[Vm-dev] microsecond timing for GC work

[Andreas Raab]

David T. Lewis wrote:
> On Tue, Jan 19, 2010 at 10:54:35AM -0800, John M McIntosh wrote:
>> Also the ioSecond primitive has been based on localTime versus  time() as per the Unix VM code below. 
> 
> And this is a Very Bad Thing if you want to support time zones with
> daylight savings transitions.

How so? I must be missing some background here, could you elaborate?

> Lex Spoon suggested 10 years ago that we should have a primitive
> that answers UTC time plus time zone offset in a single call. He
> was right, and I guess somebody (tm) should do something about that
> one of these days.

I fail to see what that achieves.

> The Smalltalk epoch is ambiguous in Squeak, so it would be better to
> use the more clearly defined Posix epoch. Conversion to Squeak epoch
> is trivial as long once you decide what time zone the Squeak epoch
> occurred in.
> 
> Would anyone object to the addition of a primitive that answers
> Posix seconds (to some reasonable precision) plus time zone offset?
> This would be a named primitive in addition to John's microsecond
> primitive.

I'm not sure what the point of it would be. Both of you are speaking in 
riddles at this point; it would be good if you could spell out the 
issues more clearly.

Thanks,
   - Andreas