Hi, I am currently doing some characterization testing to figure out the limitations of my freeswitch server. I have tried both with SIPP and by driving SIP calls between 2 Freeswitch through mod_event_socket. I get similar results both ways and I am suspicious of the results I get. Basically, whenever I try to launch calls with SIPP at a rate superior than 8 cps, it seems like calls are being stacked. The response time for a call between the "invite" and the corresponding "200 OK" keeps increasing as long as calls are being made which slows down the processing speed until the average CPS gets around 8 cps. My setup is : 1 Dual-Core AMD Opteron(tm) Processor 8216 @ 2.4 GHz 4 GB of RAM Gigabit NIC Centos 5 FreeSwitch Version 1.0.trunk (8911M) I think that my setup is underperforming and that it might be related to some missing configuration tweaks. I already adjusted the ulimit to the recommended settings in the wiki for maximum performance. I was wondering if there might be something else, that I'm still missing. Would any of you have an idea of what might be holding back my setup ? Thanks ! PG P.S. I gathered a bunch of information that I thought could be useful. Freeswitch performance settings In switch.conf.xml <!--Most channels to allow at once --> <param name="max-sessions" value="10000"/> <!--Most channels to create per second --> <param name="sessions-per-second" value="1000"/> <!-- Default Global Log Level - value is one of debug,info,notice,warning,err,crit,alert --> <param name="loglevel" value="alert"/> Here is the SIPP command I used, based on Freeswitch load_test script. # sipp -sf dft_cap.xml 192.168.100.9 -s 9990 -r 15 -rp 1000 -l 200 -d 10000 -i 192.168.100.200 -mi 192.168.100.200 # cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 15 model : 65 model name : Dual-Core AMD Opteron(tm) Processor 8216 stepping : 2 cpu MHz : 2411.121 cache size : 1024 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 2 fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt rdtscp lm 3dnowext 3dnow pni cx16 lahf_lm cmp_legacy svm extapic cr8_legacy bogomips : 4823.60 TLB size : 1024 4K pages clflush size : 64 cache_alignment : 64 address sizes : 40 bits physical, 48 bits virtual power management: ts fid vid ttp tm stc # cat /proc/meminfo MemTotal: 4042672 kB MemFree: 843188 kB Buffers: 256676 kB Cached: 2671172 kB SwapCached: 1092 kB Active: 777140 kB Inactive: 2192840 kB HighTotal: 0 kB HighFree: 0 kB LowTotal: 4042672 kB LowFree: 843188 kB SwapTotal: 2031608 kB SwapFree: 2016120 kB Dirty: 0 kB Writeback: 0 kB AnonPages: 41068 kB Mapped: 26028 kB Slab: 195536 kB PageTables: 5672 kB NFS_Unstable: 0 kB Bounce: 0 kB CommitLimit: 4052944 kB Committed_AS: 153064 kB VmallocTotal: 34359738367 kB VmallocUsed: 35492 kB VmallocChunk: 34359692283 kB HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 Hugepagesize: 2048 kB # ulimit -a core file size (blocks, -c) 0 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited pending signals (-i) 40960 max locked memory (kbytes, -l) 32 max memory size (kbytes, -m) unlimited open files (-n) 1024 pipe size (512 bytes, -p) 8 POSIX message queues (bytes, -q) 819200 real-time priority (-r) 0 stack size (kbytes, -s) 10240 cpu time (seconds, -t) unlimited max user processes (-u) 40960 virtual memory (kbytes, -v) unlimited file locks (-x) unlimited # top top - 14:31:16 up 1 day, 58 min, 2 users, load average: 5.73, 6.83, 5.36 Tasks: 129 total, 1 running, 128 sleeping, 0 stopped, 0 zombie Cpu(s): 7.0%us, 2.8%sy, 0.0%ni, 50.8%id, 38.8%wa, 0.0%hi, 0.5%si, 0.0%st Mem: 4042672k total, 3418968k used, 623704k free, 256904k buffers Swap: 2031608k total, 15488k used, 2016120k free, 2681820k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 6078 root 18 0 614m 109m 6480 S 19 2.8 3:39.11 freeswitch