diff options
Diffstat (limited to 'storage/innobase/dict/dict0stats.cc')
| -rw-r--r-- | storage/innobase/dict/dict0stats.cc | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/storage/innobase/dict/dict0stats.cc b/storage/innobase/dict/dict0stats.cc index 1c8e859c719..61810a88889 100644 --- a/storage/innobase/dict/dict0stats.cc +++ b/storage/innobase/dict/dict0stats.cc @@ -3332,16 +3332,18 @@ transient: return(DB_SUCCESS); } -/*********************************************************************//** -Removes the information for a particular index's stats from the persistent +/** Remove the information for a particular index's stats from the persistent storage if it exists and if there is data stored for this index. This function creates its own trx and commits it. -A note from Marko why we cannot edit user and sys_* tables in one trx: -marko: The problem is that ibuf merges should be disabled while we are -rolling back dict transactions. -marko: If ibuf merges are not disabled, we need to scan the *.ibd files. -But we shouldn't open *.ibd files before we have rolled back dict -transactions and opened the SYS_* records for the *.ibd files. + +We must modify system tables in a separate transaction in order to +adhere to the InnoDB design constraint that dict_sys.latch prevents +lock waits on system tables. If we modified system and user tables in +the same transaction, we should exclusively hold dict_sys.latch until +the transaction is committed, and effectively block other transactions +that will attempt to open any InnoDB tables. Because we have no +guarantee that user transactions will be committed fast, we cannot +afford to keep the system tables locked in a user transaction. @return DB_SUCCESS or error code */ dberr_t dict_stats_drop_index( |