Why is default value of NKPT so small? mfsroot
Gary Jennejohn
gary.jennejohn at freenet.de
Sat Nov 7 10:09:38 UTC 2009
On Fri, 6 Nov 2009 11:19:51 -0800 (PST)
Trever <anti_spamsys at yahoo.com> wrote:
> Does anyone know what the thinking is behind the default value of NKTP in /usr/src/sys/i386/include/pmap.h?
>
Seems to be based on the maximum amount of usable memory. If you define
PAE then it's set to 240.
For AMD64 it's set to 32.
> Which leads me to two more questions:
> - is it possible to change the NKTP value without recompiling the kernel? I think there isn't but I'll ask.
No.
> - is it possible to change the NKTP value without editing pmap.h (can I pass a variable into the kernel build process)?
>
Well, the header files all semm to have "#ifndef NKPT" in them. Try doing
"NKPT=xxx;export NKPT" before compiling the kernel and see what happens.
---
Gary Jennejohn
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