[Sipp-users] RTP traffic Problem

[Imen E. <ime...@gm...>]

Hello,
    I'm trying to generate 2500 concurrent calls. the caller (UAC) will
send 5 min RTP traffic using the G711 codec. The called (UAS) will respond
with 4.5 min RTP traffic using the G729 codec. The caller and the called
are runing on the same VM. I have another VM who will do the transcoding.
SIPP indicates that all calls were finished successfully.
    The problem is in the caller screen, the audio RTP out reaches only
about 4000KB/s , which is so low for 2500 concurrent calls with G711.
    Also in the called screen, the RTP out reaches only about 800 KB/s
which is again lower than the expected for 2500 concurrent calls with G729.
    The VM CPU is normal approximately 25%, and the transmitted traffic is
approximately 6 MebiBytes which is lower than the expected again.
    Are there some settings in SIPP that might be limiting throughput? Is
it because of my VM capacity and configuration?
    I’d appreciate any insights or suggestions.
 Setup:
* SIPP Version : SIPp v3.7.3-TLS-SCTP-PCAP-SHA256.
* Caller Command: sipp -sf
/sipp/uac/lte-sp-c01-uac-173-5MinRTP-ConcurrentCall.xml -inf
/sipp/uac/a-numbers-5minRTP-concurrent-calls-from-header.csv -inf
/sipp/uac/b-numbers-1.csv -inf
/sipp/uac/a-numbers-5minRTP-concurrent-calls-pai-header.csv -cid_str
%u-lte-sp-c01-uac-65-%p@%s -deadcall_wait 10000 -watchdog_reset 10000 -r
1000 -rp 1000 -l 2500 -m 2500 -i <local-ip> -p <local-port> -mi <local-ip>
-min_rtp_port 10000 -max_rtp_port 20000  -trace_err <remoteIP:RemotePort>
*  Called Command : sudo /opt/linxa/bin/sipp -sf
/opt/linxa/lib/sipp/uas/lte-sp-c01-uas-174-5minRTP.xml -deadcall_wait 10000
-watchdog_reset 10000 -i <local-ip> -p <local-port> -mi <local-ip>
 -min_rtp_port 20000 -max_rtp_port 30000
* Caller Scenario: Custom XML with <exec
rtp_stream="sipp/uac/rtp_G711_A.wav,-1,8,PCMA/8000"/>  for infinite
playback, followed by a 5-minute timer (<pause milliseconds="300000"/>) and
then RTP pause.
* Called Scenario:  Custom XML with <exec
rtp_stream="sipp/uac/rtp_G729.G729,-1,18,G729/8000"/>  for infinite
playback, followed by a 4.5-minute timer (<pause milliseconds="270000"/>)
and then RTP pause.
* Environment: VM with 28 vCPUs, 25% CPU usage during test, monitored via
bmon.
* RTP Settings: Using defaults SIPP RTP settings.