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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 18:00:34 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 18:00:34 +0000 |
commit | 3f619478f796eddbba6e39502fe941b285dd97b1 (patch) | |
tree | e2c7b5777f728320e5b5542b6213fd3591ba51e2 /storage/myisam/rt_split.c | |
parent | Initial commit. (diff) | |
download | mariadb-3f619478f796eddbba6e39502fe941b285dd97b1.tar.xz mariadb-3f619478f796eddbba6e39502fe941b285dd97b1.zip |
Adding upstream version 1:10.11.6.upstream/1%10.11.6upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'storage/myisam/rt_split.c')
-rw-r--r-- | storage/myisam/rt_split.c | 348 |
1 files changed, 348 insertions, 0 deletions
diff --git a/storage/myisam/rt_split.c b/storage/myisam/rt_split.c new file mode 100644 index 00000000..1adcdb8e --- /dev/null +++ b/storage/myisam/rt_split.c @@ -0,0 +1,348 @@ +/* + Copyright (c) 2002, 2015, Oracle and/or its affiliates + + 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; version 2 of the License. + + 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */ + +#include "myisamdef.h" + +#ifdef HAVE_RTREE_KEYS + +#include "rt_index.h" +#include "rt_key.h" +#include "rt_mbr.h" + +typedef struct +{ + double square; + int n_node; + uchar *key; + double *coords; +} SplitStruct; + +inline static double *reserve_coords(double **d_buffer, int n_dim) +{ + double *coords = *d_buffer; + (*d_buffer) += n_dim * 2; + return coords; +} + +static void mbr_join(double *a, const double *b, int n_dim) +{ + double *end = a + n_dim * 2; + do + { + if (a[0] > b[0]) + a[0] = b[0]; + + if (a[1] < b[1]) + a[1] = b[1]; + + a += 2; + b += 2; + }while (a != end); +} + +/* +Counts the square of mbr which is a join of a and b +*/ +static double mbr_join_square(const double *a, const double *b, int n_dim) +{ + const double *end = a + n_dim * 2; + double square = 1.0; + do + { + square *= + ((a[1] < b[1]) ? b[1] : a[1]) - ((a[0] > b[0]) ? b[0] : a[0]); + + a += 2; + b += 2; + }while (a != end); + + /* Check if not finite (i.e. infinity or NaN) */ + if (!isfinite(square)) + square = DBL_MAX; + + return square; +} + +static double count_square(const double *a, int n_dim) +{ + const double *end = a + n_dim * 2; + double square = 1.0; + do + { + square *= a[1] - a[0]; + a += 2; + }while (a != end); + return square; +} + +inline static void copy_coords(double *dst, const double *src, int n_dim) +{ + memcpy(dst, src, sizeof(double) * (n_dim * 2)); +} + +/* +Select two nodes to collect group upon +*/ +static void pick_seeds(SplitStruct *node, int n_entries, + SplitStruct **seed_a, SplitStruct **seed_b, int n_dim) +{ + SplitStruct *cur1; + SplitStruct *lim1 = node + (n_entries - 1); + SplitStruct *cur2; + SplitStruct *lim2 = node + n_entries; + + double max_d = -DBL_MAX; + double d; + + *seed_a = node; + *seed_b = node + 1; + + for (cur1 = node; cur1 < lim1; ++cur1) + { + for (cur2=cur1 + 1; cur2 < lim2; ++cur2) + { + + d = mbr_join_square(cur1->coords, cur2->coords, n_dim) - cur1->square - + cur2->square; + if (d > max_d) + { + max_d = d; + *seed_a = cur1; + *seed_b = cur2; + } + } + } +} + +/* +Select next node and group where to add +*/ +static void pick_next(SplitStruct *node, int n_entries, double *g1, double *g2, + SplitStruct **choice, int *n_group, int n_dim) +{ + SplitStruct *cur = node; + SplitStruct *end = node + n_entries; + + double max_diff = -DBL_MAX; + + for (; cur<end; ++cur) + { + double diff; + double abs_diff; + + if (cur->n_node) + { + continue; + } + + diff = mbr_join_square(g1, cur->coords, n_dim) - + mbr_join_square(g2, cur->coords, n_dim); + + abs_diff = fabs(diff); + if (abs_diff > max_diff) + { + max_diff = abs_diff; + *n_group = 1 + (diff > 0); + *choice = cur; + } + } +} + +/* +Mark not-in-group entries as n_group +*/ +static void mark_all_entries(SplitStruct *node, int n_entries, int n_group) +{ + SplitStruct *cur = node; + SplitStruct *end = node + n_entries; + for (; cur<end; ++cur) + { + if (cur->n_node) + { + continue; + } + cur->n_node = n_group; + } +} + +static int split_rtree_node(SplitStruct *node, int n_entries, + int all_size, /* Total key's size */ + int key_size, + int min_size, /* Minimal group size */ + int size1, int size2 /* initial group sizes */, + double **d_buffer, int n_dim) +{ + SplitStruct *cur; + SplitStruct *UNINIT_VAR(a), *UNINIT_VAR(b); + double *g1 = reserve_coords(d_buffer, n_dim); + double *g2 = reserve_coords(d_buffer, n_dim); + SplitStruct *UNINIT_VAR(next); + int UNINIT_VAR(next_node); + int i; + SplitStruct *end = node + n_entries; + + if (all_size < min_size * 2) + { + return 1; + } + + cur = node; + for (; cur<end; ++cur) + { + cur->square = count_square(cur->coords, n_dim); + cur->n_node = 0; + } + + pick_seeds(node, n_entries, &a, &b, n_dim); + a->n_node = 1; + b->n_node = 2; + + + copy_coords(g1, a->coords, n_dim); + size1 += key_size; + copy_coords(g2, b->coords, n_dim); + size2 += key_size; + + + for (i=n_entries - 2; i>0; --i) + { + if (all_size - (size2 + key_size) < min_size) /* Can't write into group 2 */ + { + mark_all_entries(node, n_entries, 1); + break; + } + + if (all_size - (size1 + key_size) < min_size) /* Can't write into group 1 */ + { + mark_all_entries(node, n_entries, 2); + break; + } + + pick_next(node, n_entries, g1, g2, &next, &next_node, n_dim); + if (next_node == 1) + { + size1 += key_size; + mbr_join(g1, next->coords, n_dim); + } + else + { + size2 += key_size; + mbr_join(g2, next->coords, n_dim); + } + next->n_node = next_node; + } + + return 0; +} + +int rtree_split_page(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *page, uchar *key, + uint key_length, my_off_t *new_page_offs) +{ + int n1, n2; /* Number of items in groups */ + + SplitStruct *task; + SplitStruct *cur; + SplitStruct *stop; + double *coord_buf; + double *next_coord; + int n_dim; + uchar *source_cur, *cur1, *cur2; + uchar *new_page= info->buff; + int err_code= 0; + uint nod_flag= mi_test_if_nod(page); + uint full_length= key_length + (nod_flag ? nod_flag : + info->s->base.rec_reflength); + int max_keys= (mi_getint(page)-2) / (full_length); + DBUG_ENTER("rtree_split_page"); + DBUG_PRINT("rtree", ("splitting block")); + + n_dim = keyinfo->keysegs / 2; + + if (!(coord_buf= (double*) my_alloca(n_dim * 2 * sizeof(double) * + (max_keys + 1 + 4) + + sizeof(SplitStruct) * (max_keys + 1)))) + DBUG_RETURN(-1); /* purecov: inspected */ + + task= (SplitStruct *)(coord_buf + n_dim * 2 * (max_keys + 1 + 4)); + + next_coord = coord_buf; + + stop = task + max_keys; + source_cur = rt_PAGE_FIRST_KEY(page, nod_flag); + + for (cur = task; cur < stop; ++cur, source_cur = rt_PAGE_NEXT_KEY(source_cur, + key_length, nod_flag)) + { + cur->coords = reserve_coords(&next_coord, n_dim); + cur->key = source_cur; + rtree_d_mbr(keyinfo->seg, source_cur, key_length, cur->coords); + } + + cur->coords = reserve_coords(&next_coord, n_dim); + rtree_d_mbr(keyinfo->seg, key, key_length, cur->coords); + cur->key = key; + + if (split_rtree_node(task, max_keys + 1, + mi_getint(page) + full_length + 2, full_length, + rt_PAGE_MIN_SIZE(keyinfo->block_length), + 2, 2, &next_coord, n_dim)) + { + err_code = 1; + goto split_err; + } + + info->buff_used= 1; + stop = task + (max_keys + 1); + cur1 = rt_PAGE_FIRST_KEY(page, nod_flag); + cur2 = rt_PAGE_FIRST_KEY(new_page, nod_flag); + + n1= n2 = 0; + for (cur = task; cur < stop; ++cur) + { + uchar *to; + if (cur->n_node == 1) + { + to = cur1; + cur1 = rt_PAGE_NEXT_KEY(cur1, key_length, nod_flag); + ++n1; + } + else + { + to = cur2; + cur2 = rt_PAGE_NEXT_KEY(cur2, key_length, nod_flag); + ++n2; + } + if (to != cur->key) + memcpy(to - nod_flag, cur->key - nod_flag, full_length); + } + + mi_putint(page, 2 + n1 * full_length, nod_flag); + mi_putint(new_page, 2 + n2 * full_length, nod_flag); + + if ((*new_page_offs= _mi_new(info, keyinfo, DFLT_INIT_HITS)) == + HA_OFFSET_ERROR) + err_code= -1; + else + err_code= _mi_write_keypage(info, keyinfo, *new_page_offs, + DFLT_INIT_HITS, new_page); + DBUG_PRINT("rtree", ("split new block: %lu", (ulong) *new_page_offs)); + +split_err: + my_afree((uchar*) coord_buf); + DBUG_RETURN(err_code); +} + +#endif /*HAVE_RTREE_KEYS*/ |