[WARNING!]SqueakMap problems

goran.hultgren at bluefish.se goran.hultgren at bluefish.se
Tue Nov 19 11:14:55 UTC 2002


Hi all!

Andreas.Raab at gmx.de wrote:
> Göran,
> 
> This is a problem in the UUIDGenerator. The following will trigger the
> problem reliably:
> 
> * take out the primitive from UUID>>primMakeUUID
> * start image
> * evaluate
>      UUID new.
>   (to force generator creation)
> * save image
> 
> Whenever you restart the image it will create *exactly* the same UUIDs in
> exactly the same order. The problem is that UUIDGenerator's random number
> generator is based on the millisecond clock value at the point where the generator
> is created. I think there should really be a set of randoms which are
> initialized based on different seeds (including date, time, network address etc)
> and the generator *must* be flushed when the image starts.

Ok, thanks guys. Perhaps... THIS SHOULD SAY SO IN THE CLASS COMMENT. :-)

Grrrrr.

But thanks for all the info - this makes perfectly sense - the image was
restarted around 30 Oct so it fits. It also fits with the "sequential"
behaviour.

Funny enough I actually think SM is "safe" at this moment because I
fired off 10000 UUIDs on it so it has probably "run past" the current
packages. :-)

I will see what I can do later today to:

1. Rescue all those little packages that got "misplaced"
2. Make sure it doesn't happen again.

You know - UUIDs is typically a thing you want to be able to trust...
It's sortof the whole point with them...

> Cheers,
>   - Andreas

regards, Göran




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