BUG#39851: race between check_testcase and tests running 'show processlist'

Problem 1: not_embedded_server runs SELECT FROM I_S.PROCESSLIST near the beginning.
check_testcase executes a query to the server before that. There is a race here,
because there is no guarantee that the thread executing check_testcase's query is
finished.
Problem 2: The SELECT FROM I_S.PROCESSLIST doens't seem very useful in the test.
It's at least misplaced.
Fix to both problems: Comment out SELECT FROM I_S.PROCESSLIST.

2 files changed, 23 insertions, 16 deletions

diff --git a/mysql-test/r/not_embedded_server.result b/mysql-test/r/not_embedded_server.result
index 89f48a1ea56..4373d6356d9 100644
--- a/mysql-test/r/not_embedded_server.result
+++ b/mysql-test/r/not_embedded_server.result
@@ -1,7 +1,2 @@
-prepare stmt1 from ' SELECT * FROM INFORMATION_SCHEMA.PROCESSLIST WHERE COMMAND!=\'Daemon\' ';
-execute stmt1;
-ID	USER	HOST	DB	COMMAND	TIME	STATE	INFO
-number	root	localhost	test	Query	time	executing	SELECT * FROM INFORMATION_SCHEMA.PROCESSLIST WHERE COMMAND!='Daemon'
-deallocate prepare stmt1;
 FLUSH STATUS;
 Value of com_select did not change
diff --git a/mysql-test/t/not_embedded_server.test b/mysql-test/t/not_embedded_server.test
index fe6b8825a87..562194a62a4 100644
--- a/mysql-test/t/not_embedded_server.test
+++ b/mysql-test/t/not_embedded_server.test
@@ -4,21 +4,33 @@
 
 -- source include/not_embedded.inc
 
+
+# The following fails sporadically because 'check-testcase' runs
+# queries before this test and there is no way to guarantee that any
+# previous process finishes.  The purpose of the test is not clearly
+# stated, there is no reference to any bug report, and "select from
+# I_S from prepared statement" doesn't look like something that's
+# really imporant to test.  I'm commenting out this for now.  If
+# anyone wants to keep this, please fix the race and motivate why we
+# need to test this.  If you see this comment and it is after mid-2009
+# or so, feel free to remove this test from the file.  /Sven
 #
-# Show full process list with prepare
-# To not show other connections, this must be the first test and we must
-# have a server restart before this one
 #
-# We don't have any 4.1 tests as we use I_S to query the PROCESSLIST to
-# exclude system threads that may/may not be active in the server
-# (namely the ndb injector thread)
+## Show full process list with prepare
+## To not show other connections, this must be the first test and we must
+## have a server restart before this one
+##
+## We don't have any 4.1 tests as we use I_S to query the PROCESSLIST to
+## exclude system threads that may/may not be active in the server
+## (namely the ndb injector thread)
+##
+## End of 4.1 tests
 #
-# End of 4.1 tests
+#prepare stmt1 from ' SELECT * FROM INFORMATION_SCHEMA.PROCESSLIST WHERE COMMAND!=\'Daemon\' ';
+#--replace_column 1 number 6 time 3 localhost
+#execute stmt1;
+#deallocate prepare stmt1;
 
-prepare stmt1 from ' SELECT * FROM INFORMATION_SCHEMA.PROCESSLIST WHERE COMMAND!=\'Daemon\' ';
---replace_column 1 number 6 time 3 localhost
-execute stmt1;
-deallocate prepare stmt1;
 
 
 #