[vdr] Re: vdr 1.3.18 cCondWait::SleepMs (was: vdr 1.3.18 with subtitles and ttxtsubs plugin)

[Darren Salt <linux@youmustbejoking.demon.co.uk>]

I demand that Mattias Gronlund may or may not have written...

[snip]
> I have been trying to find a better description of the 2 ms limit in
> nanosleep other then the man-page for nanosleep under BUGS in Fedora Core
> 2.

>     As some applications require much more precise pauses (e.g., in  order
>     to  control  some  time-critical hardware), nanosleep is also capable
>     of short high-precision pauses. If the process is scheduled under a
>     real-time policy like SCHED_FIFO or SCHED_RR, then pauses of up to 2 ms
>     will be performed as busy waits with microsecond precision.
[snip]

From nanosleep(2) (manpages-dev 2.01-1 in sarge):

  Old behaviour
    In order to support applications requiring much more precise pauses
    (e.g., in order to control some time-critical hardware), nanosleep would
    handle pauses of up to 2 ms by busy waiting with microsecond precision
    when called from a process scheduled under a real-time policy like
    SCHED_FIFO or SCHED_RR. This special extension was removed in kernel
    2.5.39, hence is still present in current 2.4 kernels, but not in 2.6
    kernels.

-- 
| Darren Salt | d youmustbejoking,demon,co,uk | nr. Ashington,
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