I have not been active on this list in particular (port-i386), and so
 if this should be redirected to some other netbsd related list, I would
 welcome a correction.

 We have recently experienced several kernel panics (usually at
 rather inappropriate times) on a normally stable machine. The only
 relationship between the panics and machine activity, is that they
 have increased in frequency as we have approached disk-full
 volumes approaching 50% on the largest single partion disk.


 We are running a kernel quite close to release1.1, I have changed (aside
 from deleting unneeded devices) only a few parameters in 
 vmparam.h, for reason that the default parameters produce too
 small of a space to fsck our disks at boot time. I have been shrinking
 the amount of extension of stack, data and other parameters as I 
 can, however the machine is single purpose (a very busy USENET
 news server) so there is some justification for the way it is set up.
 Here is what I have changed in vmparam.h (both in the /usr/include
 and sys versions):

> #define       MAXSSIZ         (8*1024*1024)           /* max stack size */
tepe#> diff /usr/src/sys/arch/i386/include/vmparam.h /usr/src/sys/arch/i386/include/vmparam.h.FCS |page
63c63
< #define       MAXTSIZ         (48*1024*1024)          /* max text size */
---
> #define       MAXTSIZ         (8*1024*1024)           /* max text size */
65c65
< #define       DFLDSIZ         (48*1024*1024)          /* initial data size lim
it */
---
> #define       DFLDSIZ         (16*1024*1024)          /* initial data size lim
it */
71c71
< #define       DFLSSIZ         (24*1024*1024)          /* initial stack size li
mit */
---
> #define       DFLSSIZ         (512*1024)              /* initial stack size li
mit */
74c74
< #define       MAXSSIZ         (32*1024*1024)          /* max stack size */
---
> #define       MAXSSIZ         (8*1024*1024)           /* max stack size */


 Following, is the dmesg output following one of these panics for the
 relevant version and hardware information. The stray interrupt is I believe
 a device that I accidentally re-enabled in the bios recently. The only
 active devices on the box are console, network card (ep), floppy and 
 PCI scsi controller (PC200). No other devices are in use:

NetBSD 1.1 (tepe) #2: Fri May 24 16:01:20 CDT 1996
    ilixi@tepe.tezcat.com:/usr/src/sys/arch/i386/compile/tepe
CPU: Pentium (GenuineIntel 586-class CPU)
real mem  = 66715648
avail mem = 61243392
using 840 buffers containing 3440640 bytes of memory
isa0 (root)
com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
ep0 at isa0 port 0x300-0x30f irq 10: aui/utp address 00:20:af:18:d6:67
npx0 at isa0 port 0xf0-0xff: using exception 16
pc0 at isa0 port 0x60-0x6f irq 1: color
fdc0 at isa0 port 0x3f0-0x3f7 irq 6 drq 2
fd0 at fdc0 drive 0: 1.44MB 80 cyl, 2 head, 18 sec
root device eisa not configured
pci0 (root): configuration mode 1
pci0 bus 0 device 0: unknown vendor/product: 0x8086/0x122d (class: bridge, subclass: host, revision: 0x02) not configured
pci0 bus 0 device 7: unknown vendor/product: 0x8086/0x122e (class: bridge, subclass: ISA, revision: 0x02) not configured
ncr0 at pci0 bus 0 device 11
pci_map_mem: mapping memory at virtual fa002000, physical faff0000
pci_map_int: pin A mapped to line 12
ncr0: restart (scsi reset).
scsibus0 at ncr0
ncr0 targ 0 lun 0: <SEAGATE, ST51080N, 0943> SCSI2 0/direct fixed
sd0 at scsibus0sd0(ncr0:0:0): FAST SCSI-2 100ns (10 Mb/sec) offset 8.
: 1030MB, 4826 cyl, 4 head, 109 sec, 512 bytes/sec
ncr0 targ 1 lun 0: <SEAGATE, ST15230N, 0638> SCSI2 0/direct fixed
sd1 at scsibus0sd1(ncr0:1:0): FAST SCSI-2 100ns (10 Mb/sec) offset 8.
: 4095MB, 3992 cyl, 19 head, 110 sec, 512 bytes/sec
ncr0 targ 2 lun 0: <SEAGATE, ST15230N, 0638> SCSI2 0/direct fixed
sd2 at scsibus0sd2(ncr0:2:0): FAST SCSI-2 100ns (10 Mb/sec) offset 8.
: 4095MB, 3992 cyl, 19 head, 110 sec, 512 bytes/sec
pci0 bus 0 device 12: unknown vendor/product: 0x10a8/0x0000 (class: display, subclass: VGA, revision: 0x00) not configured
biomask 1040 netmask 400 ttymask 12
changing root device to sd0a
stray interrupt 7
panic: kmem_malloc: mb_map too small
syncing disks... <3>mb_map full
10 10 8 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 giving up

  Any help or suggestions are much, much appreciated.


 Regards,

 CEM


--
C. Ewen MacMillan

E-mail: ilixi@tezcat.net
Phone:  (312)850-0181