This is a backport of the following fix from MySQL 5.7.23.
Some code refactoring has been omitted, and the test case has
been adapted to MariaDB.
commit 7a689acaa65e9d602575f7aa53fe36a64a07460f
Author: Krzysztof Kapuścik <krzysztof.kapuscik@oracle.com>
Date: Tue Mar 13 12:34:03 2018 +0100
Bug#27082268 Invalid FTS sync synchronization
The fix closes two issues:
Bug #27082268 - INNODB: FAILING ASSERTION: SYM_NODE->TABLE != NULL DURING FTS SYNC
Bug #27095935 - DEADLOCK BETWEEN FTS_DROP_INDEX AND FTS_OPTIMIZE_SYNC_TABLE
Both issues were related to a FTS cache sync being done during
operations that perfomed DDL actions on internal FTS tables
(ALTER TABLE, TRUNCATE). In some cases the FTS tables and/or
internal cache structures could get removed while still being
used to perform FTS synchronization leading to crashes. In other
the sync operations could not get finishes as it was waiting for
dict lock which was taken by thread waiting for the background
sync to be finished.
The changes done includes:
- Stopping background operations during ALTER TABLE and TRUNCATE.
- Removal of unused code in FTS.
- Cleanup of FTS sync related code to make it more readable and
easier to maintain.
RB#18262
fts_create_doc_id(): Remove.
row_mysql_convert_row_to_innobase(): Implement the logic of
fts_create_doc_id(). Reuse a buffer for the hidden FTS_DOC_ID.
row_get_prebuilt_insert_row(): Allocate a buffer for the hidden
FTS_DOC_ID at the end of prebuilt->ins_upd_rec_buff.
crashes server
This bug is the result of merging the Oracle MySQL follow-up fix
BUG#22963169 MYSQL CRASHES ON CREATE FULLTEXT INDEX
without merging the base bug fix:
Bug#79475 Insert a token of 84 4-bytes chars into fts index causes
server crash.
Unlike the above mentioned fixes in MySQL, our fix will not change
the storage format of fulltext indexes in InnoDB or XtraDB
when a character encoding with mbmaxlen=2 or mbmaxlen=3
and the length of a word is between 128 and 84*mbmaxlen bytes.
The Oracle fix would allocate 2 length bytes for these cases.
Compatibility with other MySQL and MariaDB releases is ensured by
persisting the used maximum length in the SYS_COLUMNS table in the
InnoDB data dictionary.
This fix also removes some unnecessary strcmp() calls when checking
for the legacy default collation my_charset_latin1
(my_charset_latin1.name=="latin1_swedish_ci").
fts_create_one_index_table(): Store the actual length in bytes.
This metadata will be written to the SYS_COLUMNS table.
fts_zip_initialize(): Initialize only the first byte of the buffer.
Actually the code should not even care about this first byte, because
the length is set as 0.
FTX_MAX_WORD_LEN: Define as HA_FT_MAXCHARLEN * 4 aka 336 bytes,
not as 254 bytes.
row_merge_create_fts_sort_index(): Set the actual maximum length of the
column in bytes, similar to fts_create_one_index_table().
row_merge_fts_doc_tokenize(): Remove the redundant parameter word_dtype.
Use the actual maximum length of the column. Calculate the extra_size
in the same way as row_merge_buf_encode() does.
