Use the DSP Usage window to view DSP resource usage statistics.

On the SBC main screen, go to Monitoring > System > Category: Hardware Status > DSP Status > DSP Usage or 
All > System > DSP Status > DSP Usage

The DSP Usage window opens. A portion of the window is shown below.

Figure 1: DSP Usage Window


The following output is displayed:

Table 1: DSP Usage Statistics

ParameterDescription
System NameThe node name.
Slot1Resources UtilizedRaw count of DSP resources (channels) in use on each slot to indicate which slots are loaded and to what extent, in case card removal/hot swap is necessary.
Slot2Resources Utilized
Slot3Resources Utilized
Slot4Resources Utilized
Compression TotalMaximum number of compression resources on the server (before loading, so this number is static). This essentially equates to the total number of G.711 resources before loading (lightest codec).
Compression AvailableActual compression resources currently available in real time. This essentially equates to the total number of G.711 resources after loading.
Compression UtilizationPercentage of compression resources in use (accounting for various codec weights). This can be calculated using the formula (Compression Total – Compression Available) / Compression Total).
Compression High Priority  UtilizationPercentage utilization of compression resources used for high priority calls on this server.
Compression Alloc FailuresRunning count of resource allocation failures due to resource exhaustion.

For each DSP codec, the table includes a  <codec> Total and <codec> Utilization column. 

The <codec> Total column indicates how many transcoding sessions the system can support for that codec to G.711.
The <codec> Utilization column indicates what percent of those sessions are actually in use.

NOTE: For compressed-to-compressed transcoding, two resources are required, one for each codec. 

The following codecs appear:

  • G711
  • G711Ss (silence suppression)
  • G726
  • G7231 (G723.1)
  • G722
  • G7221 (G.722.1)
  • G729Ab (G729A+B)
  • ECM (T.38 ECM)
  • Ilbc (iLBC)
  • Amr Nb (AMR-NB)
  • Amr Wb (AMR-WB)
  • Evrcb0 (EVRCB0)
  • Evrc0 (EVRC0)
  • Efr (EFR)
  • G711V8 (G711 V8)
  • G711Ss V8 (G711 silence suppression V8)
  • G726V8 (G726 V8 )
  • G7231V8 (G723.1 V8)
  • G722V8 (G.722 V8)
  • G7221V8 (G.722.1 V8)
  • G729Ab V8 (G729A+B V8)
  • ECM V34 (T.38 ECM V.34)
  • Ilbc V8 ( iLBC V8)
  • Opus
  • Silk8 (Silk 8KHz)
  • Silk16 (Silk 16KHz)

NOTE: For the purpose of collecting statistics, AMR-NB T.40 and AMR-WB T.140 are considered as separate codecs, and are listed in the DSP Usage List pane. For more information, refer to Show Table System and Audio Codecs


Tone TotalTotal tone resource capacity on this server.
Tone AvailableNumber of tone resources currently unused and available on this server.
Tone Utilization Percentage utilization of tone resources on this server.
Tone High Priority UtilizationPercentage utilization of tone resources used for high priority calls on this server.
Tone Alloc FailuresPercentage of tone resource allocation failures on this server.