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MDEV-20950 Reduce size of record offsets

Browse source 
offset_t: this is a type which represents one record offset.
It's unsigned short int.

a lot of functions: replace ulint with offset_t

btr_pcur_restore_position_func(),
page_validate(),
row_ins_scan_sec_index_for_duplicate(),
row_upd_clust_rec_by_insert_inherit_func(),
row_vers_impl_x_locked_low(),
trx_undo_prev_version_build():
  allocate record offsets on the stack instead of waiting for rec_get_offsets()
  to allocate it from mem_heap_t. So, reducing  memory allocations.

RECORD_OFFSET, INDEX_OFFSET:
  now it's less convenient to store pointers in offset_t*
  array. One pointer occupies now several offset_t. And those constant are start
  indexes into array to places where to store pointer values

REC_OFFS_HEADER_SIZE: adjusted for the new reality

REC_OFFS_NORMAL_SIZE:
  increase size from 100 to 300 which means less heap allocations.
  And sizeof(offset_t[REC_OFFS_NORMAL_SIZE]) now is 600 bytes which
  is smaller than previous 800 bytes.

REC_OFFS_SEC_INDEX_SIZE: adjusted for the new reality

rem0rec.h, rem0rec.ic, rem0rec.cc:
  various arguments, return values and local variables types were changed to
  fix numerous integer conversions issues.

enum field_type_t:
  offset types concept was introduces which replaces old offset flags stuff.
  Like in earlier version, 2 upper bits are used to store offset type.
  And this enum represents those types.

REC_OFFS_SQL_NULL, REC_OFFS_MASK: removed

get_type(), set_type(), get_value(), combine():
  these are convenience functions to work with offsets and it's types

rec_offs_base()[0]:
  still uses an old scheme with flags REC_OFFS_COMPACT and REC_OFFS_EXTERNAL

rec_offs_base()[i]:
  these have type offset_t now. Two upper bits contains type.
This commit is contained in:
Eugene Kosov 2019-11-04 22:30:12 +03:00
commit f0aa073f2b
66 changed files with 792 additions and 745 deletions
Download patch file Download diff file Expand all files Collapse all files

9
storage/innobase/include/page0zip.h
View file

@ -47,6 +47,7 @@ Created June 2005 by Marko Makela
#endif /* !UNIV_INNOCHECKSUM */
#include "buf0types.h"
#include "rem0types.h"
#ifndef UNIV_INNOCHECKSUM
#include "dict0types.h"
@ -287,7 +288,7 @@ page_zip_write_rec(
page_zip_des_t* page_zip,/*!< in/out: compressed page */
const byte* rec, /*!< in: record being written */
dict_index_t* index, /*!< in: the index the record belongs to */
const ulint* offsets,/*!< in: rec_get_offsets(rec, index) */
const offset_t* offsets,/*!< in: rec_get_offsets(rec, index) */
ulint create) /*!< in: nonzero=insert, zero=update */
MY_ATTRIBUTE((nonnull));
@ -312,7 +313,7 @@ page_zip_write_blob_ptr(
const byte* rec, /*!< in/out: record whose data is being
written */
dict_index_t* index, /*!< in: index of the page */
const ulint* offsets,/*!< in: rec_get_offsets(rec, index) */
const offset_t* offsets,/*!< in: rec_get_offsets(rec, index) */
ulint n, /*!< in: column index */
mtr_t* mtr); /*!< in: mini-transaction handle,
or NULL if no logging is needed */
@ -346,7 +347,7 @@ page_zip_write_trx_id_and_roll_ptr(
/*===============================*/
page_zip_des_t* page_zip,/*!< in/out: compressed page */
byte* rec, /*!< in/out: record */
const ulint* offsets,/*!< in: rec_get_offsets(rec, index) */
const offset_t* offsets,/*!< in: rec_get_offsets(rec, index) */
ulint trx_id_col,/*!< in: column number of TRX_ID in rec */
trx_id_t trx_id, /*!< in: transaction identifier */
roll_ptr_t roll_ptr)/*!< in: roll_ptr */
@ -394,7 +395,7 @@ page_zip_dir_delete(
page_zip_des_t* page_zip, /*!< in/out: compressed page */
byte* rec, /*!< in: deleted record */
const dict_index_t* index, /*!< in: index of rec */
const ulint* offsets, /*!< in: rec_get_offsets(rec) */
const offset_t* offsets, /*!< in: rec_get_offsets(rec) */
const byte* free) /*!< in: previous start of
the free list */
MY_ATTRIBUTE((nonnull(1,2,3,4)));