[TYPO3] indexed_search can congest MySQL server for long time

[Christian Lerrahn]

Hi,
I'm having trouble with indexed_search. I'm using it on a site which
has lots of text. The database is only about 350MB (a dump would be
about 500MB) big but it takes ages to search for anything. If I search
for one word that is rather prominent on the site, the search takes
about 1 min! I have recreated my index which seems to help a bit but not
much.

However, my big problem is that with several simultaneous searches, you
can congest the MySQL server for long time (apparently up to 30 min or
so). During that time my server load can go up to 50 because MySQL is
sucking 95% of the CPU. It is not exactly a slow box and I've never had
problems with any other services. However, sometimes I've had to kill
MySQL to get the box to run properly again. Has anyone had this problem
before? The search on typo3.org seems to be a lot faster. Is it
possible to tweak MySQL so that it does not run into this? At the
moment this problem might even expose me to DoS attacks!

Cheers,
Christian