Xcache is no longer active so please see OPcache
XCache
New in Tiki6: Xcache stats are shown in Performance admin panel.
Make sure you allocate enough memory to XCache or you could have weirdness such as blank pages. Try a configuration with 128M cache and increase as needed. Please note that this value is for the whole server, thus, if you have many Tiki instances or other PHP apps, you should expect to increase accordingly.
Related: