[Vm-dev] [Pharo-dev] Image crashing on startup, apparently during GC

[Esteban Lorenzano]

hi,

> On 24 Mar 2018, at 09:50, Cyril Ferlicot D. <cyril.ferlicot at gmail.com> wrote:
> 
> Le 23/03/2018 à 21:52, Eliot Miranda a écrit :
>> Hi Damien,
>> 
>> Indeed the image is corrupt at start-up.  See below.
>>  
>> 
>> Right.  This VM is prior to the bug fixes in VMMaker.oscog-eem.2320:
>> 
>> Spur:
>> Fix a bad bug in SpurPlnningCompactor.
>>  unmarkObjectsFromFirstFreeObject, used when the compactor requires more
>> than one pass due to insufficient savedFirstFieldsSpace, expects the
>> corpse of a moved object to be unmarked, but
>> copyAndUnmarkObject:to:bytes:firstField: only unmarked the target. 
>> Unmarking the corpse before the copy unmarks both.  This fixes a crash
>> with ReleaseBuilder class>>saveAsNewRelease when non-use of cacheDuring:
>> creates lots of files, enough to push the system into the multi-pass regime.
>> 
>> 
>> Pharo urgently needs to upgrade the VM to one more up to date than 2017
>> 08 27 (in fact more up-to-date than opensmalltalk/vm commit
>> 0fe1e1ea108e53501a0e728736048062c83a66ce, Fri Jan 19 13:17:57 2018
>> -0800).  The bug that VMMaker.oscog-eem.2320 fixes can result in image
>> corruption in large images, and can occur (as it has here) at start-up,
>> causing one's work to be irretrievably lost.
>>  
> 
> Hi Eliot,
> 
> I think that there is a lot of people who would like to get a newer
> stable vm for Pharo 6.1 and 7. The problem is that it is hard to know
> which VM are stable enough to be promoted as stable.
> 
> Some weeks ago Esteban tried to promote a VM as stable and he had to
> revert it the same day because a regression occurred in the VM.
> 
> If you're able to tell us which vms are stable in those present at
> http://files.pharo.org/vm/pharo-spur32/ and
> http://files.pharo.org/vm/pharo-spur64/ it would be a great help.
> 
> Even better would be for the pharo community to have a way to know which
> vms are stable or not without having to ask you.

there is no “stable” branch in Cog, and that’s a problem.
“released” versions (the version you can find as stable) are not working for Pharo :( 

I tried to promote versions from end feb and that crashed. 

next week I will try again, maybe now they are stable enough… one thing is true: the versions that we consider stable (from oct/17) present problems that are already solved on latest. 

Esteban


> 
> Have a nice day.
> 
>> 
>> -- 
>> _,,,^..^,,,_
>> best, Eliot
> -- 
> Cyril Ferlicot
> https://ferlicot.fr
>