Public bug reported: Binary package hint: irqbalance
irqbalance-0.55-2 seems to misconfigure my Linux box. I have a Sun 4100M2 (2xdual core AMD Opteron 2216) running Ubuntu Hardy (64 bit). I have been benchmarking software that performs lots of network I/O, using 8 network cards on the box (6xe1000 2xforcedeth) With irqbalance running as a daemon, when the benchmark is under way, there are always two ksoftirqd processes running, each consuming 100% CPU. This unsurprisingly causes a massive slowdown in the benchmark. I can achieve about 4GBits of traffic in total. I've found two ways of fixing the problem: 1) Kill irqbalance completely before the benchmark runs, OR run irqbalance at bootup with its --oneshot option. 2) Downgrade to irqbalance-0.12-2 from Debian. This version chosen simply because I have used this same machine with a pure Debian installation in the past, and that was the irqbalance on there. With either of these two steps, throughput rises to about 8GBits and there are no ksoftirqd processes eating CPU. Solution 2 gives slightly better performance, presumably because irqbalance is able to move IRQs around as needed. I would prefer to have an irqbalance running, because while the benchmark has regular network traffic on all NICs, in 'real world' use this machine could have unpredictable network traffic and the initial IRQ allocations may not be optimal. Running on kernel linux-image-2.6.24-amd64-generic (various versions have failed to make a difference to the behaviour, so I suspect the problem is irqbalance-specific rather than kernel-specific) ** Affects: irqbalance (Ubuntu) Importance: Undecided Status: New -- irqbalance causes ksoftirqd to use 100% CPU https://bugs.launchpad.net/bugs/297121 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs