kernel panic with memory disks

[Kris Kennaway]

On Tue, Aug 21, 2007 at 10:32:45AM +0300, Stefan Lambrev wrote:
> Hello,
> 
> Eric Kjeldergaard wrote:
> >On 20/08/07, Stefan Lambrev <stefan.lambrev at moneybookers.com> wrote:
> >  
> >>Hello,
> >>
> >>I do not know if this is know behavior, and I know that 6.2 panic if the
> >>memory disk got full,
> >>but on 7-current the panic is before the disk got full.
> >>
> >>Here is what I do:
> >>
> >>mdconfig -a -t malloc -s 800m
> >>newfs /dev/md0
> >>mount /dev/md0 /mnt
> >>cp 600mb.file /mnt
> >>    
> >
> >     -t type
> >             Select the type of the memory disk.
> >
> >             malloc   Storage for this type of memory disk is allocated 
> >             with
> >                      malloc(9).  This limits the size to the malloc bucket
> >                      limit in the kernel.  If the -o reserve option is not
> >                      set, creating and filling a large malloc-backed 
> >                      memory
> >                      disk is a very easy way to panic a system.
> >-- mdconfig(8)
> >
> >  
> I really should read manuals more carefully :) Thanks for the information.
> 
> Just one more question - to prevent panic I should use "-o reserve" and 
> have to increase:
> vfs.maxmallocbufspace
> vfs.bufmallocspace

No, you should use -o swap.  Where did it tell you to change the
sysctls?

Kris