Merge MDEV-7847 and MDEV-7882 into 10.0.

Conflicts:
	mysql-test/suite/rpl/r/rpl_parallel.result
	sql/rpl_parallel.cc

mysql-test/suite/rpl/r/rpl_parallel.result

@@ -1264,11 +1264,297 @@ a
 include/stop_slave.inc
 SET GLOBAL slave_parallel_mode='conservative';
 include/start_slave.inc
+*** MDEV-7847: "Slave worker thread retried transaction 10 time(s) in vain, giving up", followed by replication hanging ***
+*** MDEV-7882: Excessive transaction retry in parallel replication ***
+CREATE TABLE t7 (a int PRIMARY KEY, b INT) ENGINE=InnoDB;
+CREATE TABLE t8 (a int PRIMARY KEY, b INT) ENGINE=InnoDB;
+include/stop_slave.inc
+SET GLOBAL slave_parallel_threads=40;
+SELECT @old_retries:=@@GLOBAL.slave_transaction_retries;
+@old_retries:=@@GLOBAL.slave_transaction_retries
+10
+SET GLOBAL slave_transaction_retries= 5;
+INSERT INTO t7 VALUES (1,1), (2,2), (3,3), (4,4), (5,5);
+SET @old_dbug= @@SESSION.debug_dbug;
+SET @commit_id= 42;
+SET SESSION debug_dbug="+d,binlog_force_commit_id";
+INSERT INTO t8 VALUES (1,1);
+INSERT INTO t8 VALUES (2,2);
+INSERT INTO t8 VALUES (3,3);
+INSERT INTO t8 VALUES (4,4);
+INSERT INTO t8 VALUES (5,5);
+INSERT INTO t8 VALUES (6,6);
+INSERT INTO t8 VALUES (7,7);
+INSERT INTO t8 VALUES (8,8);
+UPDATE t7 SET b=9 WHERE a=3;
+UPDATE t7 SET b=10 WHERE a=3;
+UPDATE t7 SET b=11 WHERE a=3;
+INSERT INTO t8 VALUES (12,12);
+INSERT INTO t8 VALUES (13,13);
+UPDATE t7 SET b=14 WHERE a=3;
+UPDATE t7 SET b=15 WHERE a=3;
+INSERT INTO t8 VALUES (16,16);
+UPDATE t7 SET b=17 WHERE a=3;
+INSERT INTO t8 VALUES (18,18);
+INSERT INTO t8 VALUES (19,19);
+UPDATE t7 SET b=20 WHERE a=3;
+INSERT INTO t8 VALUES (21,21);
+UPDATE t7 SET b=22 WHERE a=3;
+INSERT INTO t8 VALUES (23,24);
+INSERT INTO t8 VALUES (24,24);
+UPDATE t7 SET b=25 WHERE a=3;
+INSERT INTO t8 VALUES (26,26);
+UPDATE t7 SET b=27 WHERE a=3;
+BEGIN;
+INSERT INTO t8 VALUES (28,28);
+INSERT INTO t8 VALUES (29,28), (30,28);
+INSERT INTO t8 VALUES (31,28);
+INSERT INTO t8 VALUES (32,28);
+INSERT INTO t8 VALUES (33,28);
+INSERT INTO t8 VALUES (34,28);
+INSERT INTO t8 VALUES (35,28);
+INSERT INTO t8 VALUES (36,28);
+INSERT INTO t8 VALUES (37,28);
+INSERT INTO t8 VALUES (38,28);
+INSERT INTO t8 VALUES (39,28);
+INSERT INTO t8 VALUES (40,28);
+INSERT INTO t8 VALUES (41,28);
+INSERT INTO t8 VALUES (42,28);
+COMMIT;
+SET @commit_id=43;
+INSERT INTO t8 VALUES (43,43);
+INSERT INTO t8 VALUES (44,44);
+UPDATE t7 SET b=45 WHERE a=3;
+INSERT INTO t8 VALUES (46,46);
+INSERT INTO t8 VALUES (47,47);
+UPDATE t7 SET b=48 WHERE a=3;
+INSERT INTO t8 VALUES (49,49);
+INSERT INTO t8 VALUES (50,50);
+SET @commit_id=44;
+INSERT INTO t8 VALUES (51,51);
+INSERT INTO t8 VALUES (52,52);
+UPDATE t7 SET b=53 WHERE a=3;
+INSERT INTO t8 VALUES (54,54);
+INSERT INTO t8 VALUES (55,55);
+UPDATE t7 SET b=56 WHERE a=3;
+INSERT INTO t8 VALUES (57,57);
+UPDATE t7 SET b=58 WHERE a=3;
+INSERT INTO t8 VALUES (58,58);
+INSERT INTO t8 VALUES (59,59);
+INSERT INTO t8 VALUES (60,60);
+INSERT INTO t8 VALUES (61,61);
+UPDATE t7 SET b=62 WHERE a=3;
+INSERT INTO t8 VALUES (63,63);
+INSERT INTO t8 VALUES (64,64);
+INSERT INTO t8 VALUES (65,65);
+INSERT INTO t8 VALUES (66,66);
+UPDATE t7 SET b=67 WHERE a=3;
+INSERT INTO t8 VALUES (68,68);
+UPDATE t7 SET b=69 WHERE a=3;
+UPDATE t7 SET b=70 WHERE a=3;
+UPDATE t7 SET b=71 WHERE a=3;
+INSERT INTO t8 VALUES (72,72);
+UPDATE t7 SET b=73 WHERE a=3;
+UPDATE t7 SET b=74 WHERE a=3;
+UPDATE t7 SET b=75 WHERE a=3;
+UPDATE t7 SET b=76 WHERE a=3;
+INSERT INTO t8 VALUES (77,77);
+UPDATE t7 SET b=78 WHERE a=3;
+INSERT INTO t8 VALUES (79,79);
+UPDATE t7 SET b=80 WHERE a=3;
+INSERT INTO t8 VALUES (81,81);
+UPDATE t7 SET b=82 WHERE a=3;
+INSERT INTO t8 VALUES (83,83);
+UPDATE t7 SET b=84 WHERE a=3;
+SET @commit_id=45;
+INSERT INTO t8 VALUES (85,85);
+UPDATE t7 SET b=86 WHERE a=3;
+INSERT INTO t8 VALUES (87,87);
+SET @commit_id=46;
+INSERT INTO t8 VALUES (88,88);
+INSERT INTO t8 VALUES (89,89);
+INSERT INTO t8 VALUES (90,90);
+SET SESSION debug_dbug=@old_dbug;
+INSERT INTO t8 VALUES (91,91);
+INSERT INTO t8 VALUES (92,92);
+INSERT INTO t8 VALUES (93,93);
+INSERT INTO t8 VALUES (94,94);
+INSERT INTO t8 VALUES (95,95);
+INSERT INTO t8 VALUES (96,96);
+INSERT INTO t8 VALUES (97,97);
+INSERT INTO t8 VALUES (98,98);
+INSERT INTO t8 VALUES (99,99);
+SELECT * FROM t7 ORDER BY a;
+a	b
+1	1
+2	2
+3	86
+4	4
+5	5
+SELECT * FROM t8 ORDER BY a;
+a	b
+1	1
+2	2
+3	3
+4	4
+5	5
+6	6
+7	7
+8	8
+12	12
+13	13
+16	16
+18	18
+19	19
+21	21
+23	24
+24	24
+26	26
+28	28
+29	28
+30	28
+31	28
+32	28
+33	28
+34	28
+35	28
+36	28
+37	28
+38	28
+39	28
+40	28
+41	28
+42	28
+43	43
+44	44
+46	46
+47	47
+49	49
+50	50
+51	51
+52	52
+54	54
+55	55
+57	57
+58	58
+59	59
+60	60
+61	61
+63	63
+64	64
+65	65
+66	66
+68	68
+72	72
+77	77
+79	79
+81	81
+83	83
+85	85
+87	87
+88	88
+89	89
+90	90
+91	91
+92	92
+93	93
+94	94
+95	95
+96	96
+97	97
+98	98
+99	99
+include/save_master_gtid.inc
+include/start_slave.inc
+include/sync_with_master_gtid.inc
+SELECT * FROM t7 ORDER BY a;
+a	b
+1	1
+2	2
+3	86
+4	4
+5	5
+SELECT * FROM t8 ORDER BY a;
+a	b
+1	1
+2	2
+3	3
+4	4
+5	5
+6	6
+7	7
+8	8
+12	12
+13	13
+16	16
+18	18
+19	19
+21	21
+23	24
+24	24
+26	26
+28	28
+29	28
+30	28
+31	28
+32	28
+33	28
+34	28
+35	28
+36	28
+37	28
+38	28
+39	28
+40	28
+41	28
+42	28
+43	43
+44	44
+46	46
+47	47
+49	49
+50	50
+51	51
+52	52
+54	54
+55	55
+57	57
+58	58
+59	59
+60	60
+61	61
+63	63
+64	64
+65	65
+66	66
+68	68
+72	72
+77	77
+79	79
+81	81
+83	83
+85	85
+87	87
+88	88
+89	89
+90	90
+91	91
+92	92
+93	93
+94	94
+95	95
+96	96
+97	97
+98	98
+99	99
+include/stop_slave.inc
+SET GLOBAL slave_transaction_retries= @old_retries;
+include/start_slave.inc
 include/stop_slave.inc
 SET GLOBAL slave_parallel_threads=@old_parallel_threads;
 include/start_slave.inc
 SET DEBUG_SYNC= 'RESET';
 DROP function foo;
-DROP TABLE t1,t2,t3,t4,t5,t6;
+DROP TABLE t1,t2,t3,t4,t5,t6,t7,t8;
 SET DEBUG_SYNC= 'RESET';
 include/rpl_end.inc

mysql-test/suite/rpl/t/rpl_parallel.test

@@ -1959,6 +1959,208 @@ SET GLOBAL slave_parallel_mode='conservative';
 --source include/start_slave.inc
 
 
+--echo *** MDEV-7847: "Slave worker thread retried transaction 10 time(s) in vain, giving up", followed by replication hanging ***
+--echo *** MDEV-7882: Excessive transaction retry in parallel replication ***
+
+--connection server_1
+CREATE TABLE t7 (a int PRIMARY KEY, b INT) ENGINE=InnoDB;
+CREATE TABLE t8 (a int PRIMARY KEY, b INT) ENGINE=InnoDB;
+--save_master_pos
+
+--connection server_2
+--sync_with_master
+--source include/stop_slave.inc
+SET GLOBAL slave_parallel_threads=40;
+SELECT @old_retries:=@@GLOBAL.slave_transaction_retries;
+SET GLOBAL slave_transaction_retries= 5;
+
+
+# Using dbug error injection, we artificially create event groups with a lot of
+# conflicting transactions in each event group. The bugs were originally seen
+# "in the wild" with transactions that did not conflict on the master, and only
+# conflicted very rarely on the slave (maybe some edge case with InnoDB btree
+# page splits or something like that). The event groups here loosely reflect
+# the structure of the original failure's group commits.
+
+
+--connection server_1
+INSERT INTO t7 VALUES (1,1), (2,2), (3,3), (4,4), (5,5);
+SET @old_dbug= @@SESSION.debug_dbug;
+SET @commit_id= 42;
+SET SESSION debug_dbug="+d,binlog_force_commit_id";
+INSERT INTO t8 VALUES (1,1);
+INSERT INTO t8 VALUES (2,2);
+INSERT INTO t8 VALUES (3,3);
+INSERT INTO t8 VALUES (4,4);
+INSERT INTO t8 VALUES (5,5);
+INSERT INTO t8 VALUES (6,6);
+INSERT INTO t8 VALUES (7,7);
+INSERT INTO t8 VALUES (8,8);
+
+UPDATE t7 SET b=9 WHERE a=3;
+UPDATE t7 SET b=10 WHERE a=3;
+UPDATE t7 SET b=11 WHERE a=3;
+
+INSERT INTO t8 VALUES (12,12);
+INSERT INTO t8 VALUES (13,13);
+
+UPDATE t7 SET b=14 WHERE a=3;
+UPDATE t7 SET b=15 WHERE a=3;
+
+INSERT INTO t8 VALUES (16,16);
+
+UPDATE t7 SET b=17 WHERE a=3;
+
+INSERT INTO t8 VALUES (18,18);
+INSERT INTO t8 VALUES (19,19);
+
+UPDATE t7 SET b=20 WHERE a=3;
+
+INSERT INTO t8 VALUES (21,21);
+
+UPDATE t7 SET b=22 WHERE a=3;
+
+INSERT INTO t8 VALUES (23,24);
+INSERT INTO t8 VALUES (24,24);
+
+UPDATE t7 SET b=25 WHERE a=3;
+
+INSERT INTO t8 VALUES (26,26);
+
+UPDATE t7 SET b=27 WHERE a=3;
+
+BEGIN;
+INSERT INTO t8 VALUES (28,28);
+INSERT INTO t8 VALUES (29,28), (30,28);
+INSERT INTO t8 VALUES (31,28);
+INSERT INTO t8 VALUES (32,28);
+INSERT INTO t8 VALUES (33,28);
+INSERT INTO t8 VALUES (34,28);
+INSERT INTO t8 VALUES (35,28);
+INSERT INTO t8 VALUES (36,28);
+INSERT INTO t8 VALUES (37,28);
+INSERT INTO t8 VALUES (38,28);
+INSERT INTO t8 VALUES (39,28);
+INSERT INTO t8 VALUES (40,28);
+INSERT INTO t8 VALUES (41,28);
+INSERT INTO t8 VALUES (42,28);
+COMMIT;
+
+
+SET @commit_id=43;
+INSERT INTO t8 VALUES (43,43);
+INSERT INTO t8 VALUES (44,44);
+
+UPDATE t7 SET b=45 WHERE a=3;
+
+INSERT INTO t8 VALUES (46,46);
+INSERT INTO t8 VALUES (47,47);
+
+UPDATE t7 SET b=48 WHERE a=3;
+
+INSERT INTO t8 VALUES (49,49);
+INSERT INTO t8 VALUES (50,50);
+
+
+SET @commit_id=44;
+INSERT INTO t8 VALUES (51,51);
+INSERT INTO t8 VALUES (52,52);
+
+UPDATE t7 SET b=53 WHERE a=3;
+
+INSERT INTO t8 VALUES (54,54);
+INSERT INTO t8 VALUES (55,55);
+
+UPDATE t7 SET b=56 WHERE a=3;
+
+INSERT INTO t8 VALUES (57,57);
+
+UPDATE t7 SET b=58 WHERE a=3;
+
+INSERT INTO t8 VALUES (58,58);
+INSERT INTO t8 VALUES (59,59);
+INSERT INTO t8 VALUES (60,60);
+INSERT INTO t8 VALUES (61,61);
+
+UPDATE t7 SET b=62 WHERE a=3;
+
+INSERT INTO t8 VALUES (63,63);
+INSERT INTO t8 VALUES (64,64);
+INSERT INTO t8 VALUES (65,65);
+INSERT INTO t8 VALUES (66,66);
+
+UPDATE t7 SET b=67 WHERE a=3;
+
+INSERT INTO t8 VALUES (68,68);
+
+UPDATE t7 SET b=69 WHERE a=3;
+UPDATE t7 SET b=70 WHERE a=3;
+UPDATE t7 SET b=71 WHERE a=3;
+
+INSERT INTO t8 VALUES (72,72);
+
+UPDATE t7 SET b=73 WHERE a=3;
+UPDATE t7 SET b=74 WHERE a=3;
+UPDATE t7 SET b=75 WHERE a=3;
+UPDATE t7 SET b=76 WHERE a=3;
+
+INSERT INTO t8 VALUES (77,77);
+
+UPDATE t7 SET b=78 WHERE a=3;
+
+INSERT INTO t8 VALUES (79,79);
+
+UPDATE t7 SET b=80 WHERE a=3;
+
+INSERT INTO t8 VALUES (81,81);
+
+UPDATE t7 SET b=82 WHERE a=3;
+
+INSERT INTO t8 VALUES (83,83);
+
+UPDATE t7 SET b=84 WHERE a=3;
+
+
+SET @commit_id=45;
+INSERT INTO t8 VALUES (85,85);
+UPDATE t7 SET b=86 WHERE a=3;
+INSERT INTO t8 VALUES (87,87);
+
+
+SET @commit_id=46;
+INSERT INTO t8 VALUES (88,88);
+INSERT INTO t8 VALUES (89,89);
+INSERT INTO t8 VALUES (90,90);
+
+SET SESSION debug_dbug=@old_dbug;
+
+INSERT INTO t8 VALUES (91,91);
+INSERT INTO t8 VALUES (92,92);
+INSERT INTO t8 VALUES (93,93);
+INSERT INTO t8 VALUES (94,94);
+INSERT INTO t8 VALUES (95,95);
+INSERT INTO t8 VALUES (96,96);
+INSERT INTO t8 VALUES (97,97);
+INSERT INTO t8 VALUES (98,98);
+INSERT INTO t8 VALUES (99,99);
+
+
+SELECT * FROM t7 ORDER BY a;
+SELECT * FROM t8 ORDER BY a;
+--source include/save_master_gtid.inc
+
+
+--connection server_2
+--source include/start_slave.inc
+--source include/sync_with_master_gtid.inc
+SELECT * FROM t7 ORDER BY a;
+SELECT * FROM t8 ORDER BY a;
+
+--source include/stop_slave.inc
+SET GLOBAL slave_transaction_retries= @old_retries;
+--source include/start_slave.inc
+
+
 # Clean up.
 --connection server_2
 --source include/stop_slave.inc
@@ -1968,7 +2170,7 @@ SET DEBUG_SYNC= 'RESET';
 
 --connection server_1
 DROP function foo;
-DROP TABLE t1,t2,t3,t4,t5,t6;
+DROP TABLE t1,t2,t3,t4,t5,t6,t7,t8;
 SET DEBUG_SYNC= 'RESET';
 
 --source include/rpl_end.inc

sql/log.cc

@@ -7360,6 +7360,15 @@ MYSQL_BIN_LOG::trx_group_commit_leader(group_commit_entry *leader)
   if (likely(is_open()))                       // Should always be true
   {
     commit_id= (last_in_queue == leader ? 0 : (uint64)leader->thd->query_id);
+    DBUG_EXECUTE_IF("binlog_force_commit_id",
+      {
+        const LEX_STRING name= { C_STRING_WITH_LEN("commit_id") };
+        bool null_value;
+        user_var_entry *entry=
+          (user_var_entry*) my_hash_search(&leader->thd->user_vars,
+                                           (uchar*) name.str, name.length);
+        commit_id= entry->val_int(&null_value);
+      });
     /*
       Commit every transaction in the queue.
 

sql/rpl_parallel.cc

@@ -112,6 +112,7 @@ finish_event_group(rpl_parallel_thread *rpt, uint64 sub_id,
   wait_for_commit *wfc= &rgi->commit_orderer;
   int err;
 
+  thd->get_stmt_da()->set_overwrite_status(true);
   /*
     Remove any left-over registration to wait for a prior commit to
     complete. Normally, such wait would already have been removed at
@@ -128,14 +129,14 @@ finish_event_group(rpl_parallel_thread *rpt, uint64 sub_id,
     for us to complete and rely on this also ensuring that any other
     event in the group has completed.
 
-    But in the error case, we have to abort anyway, and it seems best
+    And in the error case, correct GCO lifetime relies on the fact that once
-    to just complete as quickly as possible with unregister. Anyone
+    the last event group in the GCO has executed wait_for_prior_commit(),
-    waiting for us will in any case receive the error back from their
+    all earlier event groups have also committed; this way no more
-    wait_for_prior_commit() call.
+    mark_start_commit() calls can be made and it is safe to de-allocate
+    the GCO.
   */
-  if (rgi->worker_error)
+  err= wfc->wait_for_prior_commit(thd);
-    wfc->unregister_wait_for_prior_commit();
+  if (unlikely(err) && !rgi->worker_error)
-  else if ((err= wfc->wait_for_prior_commit(thd)))
     signal_error_to_sql_driver_thread(thd, rgi, err);
   thd->wait_for_commit_ptr= NULL;
 
@@ -192,6 +193,10 @@ finish_event_group(rpl_parallel_thread *rpt, uint64 sub_id,
 
   thd->clear_error();
   thd->reset_killed();
+  /*
+    Would do thd->get_stmt_da()->set_overwrite_status(false) here, but
+    reset_diagnostics_area() already does that.
+  */
   thd->get_stmt_da()->reset_diagnostics_area();
   wfc->wakeup_subsequent_commits(rgi->worker_error);
 }
@@ -385,16 +390,10 @@ do_retry:
     register_wait_for_prior_event_group_commit(rgi, entry);
     mysql_mutex_unlock(&entry->LOCK_parallel_entry);
 
-    if (rgi->speculation != rpl_group_info::SPECULATE_OPTIMISTIC)
-      break;
-
     /*
-      We speculatively tried to run this in parallel with prior event groups,
+      Let us wait for all prior transactions to complete before trying again.
-      but it did not work for some reason.
+      This way, we avoid repeatedly conflicting with and getting deadlock
-
+      killed by the same earlier transaction.
-      So let us wait for all prior transactions to complete before trying
-      again. This way, we avoid repeatedly retrying and failing a small
-      transaction that conflicts with a prior long-running one.
     */
     if (!(err= thd->wait_for_prior_commit()))
     {
@@ -800,8 +799,7 @@ handle_rpl_parallel_thread(void *arg)
 
         if (unlikely(entry->stop_on_error_sub_id <= rgi->wait_commit_sub_id))
           skip_event_group= true;
-        else
+        register_wait_for_prior_event_group_commit(rgi, entry);
-          register_wait_for_prior_event_group_commit(rgi, entry);
 
         unlock_or_exit_cond(thd, &entry->LOCK_parallel_entry,
                             &did_enter_cond, &old_stage);
@@ -888,7 +886,9 @@ handle_rpl_parallel_thread(void *arg)
       else
       {
         delete qev->ev;
+        thd->get_stmt_da()->set_overwrite_status(true);
         err= thd->wait_for_prior_commit();
+        thd->get_stmt_da()->set_overwrite_status(false);
       }
 
       end_of_group=

sql/rpl_parallel.h

@@ -53,7 +53,7 @@ struct group_commit_orderer {
   group_commit_orderer *prev_gco;
   group_commit_orderer *next_gco;
   /*
-    The sub_id of last event group in this the previous GCO.
+    The sub_id of last event group in the previous GCO.
     Only valid if prev_gco != NULL.
   */
   uint64 prior_sub_id;