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    SubjectRe: [Bug #12650] Strange load average and ksoftirqd behavior with 2.6.29-rc2-git1

    Ok, the ksoftirqd/1 stats contain a smoking gun:

    ksoftirqd/1 (2280, #threads: 1)
    ---------------------------------------------------------
    se.exec_start : 152642.614531
    se.vruntime : 57051.648140
    se.sum_exec_runtime : 5741.506722
    se.avg_overlap : 0.000000
    se.avg_wakeup : 10.000000
    se.wait_start : 0.000000
    se.sleep_start : 152642.623948
    se.block_start : 0.000000
    se.sleep_max : 22662.455146
    se.block_max : 4096.496408
    se.exec_max : 0.016849
    se.slice_max : 0.000000
    se.wait_max : 0.053862
    se.wait_sum : 7899.023463
    se.wait_count : 4235574
    sched_info.bkl_count : 0
    se.nr_migrations : 1
    se.nr_migrations_cold : 0
    se.nr_failed_migrations_affine : 32
    se.nr_failed_migrations_running : 47
    se.nr_failed_migrations_hot : 23
    se.nr_forced_migrations : 0
    se.nr_forced2_migrations : 5
    se.nr_wakeups : 4235539
    se.nr_wakeups_sync : 0
    se.nr_wakeups_migrate : 11
    se.nr_wakeups_local : 4235506
    se.nr_wakeups_remote : 34
    se.nr_wakeups_affine : 4
    se.nr_wakeups_affine_attempts : 44
    se.nr_wakeups_passive : 7
    se.nr_wakeups_idle : 0
    avg_atom : 0.001355
    avg_per_cpu : 5741.514564
    nr_switches : 4235404
    nr_voluntary_switches : 4235389
    nr_involuntary_switches : 18
    se.load.weight : 3121
    policy : 0
    prio : 115
    clock-delta : 295

    these bits:

    se.sum_exec_runtime : 5741.506722
    nr_switches : 4235404
    nr_voluntary_switches : 4235389
    nr_involuntary_switches : 18

    mean that ksoftirqd _really_ ran more than 4 million times since bootup
    - that is _highly_ anomalous. It means that scheduler clock is fine, and
    that your box is really running a lot of softirq workload.

    Here is how it should look like normally. A 16-way testbox with almost
    an hour of uptime, running high load with a lot of networking. Its CPU#0
    ksoftirqd [the busiest one] has these stats:

    se.sum_exec_runtime : 0.523552
    nr_switches : 42
    nr_voluntary_switches : 42
    nr_involuntary_switches : 0

    it ran only 42 times. That is a normal ksoftirqd pattern.

    I'll check your traces as the next step.

    Ingo


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