[OpenBIOS] [PATCH] RFC: Increase dictionary size on SPARC64

[Artyom Tarasenko]

2010/4/14 Blue Swirl <blauwirbel at gmail.com>:
> On 4/14/10, Artyom Tarasenko <atar4qemu at googlemail.com> wrote:
>> 2010/4/13 Blue Swirl <blauwirbel at gmail.com>:
>>
>> > On 4/13/10, Mark Cave-Ayland <mark.cave-ayland at siriusit.co.uk> wrote:
>>  >> Igor Kovalenko wrote:
>>  >>
>>  >>
>>  >> > Your changes increase .bss of elf image, and that is handled by
>>  >> > entry.S automatically so no changes are needed.
>>  >> >
>>  >>
>>  >>  Okay, great :)
>>  >>
>>  >>
>>  >> > BTW do we need 512K for forth heap? It may be enough to modify openbios.c
>>  >> > setting MEMORY_SIZE to 256K and DICTIONARY_SIZE to 512k there.
>>  >> > Change to ofmem_sparc64.c does not seem to be helpful.
>>  >> >
>>  >>
>>  >>  I honestly don't know enough to make an informed choice, although my
>>  >> feeling is that since PPC has 512K (and it will obviously be enough to solve
>>  >> the problem with OpenSolaris) then it can't be too bad an option. Does
>>  >> anyone else have a feeling one way or the other?
>>  >
>>  > One possible problem may be that we overrun the 32 bit address space,
>>  > because there is only 3M available: 0xffd00000 to 0xffffffff.
>>
>>
>> Oh. I guess that's the amount stored in totmap[0].num_bytes in sparc32/lib.c?
>>  Then obp_dumb_memalloc really has too few space for loading Solaris kernel.
>>  Maybe because the memory is not freed.
>
> That's only on Sparc32, but memory could be tight there too, the
> layout is the same.
>
> There should be quite a few tricks to reduce memory consumption:
> compile with -Os, remove or make unused code conditional, optimize
> mixed C/Forth constructs like fword("xx") etc.

Right. This also explains why the code compiled with -o0 or debugging
enabled doesn't go as far as the optimized code when using
Solaris 2.5.1.
Basically the memory corruption bug I reported was at least partly produced
by the debugging method itself.

-- 
Regards,
Artyom Tarasenko

solaris/sparc under qemu blog: http://tyom.blogspot.com/