Re: newfs by fstab directory name?

Wes Peters wrote:

>On Tuesday 28 October 2003 12:05, David O'Brien wrote:
>  
>
>>On Mon, Oct 27, 2003 at 01:26:23PM -0800, Wes Peters wrote:
>>    
>>
>>>At work we do a lot of dynamic filesystem creation, so we added the
>>>ability to specify the 'special file' argument to newfs via the
>>>fstab mount point directory.  Please see the attached patch.  If
>>>nobody objects, I'll commit this in a couple of days.
>>>      
>>>
>>Not objecting, but I don't follow how the change is to be used.
>>Can you post an example?
>>    
>>
>
>Sure.  Example from /etc/fstab:
>
>/dev/ad0s1d            /tmp            ufs     rw              2 2
>/dev/ad0s1f            /usr            ufs     rw              2 2
>/dev/ad0s1e            /var            ufs     rw              2 2
>/dev/acd0              /cdrom          cd9660  ro,noauto       0 0
>/dev/da0s1e            /spool          ufs     rw,noauto       0 0
>
>The disk space on /spool is managed by the "application" and isn't
>guaranteed to be on-line or even existent when the "system" portion
>loads and starts the application.  This space is entirely transient
>data that doesn't need to be saved across reboots.  When the 
>application starts, it checks to see if /spool is clean; if so it
>just mounts it, if not it newfs's it and then mounts it.  This
>space isn't necessarily always "da0s1e" but it is always "/spool"
>across different hardware platforms.  We prefer to:
>
>	newfs /spool
>
>rather than
>
>	. {some file full of shell variables describing the hardware}
>	newfs $SPOOL_PARTITION
>
>because the former is slightly more concise.  We had a local patch to do 
>this in our 4.x code base, but it seemed a general enough change that 
>others might find it useful as well.  I recall ecountering this same 
>problem at DoBox so it appears to be a general problem for disk-based 
>appliances, at least if you want to support differing hardware.
>
>  
>
This would also be useful for anyone doing any sort of benchmarking 
using data sets- I did a code port of LADDIS/SFS to Linux ages ago to do 
some NFS/SMB fileserver testing, and I can say, quite a LOT of entirely 
temporary data is generated...

Scott