TEMPORARY PUSH: Changing all cost calculation to be given in ms10.7-selectivity-old

- Added tests/check_costs.pl, a tool to verify optimizer cost calculations.
  - Most costs has been found with this program. All steps to calculate
    the new costs are documented in Docs/optimizer.costs
- User optimizer_cost variables are given in usec (as individual
  costs can be very small). Internally they are stored in ms.
- Changed DISK_READ_COST (was DISK_SEEK_BASE_COST) from a hard disk cost
  (9 ms) to common SSD cost (400MB/sec).
- Changed the following handler functions to return IO_AND_CPU_COST.
  This makes it easy to apply different cost modifiers in ha_..time()
  functions for io and cpu costs.
  - scan_time()
  - rndpos_time()
  - keyread_time()
- Enhanched keyread_time() to calculate the full cost of reading of a set
  of keys with a given number of ranges and optionall number of blocks that
  need to be accessed.
- Removed read_time() as keyread_time() + rndpos_time() is the same thing.
- Added the following new optimizer_variables:
  - optimizer_scan_lookup_cost
  - optimizer_row_lookup_cost
  - optimizer_index_lookup_cost
  - optimizer_disk_read_cost
- Added include/my_tracker.h  ; Useful include file to quickly test costs
  of a function.
- Tuned sequence and heap engine costs (rest will be done in an updated
  commit)

1 files changed, 7 insertions, 3 deletions

diff --git a/sql/sql_class.h b/sql/sql_class.h
index 03c7fb6a847..b0bbf1c7230 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -683,9 +683,13 @@ typedef struct system_variables
   ulonglong slave_skip_counter;
   ulonglong max_relay_log_size;
 
-  double optimizer_index_block_copy_cost, optimizer_index_next_find_cost;
+  double optimizer_cache_hit_ratio;  // Stored in handler::optimizer_cache_cost
+  double optimizer_index_block_copy_cost;
+  double optimizer_row_next_find_cost, optimizer_index_next_find_cost;
   double optimizer_row_copy_cost, optimizer_key_copy_cost;
-  double optimizer_where_cmp_cost, optimizer_key_cmp_cost;
+  double optimizer_where_cost, optimizer_key_cmp_cost;
+  double optimizer_row_lookup_cost, optimizer_index_lookup_cost;
+  double optimizer_scan_lookup_cost,optimizer_disk_read_cost;
   double long_query_time_double, max_statement_time_double;
   double sample_percentage;
 
@@ -783,7 +787,6 @@ typedef struct system_variables
 
   uint group_concat_max_len;
   uint eq_range_index_dive_limit;
-  uint optimizer_cache_hit_ratio;  // Stored in handler::optimizer_cache_cost
   uint idle_transaction_timeout;
   uint idle_readonly_transaction_timeout;
   uint idle_write_transaction_timeout;
@@ -857,6 +860,7 @@ typedef struct system_variables
   uint    wsrep_sync_wait;
 
   vers_asof_timestamp_t vers_asof_timestamp;
+  uint64 optimizer_cost_version;
 } SV;
 
 /**