Re: Can't change kern.mbuf.nmbclusters on evbarm?

[Andy Ruhl <acruhl%gmail.com@localhost>]

On Thu, Jun 30, 2011 at 2:42 AM, Joerg Sonnenberger
<joerg%britannica.bec.de@localhost> wrote:
> How much memory do you have?

128 MB:

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NetBSD 5.99.53 (DOCKSTAR.JUN26_2011) #1: Sun Jun 26 14:40:55 MST 2011
        root@foghorn:/usr/obj-evbarm/sys/arch/evbarm/compile/DOCKSTAR.JUN26_2011
total memory = 128 MB
avail memory = 120 MB
sysctl_createv: sysctl_create(no_sa_support) returned 22
timecounter: Timecounters tick every 10.000 msec
mainbus0 (root)
cpu0 at mainbus0: Sheeva 88SV131 rev 1 (ARM9E-S core)
cpu0: DC enabled IC enabled WB enabled EABT branch prediction enabled
cpu0: 16KB/32B 4-way Instruction cache
cpu0: 16KB/32B 4-way write-back-locking-C Data cache
mvsoc0 at mainbus0: Marvell 88F6281 Rev. A0  Kirkwood
mvsoc0: CPU Clock 1200.000 MHz  SysClock 400.000 MHz  TClock 200.000 MHz


>The new logic is supposed to cap
> nmbclusters at 1/4 of the physical memory OR 1/2 of the KVA for
> architectures without direct memory mapping. Whatever is smaller.
> ARM has an additional limit of 64MB (NMBCLUSTERS_MAX). IIRC to avoid
> exhausting KVA for that purpose.

Between what you wrote and what was written in the previous reply, I
need to figure out how to do this math to see what's going on...

Andy