MDEV-20220: Merge 5.7 P_S replication table 'replication_applier_status_by_worker

Step2:
=====
Add two extra columns mentioned below.
---------------------------------------------------------------------------
|Column Name:           |        Description:                             |
|-------------------------------------------------------------------------|
|                       |                                                 |
|WORKER_IDLE_TIME       | Total idle time in seconds that the worker      |
|                       | thread has spent waiting for work from          |
|                       | co-ordinator thread                             |
|                       |                                                 |
|LAST_TRANS_RETRY_COUNT | Total number of retries attempted by last       |
|                       | transaction                                     |
---------------------------------------------------------------------------

2 files changed, 29 insertions, 1 deletions

diff --git a/sql/rpl_parallel.cc b/sql/rpl_parallel.cc
index d1ca1c1bf6f..44fba4e30e7 100644
--- a/sql/rpl_parallel.cc
+++ b/sql/rpl_parallel.cc
@@ -799,6 +799,7 @@ do_retry:
 
   mysql_mutex_lock(&rli->data_lock);
   ++rli->retried_trans;
+  ++rpt->last_trans_retry_count;
   statistic_increment(slave_retried_transactions, LOCK_status);
   mysql_mutex_unlock(&rli->data_lock);
 
@@ -1125,6 +1126,7 @@ handle_rpl_parallel_thread(void *arg)
     uint wait_count= 0;
     rpl_parallel_thread::queued_event *qev, *next_qev;
 
+    rpt->start_time_tracker();
     thd->ENTER_COND(&rpt->COND_rpl_thread, &rpt->LOCK_rpl_thread,
                     &stage_waiting_for_work_from_sql_thread, &old_stage);
     /*
@@ -1148,6 +1150,7 @@ handle_rpl_parallel_thread(void *arg)
     }
     rpt->dequeue1(events);
     thd->EXIT_COND(&old_stage);
+    rpt->add_to_worker_idle_time_and_reset();
 
   more_events:
     for (qev= events; qev; qev= next_qev)
@@ -1193,6 +1196,7 @@ handle_rpl_parallel_thread(void *arg)
       /* Handle a new event group, which will be initiated by a GTID event. */
       if ((event_type= qev->ev->get_type_code()) == GTID_EVENT)
       {
+        rpt->last_trans_retry_count= 0;
         rpt->last_seen_gtid= rgi->current_gtid;
         rpt->channel_name_length= (uint)rgi->rli->mi->connection_name.length;
         if (rpt->channel_name_length)
@@ -2015,7 +2019,8 @@ rpl_parallel_thread::loc_free_gco(group_commit_orderer *gco)
 
 
 rpl_parallel_thread::rpl_parallel_thread()
-  : channel_name_length(0), last_error_number(0), last_error_timestamp(0)
+  : channel_name_length(0), last_error_number(0), last_error_timestamp(0),
+    worker_idle_time(0), last_trans_retry_count(0), start_time(0)
 {
 }
 
diff --git a/sql/rpl_parallel.h b/sql/rpl_parallel.h
index 49e245176ff..4f7bd49120a 100644
--- a/sql/rpl_parallel.h
+++ b/sql/rpl_parallel.h
@@ -167,6 +167,29 @@ struct rpl_parallel_thread {
   int last_error_number;
   char last_error_message[MAX_SLAVE_ERRMSG];
   ulonglong last_error_timestamp;
+  ulonglong worker_idle_time;
+  ulong last_trans_retry_count;
+  ulonglong start_time;
+  void start_time_tracker()
+  {
+    start_time= microsecond_interval_timer();
+  }
+  ulonglong compute_time_lapsed()
+  {
+    return (ulonglong)((microsecond_interval_timer() - start_time) / 1000000.0);
+  }
+  void add_to_worker_idle_time_and_reset()
+  {
+    worker_idle_time+= compute_time_lapsed();
+    start_time=0;
+  }
+  ulonglong get_worker_idle_time()
+  {
+    if (start_time)
+      return compute_time_lapsed();
+    else
+      return worker_idle_time;
+  }
   void enqueue(queued_event *qev)
   {
     if (last_in_queue)