mcsgetsqlcount shows wrong number of running sql statements

CREATE DATABASE cal_test_db;
USE cal_test_db;
create table t1(a int, b int comment 'autoincrement=1') engine=columnstore;
select mcsflushcache();
select mcssettrace(0);
select mcssetparms("pmmaxmemorysmallside","2048000000");
select mcsgettrace();
select mcsgetversion()=calgetversion();
select mcsviewtablelock("t1");
select mcscleartablelock(0);
select mcslastinsertid("t1");
<show processlist; – for debug purposes>
select mcsgetsqlcount();
<show processlist; – for debug purposes>

should give: Running SQL statements 0, Waiting SQL statments 0
but sometime give: Running SQL statements 1, Waiting SQL statments 0

same time show processlist before and after doesn't show any process running:

Id User Host db Command Time State Info Progress
444 root localhost cal_test_db Query 0 starting show processlist 0.000
select mcsgetsqlcount();
mcsgetsqlcount()
Running SQL statements 1, Waiting SQL statments 0
show processlist;
Id User Host db Command Time State Info Progress
444 root localhost cal_test_db Query 0 starting show processlist 0.000