1. dbug state is now local to a thread
2. new macros: DBUG_EXPLAIN, DBUG_EXPLAIN_INITIAL,
DBUG_SET, DBUG_SET_INITIAL, DBUG_EVALUATE, DBUG_EVALUATE_IF
3. macros are do{}while(0) wrapped
4. incremental modifications to the dbug state (e.g. "+d,info:-t")
5. dbug code cleanup, style fixes
6. _db_on_ and DEBUGGER_ON/OFF removed
7. rest of MySQL code fixed because of 3 (missing ;) and 6
8. dbug manual updated
9. server variable @@debug (global and local) to control dbug from SQL!
a. -#T to print timestamps in the log
when high concurrency": remove HASH::current_record and make it
an external search parameter, so that it can not be the cause of a
race condition under high concurrent load.
The bug was in a race condition in table_hash_search,
when column_priv_hash.current_record was overwritten simultaneously
by multiple threads, causing the search for a suitable grant record
to fail.
No test case as the bug is repeatable only under concurrent load.
The table opening process now works the following way:
- Create common TABLE_SHARE object
- Read the .frm file and unpack it into the TABLE_SHARE object
- Create a TABLE object based on the information in the TABLE_SHARE
object and open a handler to the table object
Other noteworthy changes:
- In TABLE_SHARE the most common strings are now LEX_STRING's
- Better error message when table is not found
- Variable table_cache is now renamed 'table_open_cache'
- New variable 'table_definition_cache' that is the number of table defintions that will be cached
- strxnmov() calls are now fixed to avoid overflows
- strxnmov() will now always add one end \0 to result
- engine objects are now created with a TABLE_SHARE object instead of a TABLE object.
- After creating a field object one must call field->init(table) before using it
- For a busy system this change will give you:
- Less memory usage for table object
- Faster opening of tables (if it's has been in use or is in table definition cache)
- Allow you to cache many table definitions objects
- Faster drop of table
For LOCK view is opened but not prepared thus leaving 'table' field set to
NULL. invalidate_locked_for_write() wasn't checking that and call to
invalidate_table(NULL) crashes server.
To invalidate_locked_for_write() added check that ensures that table is
completely opened.
Changed defaults option --instance to --defaults-group-suffix
Changed option handling to allow --defaults-file, --defaults-extra-file and --defaults-group-suffix to be given in any order
Changed MYSQL_INSTANCE to MYSQL_GROUP_SUFFIX
mysql_print_defaults now understands --defaults-group-suffix
Remove usage of my_tempnam() (not safe function)
if( -> if ( and while( to while (
Windows to call CreateFileMapping() with correct arguments, and
propogating the introduction of query_id_t to everywhere query ids are
passed around. (Bug #8826)