Cisco Unified MeetingPlace Release 8.0 -- Troubleshooting Application Server Installation
Voice User Interface is Significantly Slow
Problem: The Voice User Interface (VUI) is running significantly slow.
Solution: Check the settings of the write cache on your RAID controller (Default Write option). When the Default Write option is set to Write Back with BBU and the battery backup unit (BBU) fails or goes offline to a re-learn cycle, the Default Write setting fails back to Write Through. Without a working battery backup unit, this value is safer in case of power failure. But it also results in a performance penalty on the I/O subsystem of the host device. While the faulty battery backup unit is being repaired, the workaround is to enable the cache explicitly (Disk Cache option), even if it's set to the No Change setting, and put the Default Write setting explicitly to Write Through mode. This should return the voice user interface to an acceptable level until the faulty battery is replaced and you can safely set the Default Write option back to Write Back with BBU mode.