Why do I have so many extension tables in my slow query log?

Question

I want to optimize my mysql database and thus enabled the mysql slow query switch in my.cnf. What I see is many sys_log queries with many tables from my extension or others, too. Is this a slow query? How can I surpess it?

# Query_time: 0  Lock_time: 0  Rows_sent: 538  Rows_examined: 23611
SELECT sys_log.event_pid, sys_log.recuid, sys_log.tablename, sys_log.userid,    
sys_log.tstamp, be_users.realName, be_users.email FROM sys_log, be_users WHERE  
sys_log.tablename IN  
('tx_templavoila_datastructure','tx_templavoila_tmplobj','tx_chsystemrecherche_mo','tx_chsystemrecherche_s2','tx_chsystemrecherche_s3','tx_chsystemrecherche_s1','tx_chsystemreche che_da','tx_chsystemrecherche_de','tx_chsystemrecherche_wa','tx_chsystemrecherche_tb','tx_chsffoeag_fund','tx_charbeitsbeispiele_maxmedia','tx_chsammelstellen_plz','tx_chtreeview_example','tx_chspeditionsliste_route','tx_chspeditionsliste_k','tx_chhaendlersuche_plz','tx_veguestbook_entries','tx_lastupdate_custom','tt_content') AND sys_log.details_nr != 0 AND sys_log.userid = be_users.uid ORDER BY tstamp DESC LIMIT 0,1000;

Answer 1

It was suggested ages ago to crop your sys_log table from time to time (ie. leaving last 30 days) to keep preview of the recent users' activity.

edit: there's well known presentation by Jochen Weiland about oil changing - typical must-read position

Answer 2

you can always refresh reference indexes so it will be faster if you can`t clear sys_log btw if you wanna log long queries set time param for 2 sec or something like this