database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-08-08 11:22:35 +03:00
Code Activity

Make the most important optimizer constants user variables

Browse Source 
Variables added:
- optimizer_index_block_copy_cost
- optimizer_key_copy_cost
- optimizer_key_next_find_cost
- optimizer_key_compare_cost
- optimizer_row_copy_cost
- optimizer_where_compare_cost

Some rename of defines was done to make the internal defines similar to
the visible ones:
TIME_FOR_COMPARE -> WHERE_COST; WHERE_COST was also "inverted" to be
a number between 0 and 1 that is multiply with accepted records
(similar to other optimizer variables).
TIME_FOR_COMPARE_IDX -> KEY_COMPARE_COST. This is also inverted,
similar to TIME_FOR_COMPARE.
TIME_FOR_COMPARE_ROWID -> ROWID_COMPARE_COST. This is also inverted,
similar to TIME_FOR_COMPARE.

All default costs are identical to what they where before this patch.

Other things:
- Compare factor in get_merge_buffers_cost() was inverted.
- Changed namespace to static in filesort_utils.cc
This commit is contained in:
Monty
2022-04-05 20:12:29 +03:00
committed by Sergei Petrunia
parent b6215b9b20
commit 5e651c9aea
28 changed files with 451 additions and 143 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
sql/sql_class.h
View File

@@ -692,6 +692,10 @@ typedef struct system_variables
ulonglong slave_skip_counter;
ulonglong max_relay_log_size;
double optimizer_index_block_copy_cost, optimizer_key_next_find_cost;
double optimizer_row_copy_cost, optimizer_key_copy_cost;
double optimizer_where_cost, optimizer_key_cmp_cost;
ha_rows select_limit;
ha_rows max_join_size;
ha_rows expensive_subquery_limit;
@@ -776,7 +780,7 @@ typedef struct system_variables
uint group_concat_max_len;
uint eq_range_index_dive_limit;
uint optimizer_cache_hit_ratio;
uint optimizer_cache_hit_ratio; // Stored in handler::optimizer_cache_cost
int max_user_connections;
/**