Software RAID-5 ?

[jwilliams]

what can linux software based raid5 do for me?

[anomie]

http://www.redhat.com/docs/manuals/l...e/ch-raid.html

Level 5 -- The most common type of RAID. By distributing parity across some or all of an array's member disk drives, RAID level 5 eliminates the write bottleneck inherent in level 4. The only bottleneck is the parity calculation process. With modern CPUs and software RAID, that isn't a very big bottleneck. As with level 4, the result is asymmetrical performance, with reads substantially outperforming writes. Level 5 is often used with write-back caching to reduce the asymmetry. Array capacity is equal to the capacity of member disks, minus capacity of one member disk.

Bottom line: speed and data redundancy.