WP Super Cache: MySQL server has gone away on line: 124

I used WP Super Cache for long time no problems. I have a blog with more than 5000 posts. Suddenly I get all day when i try to post, save, edit

WordPress database error: [MySQL server has gone away]
SELECT option_value FROM x_options WHERE option_name = ” LIMIT 1

WordPress database error: [MySQL server has gone away]
SELECT form_id FROM x_tdomf_table_forms ORDER BY form_id ASC

WordPress database error: [MySQL server has gone away]
SELECT t.*, tt.* FROM x_terms AS t INNER JOIN x_term_taxonomy AS tt ON t.term_id = tt.term_id WHERE tt.taxonomy IN (‘category’) ORDER BY t.name ASC
MySQL server has gone away on line: 124

i talked to my host. they could not help me. they found some queries they killed them but soon after the error appeared.

i cleaned post revisions, no errors but soon after the error appeared.

today, 99% of what i did in admin was this error. page in admin was loading very slow.

i had the idea to clean cache and disabled the wp super cache. i do not have errors anymore.

there must be a conflict. these days will try to find the plugin that do not like the wp super cache. the ideea is that i have the same plugins as alway. i installed a few but unninstalled them.

from what i saw last days there was updates to some plugins i have like: GD Star Rating

anyone know something about this ? thank you.