Drupal performance issue - too much time to establish a connection! My drupal site was working fine. Then i disabled access to public with some session thing, After a week or something , it is taking more than 12 second to establish a connection, then the loading is real quick. 

79 requests  ❘  35.47KB transferred  ❘  14.87s (onload: 14.87s, DOMContentLoaded: 13.06s)
home 
12.24s

css_6b268b79fc331b4fe1492e8a55b94a94.css
/sites/default/files/css
206ms

cometchatcss.php
394ms

........


another thing is its better for garland theme, so possibly theme problem , what what may cause this much waiting? not db_query as i checked even with blank page.tpl its taking 8+ sec! 
Please help!
Finally found problem - panel templates in my theme

for those who experience same , can follow these steps 


my site is optimized with APC and mod_deflate, so in pagespeed for chrome test, its 93/100
real problem was waiting time . chrome network analysis shows first GET took approx 18+ sec , then loading of other elements is real quick
after several test, i found my theme is causing delay. so i put a blank page.tpl in my theme. And you know it took 12+ sec to load that blank page! so it was not any db query problem!
so problem must be with .info, disabled css, then js, still no improvement
finally removed panel template declaration from .info , and now site took .3 sec to load!
next i tried with only one panel template in my theme, site took 1-2 sec


I have 10 panel templates in my theme.so panel templates affects site performance!