Re: processes stuck in vmo_de state

On Thu, Mar 13, 2014 at 10:18 AM, Xin Li <delphij_at_delphij.net> wrote:
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> Hi,
>
> It looks like there is a regression (or a regression that gets exposed
> by some new feature) that is related to time-keeping or timecounter,
> although I'm not yet familiar with the related code to tell if my
> conclusion was right or not.
>
> The problem I observed is that when system boots up, it sometimes
> hangs and pressing ^T on console tells me that sleep(1) is running
> with 0 second out of 1 second, but the 'real' part of the output is
> smaller than 1 or sometimes negative.
>
> For some reason the console may stop giving any output, but trapping
> into debugger would unblock it sometimes.
>
> When sh(1) stuck in 'vmo_de' state, it would never recover from that
> and a hard reset is necessary.

If sleeps are not being serviced 'vmo_de' "deadlocks" makes sense
because it is a sleep(1) condition.
What is softclock doing at the time the deadlock happens?

Attilio


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