The functions fil_file_readdir_next_file(), os_file_opendir(),
os_file_closedir() became dead code in the server in MariaDB 10.4.0
with commit 09af00cbde (the removal of
the crash recovery logic for the TRUNCATE TABLE implementation that
was replaced in MDEV-13564).
os_file_opendir(), os_file_closedir(): Define as macros.
dict_table_rename_in_cache(): Use strcpy() instead of strncpy(),
because they are known to be equivalent in this case (the length
of old_name was already validated).
mariabackup: Invoke strncpy() with one less than the buffer size,
and explicitly add NUL as the last byte of the buffer.
It's a micro optimization. On most platforms CPUs has instructions to
compare with 0 fast. DB_SUCCESS is the most popular outcome of functions
and this patch optimized code like (err == DB_SUCCESS)
BtrBulk::finish(): bogus assertion fixed
fil_node_t::read_page0(): corrected usage of os_file_read()
que_eval_sql(): bugus assertion removed. Apparently it checked that
the field was assigned after having been zero-initialized at
object creation.
It turns out that the return type of os_file_read_func() was changed
in mysql/mysql-server@98909cefbc (MySQL 5.7)
from ibool to dberr_t. The reviewer (if there was any) failed to
point out that because of future merges, it could be a bad idea to
change the return type of a function without changing the function name.
This change was applied to MariaDB 10.2.2 in
commit 2e814d4702 but the
MariaDB-specific code was not fully adjusted accordingly,
e.g. in fil_node_open_file(). Essentially, code like
!os_file_read(...) became dead code in MariaDB and later
in Mariabackup 10.2, and we could be dealing with an uninitialized
buffer after a failed page read.
Bind more InnoDB parameters directly to MYSQL_SYSVAR and
remove "shadow variables".
innodb_change_buffering: Declare as ENUM, not STRING.
innodb_flush_method: Declare as ENUM, not STRING.
innodb_log_buffer_size: Bind directly to srv_log_buffer_size,
without rounding it to a multiple of innodb_page_size.
LOG_BUFFER_SIZE: Remove.
SysTablespace::normalize_size(): Renamed from normalize().
innodb_init_params(): A new function to initialize and validate
InnoDB startup parameters.
innodb_init(): Renamed from innobase_init(). Invoke innodb_init_params()
before actually trying to start up InnoDB.
srv_start(bool): Renamed from innobase_start_or_create_for_mysql().
Added the input parameter create_new_db.
SRV_ALL_O_DIRECT_FSYNC: Define only for _WIN32.
xb_normalize_init_values(): Merge to innodb_init_param().
InnoDB I/O and buffer pool interfaces and the redo log format
have been changed between MariaDB 10.1 and 10.2, and the backup
code has to be adjusted accordingly.
The code has been simplified, and many memory leaks have been fixed.
Instead of the file name xtrabackup_logfile, the file name ib_logfile0
is being used for the copy of the redo log. Unnecessary InnoDB startup and
shutdown and some unnecessary threads have been removed.
Some help was provided by Vladislav Vaintroub.
Parameters have been cleaned up and aligned with those of MariaDB 10.2.
The --dbug option has been added, so that in debug builds,
--dbug=d,ib_log can be specified to enable diagnostic messages
for processing redo log entries.
By default, innodb_doublewrite=OFF, so that --prepare works faster.
If more crash-safety for --prepare is needed, double buffering
can be enabled.
The parameter innodb_log_checksums=OFF can be used to ignore redo log
checksums in --backup.
Some messages have been cleaned up.
Unless --export is specified, Mariabackup will not deal with undo log.
The InnoDB mini-transaction redo log is not only about user-level
transactions; it is actually about mini-transactions. To avoid confusion,
call it the redo log, not transaction log.
We disable any undo log processing in --prepare.
Because MariaDB 10.2 supports indexed virtual columns, the
undo log processing would need to be able to evaluate virtual column
expressions. To reduce the amount of code dependencies, we will not
process any undo log in prepare.
This means that the --export option must be disabled for now.
This also means that the following options are redundant
and have been removed:
xtrabackup --apply-log-only
innobackupex --redo-only
In addition to disabling any undo log processing, we will disable any
further changes to data pages during --prepare, including the change
buffer merge. This means that restoring incremental backups should
reliably work even when change buffering is being used on the server.
Because of this, preparing a backup will not generate any further
redo log, and the redo log file can be safely deleted. (If the
--export option is enabled in the future, it must generate redo log
when processing undo logs and buffered changes.)
In --prepare, we cannot easily know if a partial backup was used,
especially when restoring a series of incremental backups. So, we
simply warn about any missing files, and ignore the redo log for them.
FIXME: Enable the --export option.
FIXME: Improve the handling of the MLOG_INDEX_LOAD record, and write
a test that initiates a backup while an ALGORITHM=INPLACE operation
is creating indexes or rebuilding a table. An error should be detected
when preparing the backup.
FIXME: In --incremental --prepare, xtrabackup_apply_delta() should
ensure that if FSP_SIZE is modified, the file size will be adjusted
accordingly.
Significantly reduce the amount of InnoDB, XtraDB and Mariabackup
code changes by defining pfs_os_file_t as something that is
transparently compatible with os_file_t.
