slow query in Inndb (4 replies)

I hope this section will be ok for this.
I have database using InnoDB engine. Unfortunately one query needs over 7 seconds to compleat. I can't find what makes is so slow. Time is not connected with hdd however CPU is working at 100% to make this query. I saw the same database with more data working in one-two seconds. Probably because of change in structure which I can't find. I checked also for triggers tried optymize and such.

SELECT c.id AS id, lastname AS customername, status, address, zip,
city, countryid, countries.name AS country, email, ten, ssn, c.info AS
info, message, c.divisionid, c.paytime AS paytime, COALESCE(b.value, 0) AS
balance, COALESCE(t.value, 0) AS tariffvalue, s.account, s.warncount,
s.online, (CASE WHEN s.account = s.acsum THEN 1 WHEN s.acsum > 0 THEN 2
ELSE 0 END) AS nodeac, (CASE WHEN s.warncount = s.warnsum THEN 1 WHEN
s.warnsum > 0 THEN 2 ELSE 0 END) AS nodewarn FROM customersview c LEFT
JOIN countries ON (c.countryid = countries.id) LEFT JOIN (SELECT
SUM(value) AS value, customerid FROM cash GROUP BY customerid) b ON
(b.customerid = c.id) LEFT JOIN (SELECT customerid, SUM((1)) AS value FROM
assignments LEFT JOIN tariffs t ON (t.id = tariffid) LEFT JOIN liabilities
l ON (l.id = liabilityid AND period != 0) WHERE (datefrom <= 1337932817 OR
datefrom = 0) AND (dateto > 1337932817 OR dateto = 0) GROUP BY customerid)
t ON (t.customerid = c.id) LEFT JOIN (SELECT ownerid, SUM(access) AS
acsum, COUNT(access) AS account, SUM(warning) AS warnsum, COUNT(warning)
AS warncount, (CASE WHEN MAX(lastonline) > 1337932817 - 0 THEN 1 ELSE 0
END) AS online FROM nodes WHERE ownerid > 0 GROUP BY ownerid ) s ON
(s.ownerid = c.id);

EXPLAIN shows:

Lp.	id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	1	PRIMARY	c	ALL					939	Using where
2	1	PRIMARY	countries	eq_ref	PRIMARY	PRIMARY	4	lms.c.countryid	1	
3	1	PRIMARY	<derived2>	ALL					1281	
4	1	PRIMARY	<derived3>	ALL					642	
5	1	PRIMARY	<derived4>	ALL					644	
6	6	DEPENDENT SUBQUERY	e	index		userid	8		276	Using where; Using index
7	6	DEPENDENT SUBQUERY	a	eq_ref	customerassignment	customerassignment	8	lms.e.customergroupid,lms.c.id	1	Using where; Using index
8	4	DERIVED	nodes	index	ownerid	ownerid	4		1688	Using where
9	3	DERIVED	assignments	ALL					772	Using where; Using temporary; Using filesort
10	3	DERIVED	t	eq_ref	PRIMARY	PRIMARY	4	lms.assignments.tariffid	1	Using index
11	3	DERIVED	l	eq_ref	PRIMARY	PRIMARY	4	lms.assignments.liabilityid	1	Using index
12	2	DERIVED	cash	index		customerid	4		53671