Add some variables to the generic threadpool, that could help to analyze

stalls etc better.

- thread_pool_exact_stats -  uses high precision timestamp for
the time when connection was added to the queue. This timestamp helps
calculating queuing time shown in I_S.THREADPOOL_QUEUES entries.

- If thread_pool_dedicated_listener is on, then each group will have its
own dedicated listener, that does not convert to worker.
With this variable on, the queueing time in I_S.THREADPOOL_QUEUES , and
actual queue size in I_S.THREADPOOOL_GROUPS will be more exact, since
IO request are immediately dequeued from poll, without delay.


Part of MDEV-19313.

1 files changed, 2 insertions, 0 deletions

diff --git a/sql/threadpool_common.cc b/sql/threadpool_common.cc
index 0cbd076016d..13e3886fb97 100644
--- a/sql/threadpool_common.cc
+++ b/sql/threadpool_common.cc
@@ -36,6 +36,8 @@ uint threadpool_max_threads;
 uint threadpool_oversubscribe;
 uint threadpool_mode;
 uint threadpool_prio_kickup_timer;
+my_bool threadpool_exact_stats;
+my_bool threadpool_dedicated_listener;
 
 /* Stats */
 TP_STATISTICS tp_stats;