[MPlayer-dev-eng] threaded cache

[Scott W. Larson]

On Sun, 2011-11-27 at 20:52 +0100, Reimar Döffinger wrote:
> On 27 Nov 2011, at 20:16, "Scott W. Larson" <scowl at wballphotos.com> wrote:
> > On Sun, 2011-11-27 at 17:41 +0100, Reimar Döffinger wrote:
> >> If you set the clock from 2100 to 2011 somewhen in-between the point
> >> where you calculate the timeout and when you call pthread_cond_timedwait
> >> it will wake up in 2100.
> > 
> > Does this problem only happen when someone changes the clock?
> 
> Yes. Adjustments by NTP or similar have of course the same effect if they cannot/are not done via temporary clock speed changes. No idea if you could come up with something crazy like an overflow in the time struct that would cause it too, but that's probably too far fetched to care about.

That's a relief. Changing the clock on our customers' systems will have
far worse consequences than threads not timing out. Jobs won't be
scheduled correctly. Parts won't be ordered. Accounting will probably
not balance at the end of the month. Nightmare!

A lot of real-word business applications demand a monotonous clock.
That's why on our customers' systems changing the clock manually is as
forbidden as opening up the computer while the power is on.