The MDEV-25004 test innodb_fts.versioning is omitted because ever since
commit 685d958e38 InnoDB would not allow
writes to a database where the redo log file ib_logfile0 is missing.
to copy datafile
- Mariabackup fails to copy the undo log tablespace when it undergoes
truncation. So Mariabackup should detect the redo log which does
undo tablespace truncation and also backup should read the minimum
file size of the tablespace and ignore the error while reading.
- Throw error when innodb undo tablespace read failed, but backup
doesn't find the redo log for undo tablespace truncation
io_watching_thread(): Declare as a detachable thread, similar to
log_copying_thread().
stop_backup_threads(): Wait for both log_copying_thread and
io_watching_thread to clear their flags. Expect log_sys.mutex
to be held by the caller.
xtrabackup_backup_func(): Initialize log_copying_stop before
creating io_watching_thread. This prevents a race condition
where io_watching_thread() could wait on the condition variable
before it had been fully initialized. This race condition would
cause a hang in the GNU libc implementation of pthread_cond_destroy()
at the end of stop_backup_threads().
This race condition was introduced in
commit 38fd7b7d91 (MDEV-21452).
The variable was not really being used for anything. The parameters
innodb_read_io_threads, innodb_write_io_threads have replaced
innodb_file_io_threads.
- Mariabackup fails to open the undo tablespaces while applying delta
files to the corresponding data file. Mariabackup opens the
undo tablespaces first time in srv_undo_tablespaces_init() and does
tries to open the undo tablespaces in xtrabackup_apply_deltas() with
conflicting mode and leads to the failure.
- Mariabackup should close the undo tablespaces before applying
the incremental delta files.
os_file_read(): Merged with os_file_read_no_error_handling().
Crashing on a partial page read is as unhelpful as crashing on a
corrupted page read (commit 0b47c126e3).
Report the file name if it is available via IORequest.
Fix build failure in comp_err, if git is configured with default,
platform-specific EOL.
The error happens because comp_err is not prepared to handle extraneous
CR characters from errmgs-utf8.txt. Use fopen in text mode to fix.
trx_sys_t::undo_log_nonempty: Set to true if there are undo logs
to rollback and purge.
The algorithm for re-creating the undo tablespace when
trx_sys_t::undo_log_nonempty is disabled:
1) trx_sys_t::reset_page(): Reset the TRX_SYS page and assign all
rollback segment slots from 1..127 to FIL_NULL
2) Free the rollback segment header page of system tablespace
for the slots 1..127
3) Update the binlog and WSREP information in system tablespace
rollback segment header
Step (1), (2) and Step (3) should happen atomically within a
single mini-transaction.
4) srv_undo_delete_old_tablespaces(): Delete the old undo tablespaces
present in the undo log directory
5) Make checkpoint to get rid of old undo log tablespaces redo logs
6) Assign new start space id for the undo log tablespaces
7) Re-create the specified undo log tablespaces. InnoDB uses same
mtr for this one and step (6)
8) Make checkpoint again, so that server or mariabackup
can read the undo log tablespace page0 before applying
the redo logs
srv_undo_tablespaces_reinit(): Recreate the undo log tablespaces.
It does reset trx_sys page, delete the old undo tablespaces,
update the binlog offset, write set replication checkpoint
in system rollback segment page
trx_rseg_update_binlog_offset(): Added 2 new parameters to pass
binlog file name and binlog offset
trx_rseg_array_init(): Return error if the rollback segment
slot points to non-existent tablespace
srv_undo_tablespaces_init(): Added new parameter mtr
to initialize all undo tablespaces
trx_assign_rseg_low(): Allow the transaction to use the rollback
segment slots(1..127) even if InnoDB failed to change to the
requested innodb_undo_tablespaces=0
srv_start(): Override the user specified value of
innodb_undo_tablespaces variable with already existing actual
undo tablespaces
wf_incremental_process(): Detects whether TRX_SYS page has been
modified since last backup. If it is then incremental backup
fails and throws the information about taking full backup again
xb_assign_undo_space_start(): Removed the function. Because
undo001 has first undo space id value in page0
Added test case to test the scenario during startup and mariabackup
incremental process too.
Reviewed-by : Marko Mäkelä
Tested-by : Matthias Leich
mariadb-backup: Add the Boolean option --innodb-log-file-buffering
(default ON) to control whether the server's ib_logfile0 should be
accessed via the file system cache during --backup. We may be retrying
reads of the last log block very frequently, which may cause I/O stalls
when the file system cache is being bypassed.
This addresses a regression that was introduced in
commit 4c0cd953ab (MDEV-28766).
On some affected systems, it may make sense to additionally
SET GLOBAL innodb_log_file_buffering=OFF on the server for the
duration of making a backup.
