Disk 100% busy

[Brad Knowles]

At 2:06 PM -0600 2005-11-03, Dan Nelson wrote:

>  The biggest reason for going RAID-5 is that you only get 50% useable
>  capacity out of RAID 10, and at least 75% out of a RAID 5 (with a 3+1
>  layout.  With an 8+1 layout you get 88%).  If you don't need fast
>  writes, or your controller has sufficient cache to mask the write
>  penalty, RAID 5 sure holds a lot more data on the same disks.

	However, with RAID-5 you're in seriously bad shape when one of 
the disks dies.  You really need to add a hot spare to that list. 
And intelligent controllers can be used with other RAID types, too.

-- 
Brad Knowles, <brad at stop.mail-abuse.org>

"Those who would give up essential Liberty, to purchase a little
temporary Safety, deserve neither Liberty nor Safety."

     -- Benjamin Franklin (1706-1790), reply of the Pennsylvania
     Assembly to the Governor, November 11, 1755

   SAGE member since 1995.  See <http://www.sage.org/> for more info.