Permalink error

Hello everyone,

I have a bug for several weeks now with WordPress, the following lines appears at the top of the pages :

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32977 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32977 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32972 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32972 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32974 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32974 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32969 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32969 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32975 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32975 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32970 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32970 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32982 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32982 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32977 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32977 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32999 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32999 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32994 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32994 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32988 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32988 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32983 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32983 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32984 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32984 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32979 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32979 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32983 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32983 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32978 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32978 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32985 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32985 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32980 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32980 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32986 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32986 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32981 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32981 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 33002 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 33002 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32997 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32997 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32985 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32985 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32980 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 204

Warning: preg_match(): Compilation failed: regular expression is too large at offset 32980 in /homepages/9/d432832441/htdocs/mywebsite/wp-includes/class-wp.php on line 205

I tried this :

– Update to WP4
– Update child theme
– Update all plugins
– Desactivate all plugins
– Desactivate child theme

The problem is still there.

In fact the only way to get rid of it is to change permalinks for default https://www.mywebsite.com/?p=123

But as soon as I reactivate https://www.mywebsite.com/%category%/ the problem is here again.

My website is on a dedicated server, running for 1 year now without any problem under WP 3.6.1 (now WP4)

But on August 23th I decided to update more thant 300 jobs and to change permalinks for resumes (there are 4700 resumes) and the problem appears !

I also have two problems which are I think related :

– the server CPU usage sometimes goes up from 5% to 50% in one minute, when I publish a new post

– the server crashes about one time every week since late August.

Any idea?

thank you

John