solving the default sizing issue

as all of us who have attempted builds lately have found the
default sizing is not sufficient.

i think we can solve most of it without re-introducing some of
the issues seen in PR#28379 by increasing the RLIMIT_AS cur
to the max, and perhaps bumping DFLDSIZ to 256MB.  the problem
there happen with far more than the 512MB that the RLIMIT_AS
max allows, and since most allocations are in the global (AS)
region, not the DATA region, it's unlikely larger DFLDSIZ helps
as much here.

ragge, what do you think?


.mrg.


Index: vax/machdep.c
===================================================================
RCS file: /cvsroot/src/sys/arch/vax/vax/machdep.c,v
retrieving revision 1.196
diff -p -u -r1.196 machdep.c
--- vax/machdep.c	11 Jun 2020 19:20:46 -0000	1.196
+++ vax/machdep.c	7 Jan 2024 19:58:03 -0000
@@ -772,6 +772,6 @@ mm_md_readwrite(dev_t dev, struct uio *u
 void
 machdep_init(void)
 {
-	proc0.p_rlimit[RLIMIT_AS].rlim_cur = DFLDSIZ;
+	proc0.p_rlimit[RLIMIT_AS].rlim_cur = MAXDSIZ;
 	proc0.p_rlimit[RLIMIT_AS].rlim_max = MAXDSIZ;
 }