RT Slow to display

After upgrade from 3.6.5 to 3.8.1

RT Slow to display after I click on top-left link [Tickets]
I’ve also tried to do a fresh installation and loaded new schema.
I then loaded my data which I created by:
‘mysqldump -p rt3 --no-create-info --copmlete-insert > rt3.sql’

Mysql shows slow query:

Time: 081005 23:01:40

User@Host: rt_user[rt_user] @ localhost []

Query_time: 7 Lock_time: 0 Rows_sent: 2288 Rows_examined: 197572

SELECT DISTINCT main.* FROM Users main CROSS JOIN ACL ACL_2 JOIN
Principals Principals_1 ON ( Principals_1.id = main.id ) JOIN
CachedGroupMembers CachedGroupMembers_3 ON (
CachedGroupMembers_3.MemberId = Principals_1.id ) WHERE
(Principals_1.Disabled = ‘0’) AND (ACL_2.PrincipalId =
CachedGroupMembers_3.GroupId) AND (Principals_1.id != ‘1’) AND
(ACL_2.PrincipalType = ‘Group’) AND (Principals_1.PrincipalType =
‘User’) AND (ACL_2.RightName = ‘OwnTicket’ OR ACL_2.RightName =
‘SuperUser’) AND ((ACL_2.ObjectType = ‘RT::Queue’) OR
(ACL_2.ObjectType = ‘RT::System’)) ORDER BY main.Name ASC;

Pls Help,
Fezile