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.
These changes are comparable to Percona's modifications in innodb in the
Percona Xtrabackup repository.
- If functions are used in backup as well as in innodb, make them non-static.
- Define IS_XTRABACKUP() macro for special handling of innodb running
inside backup.
- Extend some functions for backup.
fil_space_for_table_exists_in_mem() gets additional parameter
'remove_from_data_dict_if_does_not_exist', for partial backups
fil_load_single_table_tablespaces() gets an optional parameter predicate
which tells whether to load tablespace based on database or table name,
also for partial backups.
srv_undo_tablespaces_init() gets an optional parameter 'backup_mode'
- Allow single redo log file (for backup "prepare")
- Do not read doublewrite buffer pages in backup, they are outdated
- Add function fil_remove_invalid_table_from_data_dict(), to remove non-existing
tables from data dictionary in case of partial backups.
- On Windows, fix file share modes when opening tablespaces,
to allow mariabackup to read tablespaces while server is online.
- Avoid access to THDVARs in backup, because innodb plugin is not loaded,
and THDVAR would crash in this case.
Allow 64-bit atomic operations on 32-bit systems,
only relying on HAVE_ATOMIC_BUILTINS_64, disregarding
the width of the register file.
Define UNIV_WORD_SIZE correctly on all systems, including Windows.
In MariaDB 10.0 and 10.1, it was incorrectly defined as 4 on
64-bit Windows.
Define HAVE_ATOMIC_BUILTINS_64 on Windows
(64-bit atomics are available on both 32-bit and 64-bit Windows
platforms; the operations were unnecessarily disabled even on
64-bit Windows).
MONITOR_OS_PENDING_READS, MONITOR_OS_PENDING_WRITES: Enable by default.
os_file_n_pending_preads, os_file_n_pending_pwrites,
os_n_pending_reads, os_n_pending_writes: Remove.
Use the monitor counters instead.
os_file_count_mutex: Remove. On a system that does not support
64-bit atomics, monitor_mutex will be used instead.
Also, implement MDEV-11027 a little differently from 5.5 and 10.0:
recv_apply_hashed_log_recs(): Change the return type back to void
(DB_SUCCESS was always returned).
Report progress also via systemd using sd_notifyf().
The function posix_fallocate() as well as the Linux system call
fallocate() can return EINTR when the operation was interrupted
by a signal. In that case, keep retrying the operation, except
if InnoDB shutdown has been initiated.
If page_compression (introduced in MariaDB Server 10.1) is enabled,
the logical action is to not preallocate space to the data files,
but to only logically extend the files with zeroes.
fil_create_new_single_table_tablespace(): Create smaller files for
ROW_FORMAT=COMPRESSED tables, but adhere to the minimum file size of
4*innodb_page_size.
fil_space_extend_must_retry(), os_file_set_size(): On Windows,
use SetFileInformationByHandle() and FILE_END_OF_FILE_INFO,
which depends on bumping _WIN32_WINNT to 0x0600.
FIXME: The files are not yet set up as sparse, so
this will currently end up physically extending (preallocating)
the files, wasting storage for unused pages.
os_file_set_size(): Add the parameter "bool sparse=false" to declare
that the file is to be extended logically, instead of being preallocated.
The only caller with sparse=true is
fil_create_new_single_table_tablespace().
(The system tablespace cannot be created with page_compression.)
fil_space_extend_must_retry(), os_file_set_size(): Outside Windows,
use ftruncate() to extend files that are supposed to be sparse.
On systems where ftruncate() is limited to files less than 4GiB
(if there are any), fil_space_extend_must_retry() retains the
old logic of physically extending the file.
a large memory buffer on Windows
fil_extend_space_to_desired_size(), os_file_set_size(): Use calloc()
for memory allocation, and handle failures. Properly check the return
status of posix_fallocate(), and pass the correct arguments to
posix_fallocate().
On Windows, instead of extending the file by at most 1 megabyte at a time,
write a zero-filled page at the end of the file.
According to the Microsoft blog post
https://blogs.msdn.microsoft.com/oldnewthing/20110922-00/?p=9573
this will physically extend the file by writing zero bytes.
(InnoDB never uses DeviceIoControl() to set the file sparse.)
I tested that the file extension works properly with a multi-file
system tablespace, both with --innodb-use-fallocate and
--skip-innodb-use-fallocate (the default):
./mtr \
--mysqld=--innodb-use-fallocate \
--mysqld=--innodb-autoextend-increment=1 \
--mysqld=--innodb-data-file-path='ibdata1:5M;ibdata2:5M:autoextend' \
--parallel=auto --force --retry=0 --suite=innodb &
ls -lsh mysql-test/var/*/mysqld.1/data/ibdata2
(several samples while running the test)
The function trx_purge_stop() was calling os_event_reset(purge_sys->event)
before calling rw_lock_x_lock(&purge_sys->latch). The os_event_set()
call in srv_purge_coordinator_suspend() is protected by that X-latch.
It would seem a good idea to consistently protect both os_event_set()
and os_event_reset() calls with a common mutex or rw-lock in those
cases where os_event_set() and os_event_reset() are used
like condition variables, tied to changes of shared state.
For each os_event_t, we try to document the mutex or rw-lock that is
being used. For some events, frequent calls to os_event_set() seem to
try to avoid hangs. Some events are never waited for infinitely, only
timed waits, and os_event_set() is used for early termination of these
waits.
os_aio_simulated_put_read_threads_to_sleep(): Define as a null macro
on other systems than Windows. TODO: remove this altogether and disable
innodb_use_native_aio on Windows.
os_aio_segment_wait_events[]: Initialize only if innodb_use_native_aio=0.
Replace all exit() calls in InnoDB with abort() [possibly via ut_a()].
Calling exit() in a multi-threaded program is problematic also for
the reason that other threads could see corrupted data structures
while some data structures are being cleaned up by atexit() handlers
or similar.
In the long term, all these calls should be replaced with something
that returns an error all the way up the call stack.
The changes are deliberately kept minimal
- some functions are made global instead of static (they will be used in
xtrabackup later on)
- functions got additional parameter, deliberately unused for now :
fil_load_single_tablespaces
srv_undo_tablespaces_init
- Global variables added, also unused for now :
srv_archive_recovery
srv_archive_recovery_limit_lsn
srv_apply_log_only
srv_backup_mode
srv_close_files
- To make xtrabackup link with sql.lib on Windows, added some missing
source files to sql.lib
- Fixed os_thread_ret_t to be DWORD on Windows
Problem was that link file (.isl) is also opened using O_DIRECT
mode and if this fails the whole create table fails on internal
error.
Fixed by not using O_DIRECT on link files as they are used only
on create table and startup and do not contain real data.
O_DIRECT failures are successfully ignored for data files
if O_DIRECT is not supported by file system on used
data directory.
