[mod_python] psp problem

I use mod_python publish as handler,psp as template and MySQLdb to  
connect  the mysql .apache is 2.0.58 use perfork MPM

codes below:

from MySQLdb import connect
from mod_python import psp

def index (req):
    
conn=connect(**{'host':'localhost','user':'root','passwd':'','db':'test'})
    req.content_type = "text/html; charset=utf-8"
    psp.PSP(req,'templates/test.html').run({'name':'jack'})
    conn.close()

when I flush the exlpore, I see the 'show processlist' in the mysql 
shell is ceaselessly increasing ,why?