After I upgraded from ATA 3.6.4 to the new version 3.7.1 my search doesn't work anymore:

Fatal error: Maximum execution time of 90 seconds exceeded in /var/www/domain.com/wp-content/themes/atahualpa/functions.php on line 296

what is the url?
who is the host?
do other functions work?
How big is the database (how many posts)
when was the last time you optimized the db?

It seems to have to do with the plugin Relevanssi. When I deactivate it, the search runs fine again. When I activate it, after a long time of waiting the error message above occured. Before the upgrade I didn't had such problems. Both, Atahualpa and Relevanssi worked fine together. So what to do now? Was there any change in the new ATA version that might cause this error?

have you built the index. I wonder if changing themes (an update is seen by wordpress as changing the theme) cause an index issue with the plugin.

Of course I have build the index. I also uninstalled and deleted the plugin and installed it anew, but nothing changes...

I just tested it on my site and it works fine.
can you answer my questions from post #2

sorry, no url, i host it by myself. other functions work properly so far. 200 posts, 150 custom posts, 50 pages and some other stuff. The database has a size of about 40 MB and is optimized every day.

Btw. I tried out Twenty Eleven Theme with Relevanssi activated and it runs fine. So I suppose the error must have to do with ATA?!

well I tried it with Atahualpa 3.7.1 and it worked fine for me, You might want to contact the plugin author and see if they have any ideas.

I don't think that this is a Releanssi issue. I downgraded back to ATA 3.6.4 and now Relevanssi and Atahualpa run together again very fine, without any problems.

does it always time out and show the same line number in functions.php?
do all searches time out?

yes, exactly that is the behaviour.

so if you search for something that doesn't exist, it still fails. That is very odd, the line the failure shows up on has nothing to do with the searching, it is doing a preg_split on the text it is passed to create an excerpt.

Since this is a local host have you checked for other errors? out of memory etc.

I have the caching activated in Relevanssi. Maybe that is the reason?

could be, try shutting it off