/mcpsuch as call processing. Then, you can increase the configuration settings for maximum number of calls for the media devices. When you activate Cisco IP Voice Media Streaming application as co-resident with Cisco Unified Communications Manager service, it can impact call processing performance. To increase the capacity settings for Music On Hold or annunciator from the default settings, it is suggested to activate Cisco IP Voice Media Streaming application on a server without activating Cisco Unified Communications Manager. The CPU performance is impacted by MOH when active callers are on hold or when multicast MOH audio streams are configured. Table 57: General Performance Results CPU Performance Configuration Notes 25–45% (7500 user OVA configuration) Dedicated MOH server, 1000 held calls, 500 MOH sources with greeting and periodic announcements. 25–45% (7500 user OVA configuration) Native call queuing with dedicated MOH server and annunciator server, 1000 queued calls, 500 MOH sources with greeting and periodic announcements. An annunciator can play up to 300 simultaneous greeting announcements. 15–35% (7500 user OVA configuration) Dedicated MOH server, 500 held calls, 500 MOH sources with greeting and periodic announcements. Table 58: Extrapolated Recommendations Recommendation Limit Configuration MOH: 500 held callers, 100 MOH sources, and 48 to 64 annunciator callers. When Cisco IP Voice Media Streaming application is co-resident with Cisco Unified Communications Manager on 2500 OVA (moderate call processing). MOH: 750 held callers, 250 MOH sources, and 250 annunciator callers. When Cisco IP Voice Media Streaming application is a dedicated server on 2500 OVA. MOH: 500 held callers, 250 MOH sources, and 128 annunciator callers. When Cisco IP Voice Media Streaming application is co-resident with Cisco Unified Communications Manager on 7500/10K OVA (moderate call processing). MOH: 1000 held callers, 500 MOH sources, and 300-700 annunciator callers (with 1 MOH codec). Note Reduce annunciator to 300 for two MOH codecs. When Cisco IP Voice Media Streaming application is a dedicated server on 7500/10K OVA. These recommendations are specific to MOH/ANN devices. If you combine these devices with the software media termination point (MTP) and call forward busy (CFB) devices, reduce the limits to provide streams. Note Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs 617 Custom Features Performance Impact of Media Devices with Services