This saves 10 calls to pthread_mutex_lock when constructing the
initial OK packet for the default session_track_system_variables which
has 6 variables
Also added a testcase showing there's no need to worry about wildcard
session_track_system_variables as it causes construction of empty
string in the initial OK packet.
Lock LOCK_plugin only when the variable is a plugin variable.
Lock LOCK_global_system_variables only when the variable is a
global-only variable or a plugin variable.
Also fix lockless session value for Sys_var_multi_source_ulonglong.
This saves 54 calls to pthread_mutex_lock when constructing the
initial OK packet.
The added testcases do not show the lock savings. They are there to
improve coverage for the MDEV-31609 feature, in light of bugs like
MDEV-39207 and MDEV-39217.
MDEV-31751 changed the key from the sys_var pointer to its offset.
This was useful for non-plugin variable aliases, but not so much for
plugin variables which all have offset 0.
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
Change the type of my_hash_get_key to:
1) Return const
2) Change the context parameter to be const void*
Also fix casting in hash adjacent areas.
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
Values of all session tracking system variables will be sent in the
first ok packet upon connection after successful authentication.
Also updated mtr to print session track info on connection (h/t Sergei
Golubchik) so that we can write mtr tests for this change.
With session tracking on the tx_isolation of importance to
connector frameworks, its important that tracking of tx_isolation
does get informed if a user `set session transaction_isolation=X`
as the alias for tx_isolation.
Rather than just implement this for one variable alias, it
is implemented for all aliases.
To assist with this the key hash of session_tracker is now made up of
the offset, not the sys_var pointer.
The impacts of aliases are:
- If track one variable, its alias changes, you get a tracking
change on the variable you are monitoring.
- If you track two aliased variables of each other, changing
a variable will have a tracking events for only one of them.
Aliases of Sys_var_bit are not implemented, because we don't
have them, so would've been no way to verify that the new code works.
Post-Review edits by Sergei Golubchik <serg@mariadb.com>
Use < TL_FIRST_WRITE for determining a READ transaction.
Use TL_FIRST_WRITE as the relative operator replacing TL_WRITE_ALLOW_WRITE
as the minimium WRITE lock type.
session_track_system_variables and max_relay_log_size.
lock LOCK_global_system_variables around the get_one_variable() call
in the Session_sysvars_tracker::store_variable().
- Some of the bug fixes are backports from 10.5!
- The fix in innobase/fil/fil0fil.cc is just a backport to get less
error messages in mysqld.1.err when running with valgrind.
- Renamed HAVE_valgrind_or_MSAN to HAVE_valgrind
All changes (except one) is of type
thd->transaction. -> thd->transaction->
thd->transaction points by default to 'thd->default_transaction'
This allows us to 'easily' have multiple active transactions for a
THD object, like when reading data from the mysql.proc table
