I had similar issues before with an Atheros WiFi card and its buggy madwifi drivers. It is likely to be a hardware issue, or even more likely a hardware-driver interaction.
Look for similar issues with your network cards and drivers, try replicating the same load in packets per second with something else (eg. ping), analyze interrupt vector allocation (no options like irqpoll to the kernel?), look in ethtool if you aren't mission some offloading feature your card support, or on the other hand, you might try turning any offloading off, it might as well help. Tomas Vondra -----Original Message----- From: Rafael Pola [mailto:rafap...@gmail.com] Sent: Saturday, April 30, 2011 1:35 AM To: sipp-users@lists.sourceforge.net Subject: [Sipp-users] Ksoftirqd consuming 100%(software interrupt) when sippreaches 350 simultaneos calls with media Hi, I am doing some performance tests using two DeLL R410 Servers(8GB of RAM, 300GB disk space and 2x 2.6GHz Intel Quad Core processors). The OS is Fedora Core 13 64 bits. The environment is: Both servers behave as sipp server and sipp client. It is for simulating high media traffic incoming and outgoing through the same server. Each server has two network physical ports. One as sipp server and other one as sip client. Each port is in a different subnet. So the Server A's sipp client reaches the Server B's sip server in a subnet network. In the other subnet the Server B's sipp client reaches the Server A's sip server. I am having trouble when it reaches about 350 simultaneous calls in both ways. The ksoftirqd process reaches 100% of CPU (software interrupt in the 'top' command) and them the network cards start to drop packets. If I start the test in just one way I can reach 1000 simultaneous call that no packets are dropped by the interface. It happens only if I test with high traffic in both ways. I tried to change the buffer_size, increase the numbers of sockets in addition use other Operating system (CentOS 5.5 - 64bits) but the issue persisted. Has anyone ever experienced it? I would appreciate any comments about. Thanks in advance, Rafael Pola ------------------------------------------------------------------------ ------ WhatsUp Gold - Download Free Network Management Software The most intuitive, comprehensive, and cost-effective network management toolset available today. Delivers lowest initial acquisition cost and overall TCO of any competing solution. http://p.sf.net/sfu/whatsupgold-sd _______________________________________________ Sipp-users mailing list Sipp-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sipp-users ------------------------------------------------------------------------------ WhatsUp Gold - Download Free Network Management Software The most intuitive, comprehensive, and cost-effective network management toolset available today. Delivers lowest initial acquisition cost and overall TCO of any competing solution. http://p.sf.net/sfu/whatsupgold-sd _______________________________________________ Sipp-users mailing list Sipp-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sipp-users
