[squeak-dev] Recover image from core dump?

Previous Topic Next Topic
 
classic Classic list List threaded Threaded
4 messages Options
Reply | Threaded
Open this post in threaded view
|

[squeak-dev] Recover image from core dump?

David Farber
Does anyone on the list know if it is possible to reconstruct an  
image from a core dump?  The core file is in standard ELF format.  My  
data is clearly in there, but I don't know enough about ELF to know  
how to re-stitch everything together.  And would a re-stitched image  
be usable (i.e. valid)?

If that approach simply won't work, does any one have any ideas/
suggestions on how I can go about retrieving object data directly  
from the core dump itself.  There are three Collections worth of data  
(we're talking 10s of kilobytes, less than 500 individual ojects)  
that I need to retrieve.

Yeah, I *really* need to get this data.

Thanks,
David
--
David Farber
[hidden email]


Reply | Threaded
Open this post in threaded view
|

[squeak-dev] Re: Recover image from core dump?

Andreas.Raab
Do you have plenty of memory? Then load the core dump into the
interpreter simulator, set its start/end address correctly, call
saveImageFile.

Cheers,
   - Andreas

David Farber wrote:

> Does anyone on the list know if it is possible to reconstruct an image
> from a core dump?  The core file is in standard ELF format.  My data is
> clearly in there, but I don't know enough about ELF to know how to
> re-stitch everything together.  And would a re-stitched image be usable
> (i.e. valid)?
>
> If that approach simply won't work, does any one have any
> ideas/suggestions on how I can go about retrieving object data directly
> from the core dump itself.  There are three Collections worth of data
> (we're talking 10s of kilobytes, less than 500 individual ojects) that I
> need to retrieve.
>
> Yeah, I *really* need to get this data.
>
> Thanks,
> David
> --
> David Farber
> [hidden email]
>
>
>


Reply | Threaded
Open this post in threaded view
|

Re: [squeak-dev] Re: Recover image from core dump?

David Farber
I've got 2G of memory on my physical machine.  The core dump is just  
under 200M (from a ~40M image).  Will I need to start Squeak with  
extra memory?  How do I determine the correct start/end address?  And  
it looks like the bits of the original process is split into a whole  
bunch of chunks in the core dump.  Will the interpreter simulator be  
able to handle that?

Thanks,
David

On Apr 1, 2009, at 3:31 PM, Andreas Raab wrote:

> Do you have plenty of memory? Then load the core dump into the  
> interpreter simulator, set its start/end address correctly, call  
> saveImageFile.
>
> Cheers,
>   - Andreas
>
> David Farber wrote:
>> Does anyone on the list know if it is possible to reconstruct an  
>> image from a core dump?  The core file is in standard ELF format.  
>> My data is clearly in there, but I don't know enough about ELF to  
>> know how to re-stitch everything together.  And would a re-
>> stitched image be usable (i.e. valid)?
>> If that approach simply won't work, does any one have any ideas/
>> suggestions on how I can go about retrieving object data directly  
>> from the core dump itself.  There are three Collections worth of  
>> data (we're talking 10s of kilobytes, less than 500 individual  
>> ojects) that I need to retrieve.
>> Yeah, I *really* need to get this data.
>> Thanks,
>> David
>> --
>> David Farber
>> [hidden email]
>
>


Reply | Threaded
Open this post in threaded view
|

[squeak-dev] Re: Recover image from core dump?

Andreas.Raab
David Farber wrote:
> I've got 2G of memory on my physical machine.  The core dump is just
> under 200M (from a ~40M image).  Will I need to start Squeak with extra
> memory?  How do I determine the correct start/end address?  And it looks
> like the bits of the original process is split into a whole bunch of
> chunks in the core dump.  Will the interpreter simulator be able to
> handle that?

I don't think it will and I can't tell you how to figure out the base
address of the image either. But I do think that if you can figure this
out you can stitch together a virtual image file that you read into the
interpreter and have the interpreter doing any magic that you need,
including extracting your data or conceivably writing out a new image
file. I've never done any of it myself but I think this is your best
option here if you really need the data as desperately.

Cheers,
   - Andreas