I just came across this thread, searching for the same issue in MP 1.60 (and earlier). In my case, I have Avast AV running, and excluding the list of directories in this thread, plus the MySQL path has brought the delay of pressing "record" in the record dialog box down to about 8 seconds, which is much more acceptable. I'm wondering if there is anything else I can do to help optimize this? I ran the "mysqlcheck --user=root --pass=MediaPortal --auto-repair MPTVDB" and found no issues. Are there any indexes on the tables being used by stored procedures?
I have approximately 260 TV channels, and about 90 radio channels along with 14 days of guide data, so I'm sure my configuration is probably a bit larger than most people's.
I should also add that I am still using MySQL 5.1.