Subject: Re: /tmp in swap
To: Jenkins, Graham K [IBM GSA] <Graham.K.Jenkins@team.telstra.com>
From: Manuel Bouyer <bouyer@antioche.lip6.fr>
List: port-sparc
Date: 12/26/2000 20:27:17
On Mon, Dec 25, 2000 at 03:39:45PM +1100, Jenkins, Graham K [IBM GSA] wrote:
> Guys (and others) - I have been playing with memory filesystems
> to place /tmp in swap space.  The examples in /etc/fstab.sd show:
>   /dev/sd0b /tmp mfs rw,-s=20000  0 0
> 
> That's OK - but what if you have multiple swap partitions and
> wish to spread /tmp over all of them?  Perhaps ..
>   swap      /tmp mfs rw,-s=20000  0 0  ??

/dev/sd0b isn't used, only to get a default geometry if needed.
MFS uses pageable memory, which is swapped out using the same rules as user
memrory. If you have several swap parttiions with equal priorities, paging
will be spread across all of them.

> 
> And what if you leave out '-s=20000'?  Depending on OS version
> it seems that half memory size - or half total swap - is assigned?

Donn't know, isn't this mentioned in the mount_mfs man page ?

--
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
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