Server response time high when InnoDB tables active but not being accessed I am experiencing high server response time (up to 5 seconds) when loading every Webpage on my server, ONLY when MySQL InnoDB tables are running.

The 5 second delay occurs even on static HTML pages with no call to any MySQL data table (and no other users on the site accessing other InnoDB linked webpages). 

As soon as the InnoDB is shutdown (MyISAM tables remain active), all pages (those that call DB or not) load very fast (including MyISAM tables) in about a second. 

How could InnoDB be causing server wide slow response, even when not being accessed?
[SOLVED]

I enabled query_cache_type=1 and query_cache_size=256M. 

The problem went away and the server response reduced from 6 seconds to 1 second. Very strange considering most recommend that Query cache should be disabled!