diff options
Diffstat (limited to 'src/include/btmem.h')
| -rw-r--r-- | src/include/btmem.h | 110 |
1 files changed, 56 insertions, 54 deletions
diff --git a/src/include/btmem.h b/src/include/btmem.h index 9bd835f5d09..43c1a309d52 100644 --- a/src/include/btmem.h +++ b/src/include/btmem.h @@ -435,6 +435,19 @@ struct __wt_page_modify { }; /* + * WT_COL_RLE -- + * Variable-length column-store pages have an array of page entries with RLE + * counts greater than 1 when reading the page, so it's not necessary to walk + * the page counting records to find a specific entry. We can do a binary search + * in this array, then an offset calculation to find the cell. + */ +WT_PACKED_STRUCT_BEGIN(__wt_col_rle) + uint64_t recno; /* Record number of first repeat. */ + uint64_t rle; /* Repeat count. */ + uint32_t indx; /* Slot of entry in col_var. */ +WT_PACKED_STRUCT_END + +/* * WT_PAGE -- * The WT_PAGE structure describes the in-memory page information. */ @@ -515,53 +528,54 @@ struct __wt_page { } while (0) /* Row-store leaf page. */ - struct { - WT_ROW *d; /* Key/value pairs */ - uint32_t entries; /* Entries */ - } row; -#undef pg_row_d -#define pg_row_d u.row.d -#undef pg_row_entries -#define pg_row_entries u.row.entries + WT_ROW *row; /* Key/value pairs */ +#undef pg_row +#define pg_row u.row /* Fixed-length column-store leaf page. */ - struct { - uint8_t *bitf; /* Values */ - uint32_t entries; /* Entries */ - } col_fix; + uint8_t *fix_bitf; /* Values */ #undef pg_fix_bitf -#define pg_fix_bitf u.col_fix.bitf -#undef pg_fix_entries -#define pg_fix_entries u.col_fix.entries +#define pg_fix_bitf u.fix_bitf /* Variable-length column-store leaf page. */ struct { - WT_COL *d; /* Values */ + WT_COL *col_var; /* Values */ /* - * Variable-length column-store files maintain a list of - * RLE entries on the page so it's unnecessary to walk - * the page counting records to find a specific entry. + * Variable-length column-store pages have an array + * of page entries with RLE counts greater than 1 when + * reading the page, so it's not necessary to walk the + * page counting records to find a specific entry. We + * can do a binary search in this array, then an offset + * calculation to find the cell. + * + * It's a separate structure to keep the page structure + * as small as possible. */ - WT_COL_RLE *repeats; /* RLE array for lookups */ - uint32_t nrepeats; /* Number of repeat slots */ - - uint32_t entries; /* Entries */ + struct __wt_col_var_repeat { + uint32_t nrepeats; /* repeat slots */ + WT_COL_RLE repeats[0]; /* lookup RLE array */ + } *repeats; +#define WT_COL_VAR_REPEAT_SET(page) \ + ((page)->u.col_var.repeats != NULL) } col_var; -#undef pg_var_d -#define pg_var_d u.col_var.d +#undef pg_var +#define pg_var u.col_var.col_var #undef pg_var_repeats -#define pg_var_repeats u.col_var.repeats +#define pg_var_repeats u.col_var.repeats->repeats #undef pg_var_nrepeats -#define pg_var_nrepeats u.col_var.nrepeats -#undef pg_var_entries -#define pg_var_entries u.col_var.entries +#define pg_var_nrepeats u.col_var.repeats->nrepeats } u; /* - * The page's type and flags are positioned at the end of the WT_PAGE - * union, it reduces cache misses in the row-store search function. + * Page entries, type and flags are positioned at the end of the WT_PAGE + * union to reduce cache misses in the row-store search function. + * + * The entries field only applies to leaf pages, internal pages use the + * page-index entries instead. */ + uint32_t entries; /* Leaf page entries */ + #define WT_PAGE_IS_INTERNAL(page) \ ((page)->type == WT_PAGE_COL_INT || (page)->type == WT_PAGE_ROW_INT) #define WT_PAGE_INVALID 0 /* Invalid page */ @@ -618,8 +632,8 @@ struct __wt_page { #define WT_READGEN_START_VALUE 100 #define WT_READGEN_STEP 100 uint64_t read_gen; - /* The evict pass generation for the page */ - uint64_t evict_pass_gen; + + uint64_t evict_pass_gen; /* Eviction pass generation */ size_t memory_footprint; /* Memory attached to the page */ @@ -792,11 +806,11 @@ struct __wt_row { /* On-page key, on-page cell, or off-page WT_IKEY */ * Walk the entries of an in-memory row-store leaf page. */ #define WT_ROW_FOREACH(page, rip, i) \ - for ((i) = (page)->pg_row_entries, \ - (rip) = (page)->pg_row_d; (i) > 0; ++(rip), --(i)) + for ((i) = (page)->entries, \ + (rip) = (page)->pg_row; (i) > 0; ++(rip), --(i)) #define WT_ROW_FOREACH_REVERSE(page, rip, i) \ - for ((i) = (page)->pg_row_entries, \ - (rip) = (page)->pg_row_d + ((page)->pg_row_entries - 1); \ + for ((i) = (page)->entries, \ + (rip) = (page)->pg_row + ((page)->entries - 1); \ (i) > 0; --(rip), --(i)) /* @@ -804,7 +818,7 @@ struct __wt_row { /* On-page key, on-page cell, or off-page WT_IKEY */ * Return the 0-based array offset based on a WT_ROW reference. */ #define WT_ROW_SLOT(page, rip) \ - ((uint32_t)(((WT_ROW *)(rip)) - (page)->pg_row_d)) + ((uint32_t)(((WT_ROW *)(rip)) - (page)->pg_row)) /* * WT_COL -- @@ -829,18 +843,6 @@ struct __wt_col { }; /* - * WT_COL_RLE -- - * In variable-length column store leaf pages, we build an array of entries - * with RLE counts greater than 1 when reading the page. We can do a binary - * search in this array, then an offset calculation to find the cell. - */ -WT_PACKED_STRUCT_BEGIN(__wt_col_rle) - uint64_t recno; /* Record number of first repeat. */ - uint64_t rle; /* Repeat count. */ - uint32_t indx; /* Slot of entry in col_var.d */ -WT_PACKED_STRUCT_END - -/* * WT_COL_PTR, WT_COL_PTR_SET -- * Return/Set a pointer corresponding to the data offset. (If the item does * not exist on the page, return a NULL.) @@ -856,15 +858,15 @@ WT_PACKED_STRUCT_END * Walk the entries of variable-length column-store leaf page. */ #define WT_COL_FOREACH(page, cip, i) \ - for ((i) = (page)->pg_var_entries, \ - (cip) = (page)->pg_var_d; (i) > 0; ++(cip), --(i)) + for ((i) = (page)->entries, \ + (cip) = (page)->pg_var; (i) > 0; ++(cip), --(i)) /* * WT_COL_SLOT -- * Return the 0-based array offset based on a WT_COL reference. */ #define WT_COL_SLOT(page, cip) \ - ((uint32_t)(((WT_COL *)cip) - (page)->pg_var_d)) + ((uint32_t)(((WT_COL *)cip) - (page)->pg_var)) /* * WT_IKEY -- @@ -1041,7 +1043,7 @@ struct __wt_insert_head { #define WT_ROW_INSERT_SMALLEST(page) \ ((page)->modify == NULL || \ (page)->modify->mod_row_insert == NULL ? \ - NULL : (page)->modify->mod_row_insert[(page)->pg_row_entries]) + NULL : (page)->modify->mod_row_insert[(page)->entries]) /* * The column-store leaf page update lists are arrays of pointers to structures, |