kernel panic with memory disks

[Kris Kennaway]

On Wed, Aug 22, 2007 at 09:56:05AM +0300, Stefan Lambrev wrote:

> >No, you should use -o swap.  Where did it tell you to change the
> >sysctls?
> >
> >Kris
> >  
> Nowhere just guessing.

OK, often not a good idea :)

> I just needed one big file in the memory to ignore the slowness of hard 
> drives, to run few small benchmarks :)
> I did this using tmpfs, but it act just like "-t swap" :)

Yes, when you don't have enough RAM to do the thing you want.

> Btw the confusion comes from the manual of mdconfig where it states:
> 
> swap     Swap space is used to back this memory disk.
> 
> and I thought that type swap is always stored on the hard drives.
> 
> and md(4) explains it a lot better:
> 
> swap     Backing store is allocated from buffer memory.  Pages get pushed
>              out to the swap when the system is under memory pressure, 
> other-
>              wise they stay in the operating memory.  Using swap backing is
>              generally preferable over malloc backing.

OK, that could certainly be improved.  Can you please submit a PR?

Kris