When I run dokuwiki, I notice that when each page loads it hangs about halfway through processing, then, in most cases, eventually loads the page.
I checked my php error log and found the following timeout notice;
[23-May-2006 10:15:09] PHP Fatal error: Maximum execution time of 60 seconds exceeded in /home/httpd/vhosts/wiki.havercamp.hopto.org/htdocs/lib/exe/js.php on line 281
I wrote a very simple test harness around js_compress and found that removing the single-quote and double-quote loops fixed the problem and I no longer had timeout issues.
I am running this on a development server with the following specs; celeron 450 with 128MB of RAM, and while the specs are low, everything, including dokuwiki without js_compress compressing double/single quotes, runs fine.