kernel panic with swap zone exhausted, increase kern.maxswzone

My computer recently paniced and broke into ddb after spamming my
console with "swap zone exhausted, increase kern.maxswzone"
Immediately prior to the panic X was killed and I was able to switch
to vty1 and log in as root (I planned on killing runaway programs)

I called doadump and have the saved textdump, vmcore.0 and kernel
available to provide any relevant information. They are fairly large
so I'll provide them upon request.

I'm running FreeBSD radar 9.0-BETA2 FreeBSD 9.0-BETA2 #0 r225471M: Mon
Sep 12 20:43:44 EDT 2011
eitan_at_radar:/usr/obj/usr/src/head/sys/EADLER  amd64

This is the diff between my kernel and GENERIC:
http://people.freebsd.org/~eadler/files/diff-my-kernel-and-generic.diff

gdb> bt
#0  doadump (textdump=0x31d622d0) at /usr/src/head/sys/kern/kern_shutdown.c:260
#1  0xffffffff802ea54c in db_fncall (dummy1=Variable "dummy1" is not available.
) at /usr/src/head/sys/ddb/db_command.c:572
#2  0xffffffff802ea881 in db_command (last_cmdp=0xffffffff80e5a6c0,
cmd_table=Variable "cmd_table" is not available.
)
    at /usr/src/head/sys/ddb/db_command.c:448
#3  0xffffffff802eaad0 in db_command_loop () at
/usr/src/head/sys/ddb/db_command.c:501
#4  0xffffffff802ecc19 in db_trap (type=Variable "type" is not available.
) at /usr/src/head/sys/ddb/db_main.c:229
#5  0xffffffff807731f1 in kdb_trap (type=0x3, code=0x0, tf=0xffffff8231d62500)
    at /usr/src/head/sys/kern/subr_kdb.c:631
#6  0xffffffff809c0e36 in trap (frame=0xffffff8231d62500) at
/usr/src/head/sys/amd64/amd64/trap.c:590
#7  0xffffffff809ab5df in calltrap () at
/usr/src/head/sys/amd64/amd64/exception.S:228
#8  0xffffffff80772f9b in kdb_enter (why=0xffffffff80aec7a0 "panic",
msg=0x80 <Address 0x80 out of bounds>)
    at cpufunc.h:63
#9  0xffffffff8073db00 in panic (fmt=Variable "fmt" is not available.
) at /usr/src/head/sys/kern/kern_shutdown.c:599
#10 0xffffffff807836f8 in propagate_priority (td=0xfffffe011de2a000)
at /usr/src/head/sys/kern/subr_turnstile.c:222
#11 0xffffffff80784842 in turnstile_wait (ts=0xfffffe006685e900,
owner=0xfffffe011de2a000, queue=0x0)
    at /usr/src/head/sys/kern/subr_turnstile.c:738
#12 0xffffffff8072ed16 in _mtx_lock_sleep (m=0xfffffe00804100f8,
tid=0xfffffe01c2425460, opts=Variable "opts" is not a
vailable.
)
    at /usr/src/head/sys/kern/kern_mutex.c:447
#13 0xffffffff8072ee20 in _mtx_lock_flags (m=Variable "m" is not available.
) at /usr/src/head/sys/kern/kern_mutex.c:203
#14 0xffffffff80740443 in sigexit (td=0xfffffe01c2425460, sig=0xb) at
/usr/src/head/sys/kern/kern_sig.c:3269
#15 0xffffffff80741ed0 in postsig (sig=Variable "sig" is not available.
) at /usr/src/head/sys/kern/kern_sig.c:2765
#16 0xffffffff8078210b in ast (framep=0xffffff8231d62c50) at
/usr/src/head/sys/kern/subr_trap.c:232
#17 0xffffffff809ac639 in doreti_ast () at
/usr/src/head/sys/amd64/amd64/exception.S:674
#18 0x000000000060aa10 in ?? ()
#19 0x0000000801063000 in ?? ()


-- 
Eitan Adler