[urgent] Spur sometimes produces unloadable image segments

 
Hi everyone,

I desperately need some help with image segments in spur (Pharo). After having tested close to 1000 image segments that were written with a spur VM I have ended up with a couple that can't be loaded. I can reproducibly generate them from our old segements (Squeak 4 VM).

Without full confidence in the image segment code I can't upgrade and couldn't upgrade those few instances anyway. I would be very thankful if someone had the time to look into this quickly.

I will try to debug it myself but it will probably take me a couple of hours (if not days) until I have succeeded in building a VM that I can debug.


Cheers,
Max

 
Hi Max,

I'm not sure if it would help, but if there is a code snippet that
reproduces the failure, I can try running it on Squeak to see if it
gives any clues.

Dave

On Sat, May 30, 2020 at 07:00:29PM +0200, Max Leske wrote:

 
Hi Max,

> On May 30, 2020, at 10:00 AM, Max Leske <[hidden email]> wrote:
>
> Hi everyone,
>
> I desperately need some help with image segments in spur (Pharo). After having tested close to 1000 image segments that were written with a spur VM I have ended up with a couple that can't be loaded. I can reproducibly generate them from our old segements (Squeak 4 VM).
>
> Without full confidence in the image segment code I can't upgrade and couldn't upgrade those few instances anyway. I would be very thankful if someone had the time to look into this quickly.
>
> I will try to debug it myself but it will probably take me a couple of hours (if not days) until I have succeeded in building a VM that I can debug.

The only way this can be debugged realistically is to be able to simulate the reproducible case in the VMMaker simulator.  Is there any possibility of this working?  How big is the image in the reproducible case?  What facilities does it use (I’m guessing external imaging which as yet can’t be simulated).  If this can be made to occur headless and is hundreds of megabytes or less not gigabytes then we have a good chance of reproducing it in the simulator.

>
>
> Cheers,
> Max