Hi, Sergey! Looks pretty much ok. See few comments/questions below.
On Oct 24, Sergey Vojtovich wrote: > ------------------------------------------------------------ > revno: 3807 > revision-id: [email protected] > parent: [email protected] > committer: Sergey Vojtovich <[email protected]> > branch nick: 10.0 > timestamp: Tue 2013-08-27 16:12:33 +0400 > message: > MDEV-4956 - Reduce usage of LOCK_open: TABLE_SHARE::tdc.used_tables > > - tc_acquire_table and tc_release_table do not access > TABLE_SHARE::tdc.used_tables anymore ok > - in tc_acquire_table(): release LOCK_tdc after we relase LOCK_open > (saves a few CPU cycles in critical section) This is a bit counter-intuitive. Your change is to hold the lock more than necessary. Does it give a measurable performance improvement? > - in tc_release_table(): if we reached table cache threshold, evict > to-be-released table without moving it to unused_tables. unused_tables > must be empty at this point (added assertion). Why unused_tables must be empty at this point? > === modified file 'sql/sql_base.cc' > --- a/sql/sql_base.cc 2013-08-14 08:48:50 +0000 > +++ b/sql/sql_base.cc 2013-08-27 12:12:33 +0000 > @@ -370,7 +372,7 @@ void free_io_cache(TABLE *table) > > void kill_delayed_threads_for_table(TABLE_SHARE *share) > { > - TABLE_SHARE::TABLE_list::Iterator it(share->tdc.used_tables); > + TABLE_SHARE::All_share_tables_list::Iterator it(share->tdc.all_tables); In this function, I'd suggest to add some flag to be able to skip the mutex and the loop altogether - as in the absolute majority of cases there will be no delayed insert thread to kill. Either use a global flag to know if there's a delayed thread running, or create a per-share flag. > TABLE *tab; > Regards, Sergei _______________________________________________ Mailing list: https://launchpad.net/~maria-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~maria-developers More help : https://help.launchpad.net/ListHelp
