mirror of
https://github.com/MariaDB/server.git
synced 2025-01-16 12:02:42 +01:00
ea37b14409
This is joint work with Thirunarayanan Balathandayuthapani.
The MDL interface between InnoDB and the rest of the server
(in storage/innobase/dict/dict0dict.cc and in include/)
is my work, while most everything else is Thiru's.
The collection of InnoDB persistent statistics and the
defragmentation were not refactored to use MDL. They will
keep relying on lower-level interlocking with
fil_check_pending_operations().
The purge of transaction history and the background operations on
fulltext indexes will use MDL. We will revert
commit 2c4844c9e7
(MDEV-17813) because thanks to MDL, purge cannot conflict
with DDL operations anymore. For a similar reason, we will remove
the MDEV-16222 test case from gcol.innodb_virtual_debug_purge.
Purge is essentially replacing all use of the global dict_sys.latch
with MDL. Purge will skip the undo log records for tables whose names
start with #sql-ib or #sql2. Theoretically, such tables might
be renamed back to visible table names if TRUNCATE fails to
create a new table, or the final rename in ALTER TABLE...ALGORITHM=COPY
fails. In that case, purge could permanently leave some garbage
in the table. Such garbage will be tolerated; the table would not
be considered corrupted.
To avoid repeated MDL releases and acquisitions,
trx_purge_attach_undo_recs() will sort undo log records by table_id,
and purge_node_t will keep the MDL and table handle open for multiple
successive undo log records.
get_purge_table(): A new accessor, used during the purge of
history for indexed virtual columns. This interface should ideally
not exist at all.
thd_mdl_context(): Accessor of THD::mdl_context.
Wrapped in a new thd_mdl_service.
dict_get_db_name_len(): Define inline.
dict_acquire_mdl_shared(): Acquire explicit shared MDL on a table name
if needed.
dict_table_open_on_id(): Return MDL_ticket, if requested.
dict_table_close(): Release MDL ticket, if requested.
dict_fts_index_syncing(), dict_index_t::index_fts_syncing: Remove.
row_drop_table_for_mysql() no longer needs to check these, because
MDL guarantees that a fulltext index sync will not be in progress
while MDL_EXCLUSIVE is protecting a DDL operation.
dict_table_t::parse_name(): Parse the table name for acquiring MDL.
purge_node_t::undo_recs: Change the type to std::list<trx_purge_rec_t*>
(different container, and storing also roll_ptr).
purge_node_t: Add mdl_ticket, last_table_id, purge_thd, mdl_hold_recs
for acquiring MDL and for keeping the table open across multiple
undo log records.
purge_vcol_info_t, row_purge_store_vsec_cur(), row_purge_restore_vsec_cur():
Remove. We will acquire the MDL earlier.
purge_sys_t::heap: Added, for reading undo log records.
fts_sync_during_ddl(): Invoked during ALGORITHM=INPLACE operations
to ensure that fts_sync_table() will not conflict with MDL_EXCLUSIVE.
Uses fts_t::sync_message for bookkeeping.
46 lines
1.3 KiB
C
46 lines
1.3 KiB
C
/* Copyright (c) 2019, MariaDB Corporation.
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; version 2 of the License.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
|
|
|
|
#pragma once
|
|
|
|
/**
|
|
@file include/mysql/service_thd_mdl.h
|
|
This service provides functions for plugins and storage engines to access
|
|
metadata locks.
|
|
*/
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
|
|
extern struct thd_mdl_service_st {
|
|
void *(*thd_mdl_context)(MYSQL_THD);
|
|
} *thd_mdl_service;
|
|
|
|
#ifdef MYSQL_DYNAMIC_PLUGIN
|
|
# define thd_mdl_context(_THD) thd_mdl_service->thd_mdl_context(_THD)
|
|
#else
|
|
/**
|
|
MDL_context accessor
|
|
@param thd the current session
|
|
@return pointer to thd->mdl_context
|
|
*/
|
|
void *thd_mdl_context(MYSQL_THD thd);
|
|
#endif
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|