Hello, I've been investigating using openvpn as a tunnel initiator between to sites, and have been struggling to find the reason that performance is so poor when transmitting from an openVPN client running powerpc linux and using a PSK/tun setup.
| ppclinux | ---------- | openvpn server | ------- | FTP client | The ppclinux machine initiates a connection to the openvpn server. And the ppclinux machine hosts a vsftpd FTP daemon. In order to avoid benchmarking encryption, I have both sides specify: cipher none auth none no-replay The FTP client pushing data to the FTP server via a PUT command works fairly well, with transmit speeds in the 6-7MB/s range (the IP routed performance, with no tunnels, is about 12MB/s), however doing a "GET" results in performance that peaks around 800KB/s. The ppclinux machine looks pretty well idle while pushing out the 800KB/s, with the profiles showing that softirqs are the only big consumer of cycles, so it seems like it's some issue of the kernel copying in/out of the tun device from the openvpn server? Has anyone experienced this before? The top of the opreport is below. I looked at strace output also, and the openvpn server seems to be reading/writing ~1350 byte packets on each transmit. I tried things like swapping the openvpn server/client (no change), using the kernel's IPIP tunneling (performance is great), and moving the openvpn tunnel to be between the openvpn server and the FTP client (both x86 linux machines -- performance is great). Any ideas? Thanks, mh CPU: e500, speed 800 MHz (estimated) Counted CPU_CLK events (Cycles) with a unit mask of 0x00 (No unit mask) count 100000 samples % image name app name symbol name 63659 44.4683 vmlinux vmlinux __do_softirq 10095 7.0517 vmlinux vmlinux arch_cpu_idle 5900 4.1214 vmlinux vmlinux finish_task_switch 4179 2.9192 ath9k ath9k /ath9k 3969 2.7725 mac80211 mac80211 /mac80211 2227 1.5556 vmlinux vmlinux _raw_spin_unlock_irqrestore 1870 1.3063 vmlinux vmlinux tcp_ack 1534 1.0716 vmlinux vmlinux tick_nohz_idle_enter 1378 0.9626 vmlinux vmlinux tcp_transmit_skb 1374 0.9598 vmlinux vmlinux memcpy 1281 0.8948 vmlinux vmlinux tcp_write_xmit 1049 0.7328 oprofiled oprofiled /usr/bin/oprofiled 978 0.6832 tun tun /tun 892 0.6231 vmlinux vmlinux ring_buffer_consume 876 0.6119 ath9k_hw ath9k_hw /ath9k_hw -- Martin Hicks P.Eng. | m...@bork.org Bork Consulting Inc. | +1 (613) 266-2296 ------------------------------------------------------------------------------ "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE Instantly run your Selenium tests across 300+ browser/OS combos. Get unparalleled scalability from the best Selenium testing platform available Simple to use. Nothing to install. Get started now for free." http://p.sf.net/sfu/SauceLabs _______________________________________________ Openvpn-users mailing list Openvpn-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-users
