CACHE_ACCEL requested but no suitable object cache is present. You may want to install APC.

Backtrace:

#0 [internal function]: ObjectCache::newAccelerator(Array)
#1 /var/www/html/wiki/includes/objectcache/ObjectCache.php(62): call_user_func('ObjectCache::ne...', Array)
#2 /var/www/html/wiki/includes/objectcache/ObjectCache.php(50): ObjectCache::newFromParams(Array)
#3 /var/www/html/wiki/includes/objectcache/ObjectCache.php(23): ObjectCache::newFromId(3)
#4 /var/www/html/wiki/includes/GlobalFunctions.php(3600): ObjectCache::getInstance(3)
#5 /var/www/html/wiki/includes/Setup.php(402): wfGetMainCache()
#6 /var/www/html/wiki/includes/WebStart.php(157): require_once('/var/www/html/w...')
#7 /var/www/html/wiki/index.php(53): require('/var/www/html/w...')
#8 {main}