Skip to end of metadata
Go to start of metadata

Voice recording CPU sizing

The table below shows the supported number of simultaneous voice calls per CPU core. 

The system was tested up to 16 core servers, where 2 cores must be reserved for the OS, leaving up to 14 CPU cores for the application.

When certain features are enabled on the Recording Servers, the capacity numbers change:

  • Encryption: when storage file encryption is enabled, capacity numbers must be decreased by 10%
  • Voice quality check: when voice quality check is enabled, capacity numbers must be decreased by 15%
 Storage Codec / Network Codec
 Recorded Platform SilkG.711G.722
Skype for Business
GSM-FR (Wave)140250160
PCM (Wave)154275176
MS-ADPCM (Wave)140250160
Speex (Ogg)92165106
  G.729G.711G.722
Cisco Network Based Recording
GSM-FR (Wave)120175113
PCM (Wave)132193124
MS-ADPCM (Wave)120175113
Speex, OGG7911675
  G.729G.711G.722
IPTrade, IPC, Speakerbus*
GSM-FR (Wave)207300195
PCM (Wave)228330215
Speex, OGG137198129
  G.729G.711G.722
Cisco Proxy and Dial-in recording,
ACME Packet / Oracle,
Cisco CUBE, Sonus, MetaSwitch SBCs,
and other SIP/SIPREC recording
GSM-FR (Wave)120175113
PCM (Wave)132193124
MS-ADPCM (Wave)120175113
Speex, OGG7911675
  G.729G.711G.722
Network port mirroring based
SIP/SCCP recording
GSM-FR (Wave)170250160
PCM (Wave)187275176
MS-ADPCM (Wave)170250160
Speex, OGG112165106
  G.729G.711G.722
Avaya*
GSM-FR (Wave)207300195
PCM (Wave)228330215
Speex, OGG137198129

Numbers in red denotes default values, should be used for server sizing

Numbers only applicable when Receive-side scaling (RSS) is enabled in the OS

* Single stream recording, e.g recording channel mixing on turrets

Sample calculations

ScenarioCPU sizing
Skype for Business recording for 1000 users
  • Skype for Business uses Silk for most call scenarios
  • GSM-FR is the recommended storage codec
  • To plan for the worst case, we assume 1000 simultaneous calls (duplex streams)
  • Encryption and voice quality checks are not required
  • CPU requirement: 1000 / 140 = 8
Trader voice recording for 500 users
  • Trader voice platforms use G.711 for most call scenarios
  • Speex is the recommended storage codec for platforms where there is no built-in DTX (e.g. IPTrade)
  • To plan for the worst case, we assume 4 simplex recording streams per turret (depends on the recording channel mixing configuration)
  • Encryption and voice quality checks are both required
  • CPU requirement: 500 x 4 / (198 x 0.9* x 0.85**) = 14

 * - The performance multiplier of the Encryption service

** - The performance multiplier of the Voice Quality Check service

  • No labels