Chris Kantarjiev wrote:

> I am investigating using an mmap'd file for the buffer, but would also like to
> understand if I can increase the hard limit of RLIMIT_DATA. Is this being set by
> the MAXDSIZ kernel parameter? Can I "just" raise that number in vmparam.h and
> recompile, or are there some fundamental limits based on structure sizes?

For all released versions, you can use mmap (with MAP_ANON, so you
don't need a file either) to get around the limit. You won't be able
to allocate it all at once, but with 2 or 3 calls you can come close.
Changing anything in vmparam.h is a very bad idea.