[Mono-devel-list] Assembly Unloading

[Jim Purbrick]

Hi Zoltan,

Now that Sebastien has helped make the security
situation clearer, I think unloading assemblies is
(hopefully) the last big issue I need to resolve.

I've had a look at mono_assembly_close and it looks
like it might be OK to just call that to get rid of
the assmembly for a script. Referenced assemblies
won't be unloaded, but as scripts should only be
referencing library assemblies, which can stay loaded,
that seams OK.

Looking at the other things that mono_domain_free does
hightlights some issues which might be more
problematic. It seems to go through trashing vtable,
class info, static data and jit output hash tables.
Presumably if I wanted to unload an assembly I'd need
to selectively remove the data relating to the
assembly from these hash tables. Is there a way to
find out which entries relate to the assembly I want
to unload?

In the case of LSL assemblies there is no static data,
which might make things easier, although there will
presumably be class info and jit output. Could I use
the mechanisms used by DynamicMethod to manage the
collection of JIT output? Would that just leave me
class info to clean up? Given that I know which class
I want to get rid of would that be easy enough to
find?

Is this a reasonable approach to take? Is there
anything else I need to think about? Should I just use
separate domains for each of the (1000s) of scripts?
Should I just implement Richard's suggestion of saving
the scripts, destroying the domain and then loading
the ones I need again to clear out the assemblies and
JIT output?

Thanks for all your help,

Cheers,

Jim.


		
___________________________________________________________ 
How much free photo storage do you get? Store your holiday 
snaps for FREE with Yahoo! Photos http://uk.photos.yahoo.com