Re: linux-raid compatable w/ Adaptec AIC-7902?

[Tyler <pml@dtbb.net>]

Mark Hahn wrote:

>>>>>  md0          /boot      sd[ab]1
>>>>>  md1          /          sd[ab]2
>>>>>  md2          /usr       sd[ab]3
>>>>>  md3          /var       sd[ab]4
>>>>>          
>>>>>
>...
>  
>
>>There are other reasons to use multiple partitions.  Having /home as a 
>>separate partition, e.g., allows one to reinstall without copying the data 
>>off to another machine.  It also prevents a user from filling up the root 
>>fs, which often has bad consequences.  The same goes for partitions for 
>>/tmp and/or /var.
>>    
>>
>
>one very serious problem with this approach is that each filesystem
>will probably be journaled, which means that it'll spend a lot of time
>shuttling the heads between journal and data areas.  if you have activity
>on /, /usr and /var at the same time, your heads will do little other 
>than rush madly around.  in cases where this can't be avoided (for instance,
>using quotas to eliminate the user-fills-partition problem), you can 
>often improve things markedly by turning on noatime/nodiratime.
>
>  
>
Also, depending on the file system, you can set reserved space 
percentage for root with tools such as tune2fs.

Tyler.