Hi, I'm running OpenVZ on a CentOS 6 x64 machine with a stable kernel (2.6.32-042stab049.6) and have even tried the issue below on the test-branch (2.6.32-042stab052.2). The issue I'm experiencing is also reported by Fredericep on the forum but never got any follow-up: http://forum.openvz.org/index.php?t=tree&goto=44238&&srch=inbound#msg_44 238
It's the exact same problem: my hardware node runs perfectly fine, it has both full in- and outgoing networking speed. I can consistently (3hours+ as tested) download files at my full line speed. Whenever I try to same in a container, I can get a quick burst of network traffic for a few seconds (10MB/s+) and then fall back to 10-200Kb/s, it varies. My first troubleshooting went to incoming traffic shaping for the eth0/venet0 interface, but that's not the case: # tc -s qdisc ls dev eth0 qdisc mq 0: root Sent 65350399 bytes 363366 pkt (dropped 0, overlimits 0 requeues 0) rate 0bit 0pps backlog 0b 0p requeues 0 # tc qdisc del dev eth0 root RTNETLINK answers: No such file or directory But this is a default install and it doesn't have any traffic shaping rules active. Neither does it have iptables active. It's all still running the default OpenVZ stack. Second idea was a possible hit of TCPSNDBUF or TCPRCVBUF as the defaults (1720320) are rather low. But even changing it to something idiotic like 9223372036854775807 didn't make a difference. The /proc/user_beancounter also didn't report any failed packets. When tcpdumping the stream, I don't see anything abnormal except that it's just slow traffic. Nothing out of the ordinary at first glance. I'm looking for any advice on how to troubleshoot this, as I believe this may very well be a CentOS 6 kernel bug - but to prove that, I would of course need to dive deeper which is where my train of thought kind of ends. I look forward to any reply/idea this list may give me. Mattias Geniar _______________________________________________ Users mailing list Users@openvz.org https://openvz.org/mailman/listinfo/users