Subject: Re: Increasing VM limits
To: Wolfgang Solfrank <>
From: Perry E. Metzger <>
List: port-amd64
Date: 02/02/2005 13:21:42
Wolfgang Solfrank <> writes:
> one of the reasons to run on amd64(-compatible) processors is the
> possibility to use much larger address spaces.  However, our current
> port doesn't support this ;-(.
> AFAICT, the only reason for this is the brain-dead linker in the Xserver,
> which insists on doing its own dynamic linking instead of using dlopen
> Turns out that it's quite easy to work around this, by simply removing the
> -DUseMMAP in src/x11/Xserver/hw/xfree86/loader/Makefile.  With this change,
> I'm running the system quite happily with a 16 GB MAXDSIZ, albeit I'm
> getting some strange "sbrk: grow ### failed, error = 12" message from
> the kernel when mallocing beyond about 12 GB (not yet investigated,
> probably will do so tonight).
> Anyone objecting to removing this UseMMAP and upping MAXDSIZ to, say
> 8 GB for now?

What does the UseMMAP define do exactly?