  37 /** Index page cursor */
  38 typedef struct page_cur_struct  page_cur_t;
  39
  40 /** Compressed index page */
  41 typedef byte                            page_zip_t;
  42 /** Compressed page descriptor */
  43 typedef struct page_zip_des_struct      page_zip_des_t;
  44
  45 /* The following definitions would better belong to page0zip.h,
  46 but we cannot include page0zip.h from rem0rec.ic, because
  47 page0*.h includes rem0rec.h and may include rem0rec.ic. */
  48
  49 /** Number of bits needed for representing different compressed page sizes */
  50 #define PAGE_ZIP_SSIZE_BITS 3
  51
  52 /** log2 of smallest compressed page size */
  53 #define PAGE_ZIP_MIN_SIZE_SHIFT 10
  54 /** Smallest compressed page size */
  55 #define PAGE_ZIP_MIN_SIZE       (1 << PAGE_ZIP_MIN_SIZE_SHIFT)
  56
  57 /** Number of supported compressed page sizes */
  58 #define PAGE_ZIP_NUM_SSIZE (UNIV_PAGE_SIZE_SHIFT - PAGE_ZIP_MIN_SIZE_SHIFT + 2)
  59 #if PAGE_ZIP_NUM_SSIZE > (1 << PAGE_ZIP_SSIZE_BITS)
  60 # error "PAGE_ZIP_NUM_SSIZE > (1 << PAGE_ZIP_SSIZE_BITS)"
  61 #endif
  62
  63 /** Compressed page descriptor */
  64 struct page_zip_des_struct
  65 {
  66         page_zip_t*     data;           /*!< compressed page data */
  67
  68 #ifdef UNIV_DEBUG
  69         unsigned        m_start:16;     /*!< start offset of modification log */
  70 #endif /* UNIV_DEBUG */
  71         unsigned        m_end:16;       /*!< end offset of modification log */
  72         unsigned        m_nonempty:1;   /*!< TRUE if the modification log
  73                                         is not empty */
  74         unsigned        n_blobs:12;     /*!< number of externally stored
  75                                         columns on the page; the maximum
  76                                         is 744 on a 16 KiB page */
  77         unsigned        ssize:PAGE_ZIP_SSIZE_BITS;
  78                                         /*!< 0 or compressed page size;
  79                                         the size in bytes is
  80                                         PAGE_ZIP_MIN_SIZE << (ssize - 1). */
  81 };
  82
  83 /** Compression statistics for a given page size */
  84 struct page_zip_stat_struct {
  85         /** Number of page compressions */
  86         ulint           compressed;
  87         /** Number of successful page compressions */
  88         ulint           compressed_ok;
  89         /** Number of page decompressions */
  90         ulint           decompressed;
  91         /** Duration of page compressions in microseconds */
  92         ib_uint64_t     compressed_usec;
  93         /** Duration of page decompressions in microseconds */
  94         ib_uint64_t     decompressed_usec;
  95 };
  96
  97 /** Compression statistics */
  98 typedef struct page_zip_stat_struct page_zip_stat_t;
  99
 100 /** Statistics on compression, indexed by page_zip_des_struct::ssize - 1 */
 101 extern page_zip_stat_t page_zip_stat[PAGE_ZIP_NUM_SSIZE - 1];
 102
 103 /**********************************************************************//**
 104 Write the "deleted" flag of a record on a compressed page.  The flag must
 105 already have been written on the uncompressed page. */
 106 UNIV_INTERN
 107 void
 108 page_zip_rec_set_deleted(
 109 /*=====================*/
 110         page_zip_des_t* page_zip,/*!< in/out: compressed page */
 111         const byte*     rec,    /*!< in: record on the uncompressed page */
 112         ulint           flag)   /*!< in: the deleted flag (nonzero=TRUE) */
 113         __attribute__((nonnull));
 114
 115 /**********************************************************************//**
 116 Write the "owned" flag of a record on a compressed page.  The n_owned field
 117 must already have been written on the uncompressed page. */
 118 UNIV_INTERN
 119 void
 120 page_zip_rec_set_owned(
 121 /*===================*/
 122         page_zip_des_t* page_zip,/*!< in/out: compressed page */
 123         const byte*     rec,    /*!< in: record on the uncompressed page */
 124         ulint           flag)   /*!< in: the owned flag (nonzero=TRUE) */
 125         __attribute__((nonnull));
 126
 127 /**********************************************************************//**
 128 Shift the dense page directory when a record is deleted. */
 129 UNIV_INTERN
 130 void
 131 page_zip_dir_delete(
 132 /*================*/
 133         page_zip_des_t* page_zip,/*!< in/out: compressed page */
 134         byte*           rec,    /*!< in: deleted record */
 135         dict_index_t*   index,  /*!< in: index of rec */
 136         const ulint*    offsets,/*!< in: rec_get_offsets(rec) */
 137         const byte*     free)   /*!< in: previous start of the free list */
 138         __attribute__((nonnull(1,2,3,4)));
 139
 140 /**********************************************************************//**
 141 Add a slot to the dense page directory. */
 142 UNIV_INTERN
 143 void
 144 page_zip_dir_add_slot(
 145 /*==================*/
 146         page_zip_des_t* page_zip,       /*!< in/out: compressed page */
 147         ulint           is_clustered)   /*!< in: nonzero for clustered index,
 148                                         zero for others */
 149         __attribute__((nonnull));
 150 #endif