Re: 1GB process size limit on sparc64

Paul de Weerd wrote:
> On Thu, Jun 03, 2010 at 10:26:57AM -0400, William Schaub wrote:
> | I may not want every process on the system sucking up 1GB or more
> | but I sure want to be able to work with more memory in a single
> | process if I need to. (what if you want to mmap a file larger than
> | 1GB?)
> 
> Well .. then you mmap a file larger than 1GB. What of it ? Have you
> tried mmap(2)'ing a file larger than 1GB ? I'm guessing you haven't...
> 
> For fun (no profit) I just mmap'ed a file that is larger than 8GB on
> my amd64 workstation (MAXDSIZ is 8G on amd64, ulimit was the default
> for staff, 524288K). I could read each and every byte from this file
> (takes ~3.5 minutes and really thrashes my lowly SATA disk).
> 
> So, yeah, you can mmap files bigger than MAXDSIZ just fine.
> 
> Cheers,

Ok granted I assumed you couldn't mmap that much only because of the 
error I was getting with trying to mount an mfs filesystem based on the 
size of one of my swap partitions. which gives back.

mount_mfs: mmap: Cannot allocate memory


Either way I do know 100% for sure that you can never malloc more than 
the small amount in MAXDSIZ. and I was just interested in know if there 
are any plans to fix that for the sparc64 port. I'm pretty sure on amd64 
you the limit is a bit higher. in fact on amd64 the define is:
#define MAXDSIZ         ((paddr_t)8*1024*1024*1024)

I will go ahead and try doing mmap anyway and see what happens.