On 25 Jun 2000, Dave Daniels wrote:

> I have recently bought a Kinetic Card for my RiscPC and am happy
> to report that NetBSD/arm32 works fine on it. However you will
> need the 'memfix11' update from the Castle web site otherwise the
> bootloader does not work. (This is really to fix a problem with
> memory allocation for the PC Card but the bootloader needs it
> too.) To be honest I cannot say if it has had any great impact on
> the speed of NetBSD. It is hard to tell if NetBSD is using the
> faster memory or not.
> Question: does NetBSD allocate the *physical* memory from the highest
> addresses downwards or from the lowest addresses upwards? The faster
> memory is at a higher address. My RiscPC has physical memory blocks
> as follows:
>     0x10000000  4096 pages
>     0x18000000  4096 pages
>     0x20400000  7168 pages
>     0x30000000  8192 pages
> The first two are the old, 'slow' memory and the other two blocks
> are the new, faster memory on the Kinetic Card. Obviously if the
> kernel allocates memory from the low addresses then you will not
> see any improvement but if it allocates it from the high addresses
> first then things should be different. I could look though the
> source and try to figure it out for myself, but if anyone could
> provide a quick answer, I would be grateful.

	In addition to the very sage answers from people with respect
	to kernel/cache page usage, NetBSD also supports multiple free
	page lists, which is already used on mvme68k to prefer local
	memory over vmebus memory for more frequently accessed pages...
	The buffercache might be a good user of the slower memory? :)

		David/absolute
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