MDEV-31487: Recovery or backup failure after innodb_undo_log_truncate=ON
recv_sys_t::parse(): For undo tablespace truncation mini-transactions,
remember the start_lsn instead of the end LSN. This is what we expect
after commit 461402a56432fa5cd0f6d53118ccce23081fca18 (MDEV-30479).
MDEV-31373 innodb_undo_log_truncate=ON recovery results in a corrupted undo log
recv_sys_t::apply(): When applying an undo log truncation operation,
invoke os_file_truncate() on space->recv_size, which must not be
less than the original truncated file size.
Alternatively, as pointed out by Thirunarayanan Balathandayuthapani,
we could assign space->size = t.pages, so that
fil_system_t::extend_to_recv_size() would extend the file back
to space->recv_size.
MDEV-31403: Server crashes in st_join_table::choose_best_splitting
The code in choose_best_splitting() assumed that the join prefix is
in join->positions[].
This is not necessarily the case. This function might be called when
the join prefix is in join->best_positions[], too.
Follow the approach from best_access_path(), which calls this function:
pass the current join prefix as an argument,
"const POSITION *join_positions" and use that.
MDEV-31234 fixup: Allow innodb_undo_log_truncate=ON after upgrade
trx_purge_truncate_history(): Relax a condition that would prevent
undo log truncation if the undo log tablespaces were "contaminated"
by the bug that commit e0084b9d315f10e3ceb578b65e144d751b208bf1 fixed.
That is, trx_purge_truncate_rseg_history() would have invoked
flst_remove() on TRX_RSEG_HISTORY but not reduced TRX_RSEG_HISTORY_SIZE.
To avoid any regression with normal operation, we implement this
fixup during slow shutdown only. The condition on the history list
being empty is necessary: without it, in the test
innodb.undo_truncate_recover there may be much fewer than the
expected 90,000 calls to row_purge() before the truncation.
That is, we would truncate the undo tablespace before actually having
processed all undo log records in it.
To truncate such "contaminated" or "bloated" undo log tablespaces
(when using innodb_undo_tablespaces=2 or more)
you can execute the following SQL:
BEGIN;INSERT mysql.innodb_table_stats VALUES('','',DEFAULT,0,0,0);ROLLBACK;
SET GLOBAL innodb_undo_log_truncate=ON, innodb_fast_shutdown=0;
SHUTDOWN;
The first line creates a dummy InnoDB transaction, to ensure that there
will be some history to be purged during shutdown and that the undo
tablespaces will be truncated.
trx_purge_truncate_rseg_history(): Add a parameter to specify if
the entire rollback segment is safe to be freed. If not, we may
still be able to invoke trx_undo_truncate_start() and free some pages.
MDEV-31234 InnoDB does not free UNDO after the fix of MDEV-30671
trx_purge_truncate_history(): Only call trx_purge_truncate_rseg_history()
if the rollback segment is safe to process. This will avoid leaking undo
log pages that are not yet ready to be processed. This fixes a regression
that was introduced in
commit 0de3be8cfdfc26f5c236eaefe12d03c7b4af22c8 (MDEV-30671).
trx_sys_t::any_active_transactions(): Separately count XA PREPARE
transactions.
srv_purge_should_exit(): Terminate slow shutdown if the history size
does not change and XA PREPARE transactions exist in the system.
This will avoid a hang of the test innodb.recovery_shutdown.
