Search the Community

Hi I have a strange problem and I'm at a loss to solve it. I've been tweaking at the settings for a while but nothing seems to improve. I have tried servers from all over the world and even moved to the non-standard ports. I did find moving to a non-standard port gave a bit of an average boost so I was more able to sustain up near the 10M max rate continuously than before. I assume this is just because most clients are connected to 443/udp and there's the OpenVPN single thread issue on the server. I am on a 24/1 ADSL2 connection with ~180ms latency to the closest LA servers. I can get slightly better latency into Singapore, but I'd rather terminate in the USA since most of my traffic ends up there anyway. What I see is that I cannot exceed about 10Mbps. I started out assuming it was just because my desktop OS is shit and its TCP window handling was slowing me down. I used DownloadThemAll to open dozens of connections instead of single-streaming a download. That didn't help. I was still capped at 10MBPS. I didn't see heavy CPU usage in my router but I ruled it by terminating the VPN on my high end i7 machine (with AES-NI) and repeating the DownloadThemAll test. It didn't help. The same test off the VPN saturates my link at 24MBPS. I have a few questions... First, is anyone else using OpenVPN in a similar situation (24/1 and ~200ms latency)? Do you see acceptable performance? Second, are there any tweaks to the config that might help improve the situation? I've tried forcing the sndbuf/rcvbuf settings to 512k but found that they hinder more than help. Third, I see what looks like high uplink utilization while pulling at the 10M rate over the VPN. the 1M uplink is actually quite saturated. I don't see similar when I disable the VPN. Is this normal for openvpn? If that's the case then I'm stuffed until I can increase my uplink rate. I didn't think OpenVPN added this much overhead though. There's nothing else I can think of to work out what's going on. Any suggestions?