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Operating System Specific Discussions => Amiga OS => Amiga OS -- Development => Topic started by: Karlos on May 31, 2005, 10:44:38 AM

Title: WarpOS, PPC and ChipRAM
Post by: Karlos on May 31, 2005, 10:44:38 AM

Hi,

Can anybody confirm what the default cache setup is supposed to for the 603/604 with respect to the chip ram area?

I discovered recently (quite by accident whilst talking to Patrik about screwy performance results) that on my system it seems to be cached (copyback too), rather than non-cacheable. For writes, this slowed it down a *lot*. Allocating chip memory with AllocVecPPC() using MEMF_WRITETRHOUGH or MEMF_CACHEOFF corrected this.

This seems odd to me as I cannot think of any reason why the chip ram should be copyback enabled.

Is my installation screwy?

Title: Re: WarpOS, PPC and ChipRAM
Post by: Framiga on May 31, 2005, 11:04:35 AM

Hi Karlos

which powerpc.library are you using?

I've noticed a very different behaviour with 16.1beta1 (http://devnull.owl.de/~frank/powerpc_V16_1beta.lha) and the latest 16.1 (this one allocates a lot of RAM).

Title: Re: WarpOS, PPC and ChipRAM
Post by: Karlos on May 31, 2005, 11:13:19 AM

I'm using warpup 5.1 as found on aminet. I'll need to check after work to get the exact powerpc.library version. I think it's v16, but I am not completely sure.

Title: Re: WarpOS, PPC and ChipRAM
Post by: Framiga on May 31, 2005, 11:21:50 AM

yesy you are using the latest 16.1 (WOS 5.1 Update archive).

powerpc.library 16.1 (7-Feb-2001)

Try the 16.1beta1 and look at the differences.

I've no time now to check again but IIRC, the latest 16.1 is installed as semaphor or resident . . .don't remember now. btw . . . it eats about 2 MB of fastram.

Title: Re: WarpOS, PPC and ChipRAM
Post by: Karlos on May 31, 2005, 11:34:10 AM

Quote

Framiga wrote:

btw . . . it eats about 2 MB of fastram.

Trust me, that is not a problem ;-)

Title: Re: WarpOS, PPC and ChipRAM
Post by: Framiga on May 31, 2005, 12:09:58 PM

no, no its not a problem for me too!

The interesting thing, would be . . why? :-)

EDIT- and to understand why , its a job for you :-D

Title: Re: WarpOS, PPC and ChipRAM
Post by: Karlos on May 31, 2005, 12:26:56 PM

The library uses 2MB you mean?

It probably allocates some memory for book keeping and what not. I also know that the PPC MMU tables can use up quite a lot of ram, but I think these are already allocated even before you start WarpOS (at least on BPPC)