A little follow up on the explains:
here is the query as run when displaying a ticket:
mysql> EXPLAIN SELECT DISTINCT main.* FROM Users main JOIN Principals
Principals_1 ON ( Principals_1.id = main.id ) JOIN CachedGroupMembers
CachedGroupMembers_2 ON ( CachedGroupMembers_2.MemberId = Principals_1.id )
JOIN Groups Groups_3 ON ( Groups_3.id = CachedGroupMembers_2.GroupId ) WHERE
(Principals_1.Disabled = '0') AND (Principals_1.id != '1') AND
(Principals_1.PrincipalType = 'User') AND ((Groups_3.Domain = 'RT::Queue-Role'
AND Groups_3.Instance = '3') OR (Groups_3.Domain = 'RT::System-Role')) AND
(Groups_3.Type = 'AdminCc') ORDER BY main.Name ASC;
+----+-------------+----------------------+--------+--------------------------------+------------+---------+-------------------------------------+------+----------------------------------------------+
| id | select_type | table | type | possible_keys
| key | key_len | ref | rows | Extra
|
+----+-------------+----------------------+--------+--------------------------------+------------+---------+-------------------------------------+------+----------------------------------------------+
| 1 | SIMPLE | main | range | PRIMARY
| PRIMARY | 4 | NULL | 316 | Using
where; Using temporary; Using filesort |
| 1 | SIMPLE | Groups_3 | ref | PRIMARY,Groups1,Groups2
| Groups2 | 67 | const | 4000 | Using
where; Distinct |
| 1 | SIMPLE | Principals_1 | eq_ref | PRIMARY
| PRIMARY | 4 | rt3.main.id | 1 | Using
where; Distinct |
| 1 | SIMPLE | CachedGroupMembers_2 | ref |
DisGrouMem,CachedGroupMembers3 | DisGrouMem | 10 |
rt3.Groups_3.id,rt3.Principals_1.id | 1 | Using where; Using index; Distinct
|
+----+-------------+----------------------+--------+--------------------------------+------------+---------+-------------------------------------+------+----------------------------------------------+
4 rows in set (0.00 sec)
here is the modified removing the OR
mysql> EXPLAIN SELECT DISTINCT main.* FROM Users main JOIN Principals
Principals_1 ON ( Principals_1.id = main.id ) JOIN CachedGroupMembers
CachedGroupMembers_2 ON ( CachedGroupMembers_2.MemberId = Principals_1.id )
JOIN Groups Groups_3 ON ( Groups_3.id = CachedGroupMembers_2.GroupId ) WHERE
(Principals_1.Disabled = '0') AND (Principals_1.id != '1') AND
(Principals_1.PrincipalType = 'User') AND ((Groups_3.Domain = 'RT::Queue-Role'
AND Groups_3.Instance = '3')) AND (Groups_3.Type = 'AdminCc') ORDER BY
main.Name ASC;
+----+-------------+----------------------+--------+--------------------------------+------------+---------+-----------------------------+------+-----------------------------------------------------------+
| id | select_type | table | type | possible_keys
| key | key_len | ref | rows | Extra
|
+----+-------------+----------------------+--------+--------------------------------+------------+---------+-----------------------------+------+-----------------------------------------------------------+
| 1 | SIMPLE | Groups_3 | ref | PRIMARY,Groups1,Groups2
| Groups1 | 139 | const,const,const | 1 | Using where;
Using index; Using temporary; Using filesort |
| 1 | SIMPLE | main | range | PRIMARY
| PRIMARY | 4 | NULL | 316 | Using where
|
| 1 | SIMPLE | Principals_1 | eq_ref | PRIMARY
| PRIMARY | 4 | rt3.main.id | 1 | Using where;
Distinct |
| 1 | SIMPLE | CachedGroupMembers_2 | ref |
DisGrouMem,CachedGroupMembers3 | DisGrouMem | 10 |
rt3.Groups_3.id,rt3.main.id | 1 | Using where; Using index; Distinct
|
+----+-------------+----------------------+--------+--------------------------------+------------+---------+-----------------------------+------+-----------------------------------------------------------+
4 rows in set (0.00 sec)
index listing from Principals:
mysql> show index from Principals;
+------------+------------+-------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name |
Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment |
+------------+------------+-------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| Principals | 0 | PRIMARY | 1 | id | A
| 22309 | NULL | NULL | | BTREE | NULL |
| Principals | 1 | Principals2 | 1 | ObjectId | A
| 22309 | NULL | NULL | YES | BTREE | NULL |
+------------+------------+-------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
2 rows in set (0.00 sec)
not sure if this helps tracking it down... still having figured out what the
Groups_3.Domain = 'RT::System-Role'...
Nicola
-----Original Message-----
From: [email protected] on behalf of Foggi, Nicola
Sent: Fri 6/25/2010 11:07 AM
To: Ruslan Zakirov
Cc: [email protected]
Subject: Re: [rt-users] slow mysql query after upgrade from 3.8.6 to 3.8.8
UseSQLForACLChecks is set as the default under RT_Config.pm to
"Set($UseSQLForACLChecks, undef);"
here is the explain:
EXPLAIN SELECT DISTINCT main.* FROM Users main JOIN Principals Principals_1 ON
( Principals_1.id = main.id ) JOIN CachedGroupMembers CachedGroupMembers_2 ON
( CachedGroupMembers_2.MemberId = Principals_1.id ) JOIN Groups Groups_3 ON (
Groups_3.id = CachedGroupMembers_2.GroupId ) WHERE (Principals_1.Disabled =
'0') AND (Principals_1.id != '1') AND (Principals_1.PrincipalType = 'User') AND
((Groups_3.Domain = 'RT::Queue-Role' AND Groups_3.Instance = '3') OR
(Groups_3.Domain = 'RT::System-Role')) AND (Groups_3.Type = 'AdminCc') ORDER
BY main.Name ASC;
+----+-------------+----------------------+--------+--------------------------------+------------+---------+-------------------------------------+------+----------------------------------------------+
| id | select_type | table | type | possible_keys
| key | key_len | ref | rows | Extra
|
+----+-------------+----------------------+--------+--------------------------------+------------+---------+-------------------------------------+------+----------------------------------------------+
| 1 | SIMPLE | main | range | PRIMARY
| PRIMARY | 4 | NULL | 316 | Using
where; Using temporary; Using filesort |
| 1 | SIMPLE | Groups_3 | ref | PRIMARY,Groups1,Groups2
| Groups2 | 67 | const | 3992 | Using
where; Distinct |
| 1 | SIMPLE | Principals_1 | eq_ref | PRIMARY
| PRIMARY | 4 | rt3.main.id | 1 | Using
where; Distinct |
| 1 | SIMPLE | CachedGroupMembers_2 | ref |
DisGrouMem,CachedGroupMembers3 | DisGrouMem | 10 |
rt3.Groups_3.id,rt3.Principals_1.id | 1 | Using where; Using index; Distinct
|
+----+-------------+----------------------+--------+--------------------------------+------------+---------+-------------------------------------+------+----------------------------------------------+
4 rows in set (0.00 sec)
here is the indexes:
mysql> show index from Groups;
+--------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation |
Cardinality | Sub_part | Packed | Null | Index_type | Comment |
+--------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| Groups | 0 | PRIMARY | 1 | id | A |
21563 | NULL | NULL | | BTREE | NULL |
| Groups | 1 | Groups1 | 1 | Domain | A |
31 | NULL | NULL | YES | BTREE | NULL |
| Groups | 1 | Groups1 | 2 | Instance | A |
21563 | NULL | NULL | YES | BTREE | NULL |
| Groups | 1 | Groups1 | 3 | Type | A |
21563 | NULL | NULL | YES | BTREE | NULL |
| Groups | 1 | Groups1 | 4 | id | A |
21563 | NULL | NULL | | BTREE | NULL |
| Groups | 1 | Groups2 | 1 | Type | A |
10 | NULL | NULL | YES | BTREE | NULL |
| Groups | 1 | Groups2 | 2 | Instance | A |
21563 | NULL | NULL | YES | BTREE | NULL |
+--------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
7 rows in set (0.00 sec)
I did find in some trial and error testing if I drop the " OR (Groups_3.Domain
= 'RT::System-Role')" from the query it gives the same results in under 1
second vs 11-12 seconds, but bot sure what that OR is adding into the mix.
That query is what is performed when I display a ticket through the web
interface.
Any help is appreciated!
Nicola
-----Original Message-----
From: [email protected] on behalf of Ruslan Zakirov
Sent: Fri 6/25/2010 11:05 AM
To: Foggi, Nicola
Cc: [email protected]
Subject: Re: [rt-users] slow mysql query after upgrade from 3.8.6 to 3.8.8
Hello,
Do you use SQLForACLChecks option?
Where is EXPLAIN for this query?
Show indexes from Groups table.
On Fri, Jun 25, 2010 at 8:04 AM, Foggi, Nicola <[email protected]> wrote:
>
> hey everyone,
>
> after upgrading from 3.8.6 to 3.8.8 we're getting a slow query on this
> query:
>
> use rt3;
> SELECT DISTINCT main.* FROM Users main JOIN Principals Principals_1 ON (
> Principals_1.id = main.id ) JOIN CachedGroupMembers CachedGroupMembers_2 ON
> ( CachedGroupMembers_2.MemberId = Principals_1.id ) JOIN Groups Groups_3 ON
> ( Groups_3.id = CachedGroupMembers_2.GroupId ) WHERE (Principals_1.Disabled
> = '0') AND (Principals_1.id != '1') AND (Principals_1.PrincipalType =
> 'User') AND ((Groups_3.Domain = 'RT::Queue-Role' AND Groups_3.Instance =
> '3') OR (Groups_3.Domain = 'RT::System-Role')) AND (Groups_3.Type =
> 'AdminCc') ORDER BY main.Name ASC;
> # Time: 100624 22:44:20
> # u...@host: rt_user[rt_user] @ rt.internal [10.12.10.72]
> # Query_time: 13 Lock_time: 0 Rows_sent: 1 Rows_examined: 0
> SELECT GET_LOCK('Apache-Session-dc95ab57bb8d19e23fa6fa70314e3c0e', 3600);
> # Time: 100624 22:49:28
>
> when loading any ticket page. I've verified the cachedgroupmembers3 index
> is in place:
>
> show index from CachedGroupMembers;
> ...
> | CachedGroupMembers | 1 | CachedGroupMembers3 | 1 |
> MemberId | A | 36038 | NULL | NULL | YES |
> BTREE | NULL |
> | CachedGroupMembers | 1 | CachedGroupMembers3 | 2 |
> ImmediateParentId | A | 36038 | NULL | NULL | YES |
> BTREE | NULL |
>
>
> but still extremely slow... any ideas? it's pretty bad...
>
> Nicola
>
> Discover RT's hidden secrets with RT Essentials from O'Reilly Media.
> Buy a copy at http://rtbook.bestpractical.com
>
--
Best regards, Ruslan.
Discover RT's hidden secrets with RT Essentials from O'Reilly Media.
Buy a copy at http://rtbook.bestpractical.com
