SOFTWARE-RAID-TIPS (was: Adaptec 7890 and RAID portIII RAID controller Linux Support)

[Beau James]

-->  >Part of the reason for this is that if you had one big array, then all the
-->  >files on that array may be residing in the first portion of the disks.  To
-->  >seek from any one file to another could be a relatively short seek.  When
-->  >you split the filesystems, then a read of a file on each filesystem will
-->  >result in a half disk seek to get from one filesystem to another.
-->  >These half disk seeks will *destroy* your overall effective performance.
--> 
--> OUCH!! This is VERY BAD news indeed :-( What you recommend is
--> virtually impossible. If you have several partitions to put in the
--> raid it'll cause an unacceptable loss of space... If you have to put
--> /, /usr, /var and /home in the raid, how many disks will you need?

Why bother breaking these directories into separate partitions,
especially if you are going to put all of them onto a RAID array?

Separate partitions is largely a historical artifact of *nix, based
on the limited size of disks.  What is the benefit of perpetuating it?

Beau

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