Re: [9fans] What is for 64 bit 9front?

[erik quanstrom <quanstro@quanstro.net>]

On Fri Aug  8 21:28:00 EDT 2014, cinap_lenrek@felloff.net wrote:
> for me, its the opposite. my fileserver and cpu servers
> are 32 bit machines, but i use thinkpad x230 which has
> 16gb of ram as a terminal. 64bit is just normal now on
> the pc and having huge (kernel) virtual address space
> solves problems like running out of space for devdraw
> bitmaps or having to tmpmap the page tables.

that is really a question of KZERO.  if you're running out of
space for big things in kernel space on any 32-bit terminal, and
you don't have need for processes >=3g, then just move KZERO
down to 0xc0000000.  i have verified KZERO down to 0x80000000
work.  this shouldn't be a surprise since this was KZERO until
recently.  make sure to change KTZERO in mkfile.

i run a 64 bit kernel on all my intel hardware.  it's easier to
concentrate on one kernel, and even on machines with only 4g
of memory, memory remapped above 4g to make room for
mmio like pci will be otherwise wasted.  up to 1g of memory
can be remapped.

i find it very useful to launch many large processes on cpu servers.
it's really nice to have 15gb of buffers on the file server
(with only 15 page table entries!)

- erik