RAID 5 poor performance

[ssmokee]

Actually, i would run the OS (after making a back up so you can trash the OS often and keep clean) in RAID 0 and save work product to regular partitions. Remember, since this isn't true RAID, the info is stored across all disks and if one disk dies, all (including your backup) will die with it.

I dont see the point of putting the OS on a RAID 0 array. RAID 0 sacrafices integrity for speed, and for simple file serving duties the OS drive is rarely going to be accessed (other than at bootup). A hardware RAID card would be a nice idea also, but again I would have to say there isnt much point. Since its just a file server the CPU is going to be idling most of the time anyway, why not use it for calculating parity data? A RAID card that actually offloads the parity calcs from the host CPU cost $200-$300 at the low end. Motherboards with onboard SATA/PATA RIAD (or cheap ~$50 PCI RAID cards) do not offload, they still rely on the host CPU for parity calcs. Personally I think that money could be better spent somewhere else.

Edited June 8, 2005 by ssmokee

[LiquidSage]

Well, I use RAID O for my OS for speed boost. It makes every operation faster of course! What i have done is install windows and all updates - install software that i use regularly - Merge reg info into the registry for other programs i don't use often - Apply reg tweaks and personal prefs for all programs and profiles.

I then make a recovery zone w/ TI 8 and activate the boot loader on that HD. After a disk check and defrag, i make an image in secure zone and viola1 Now I have an OS backup image for raid with all i require and optimized for pure speed. I save everything on to separate basic disks for the reliability and portability.

I really care about my work product and i like the idea of connecting just 1 disk w/ whatever i need to different computers and to various connections (usb/firewire). Also raid recovery is a pain so i don't even trust a raid 1 to be easy recovery.

With the OS going at a sig. faster level, my I/O for files on my network are extremely fast and vpn is very responsive. I also have the added benefit of trashing my OS and having my 8 gig backup of that OS restore in about 4-5 min. An occasional update to the image is no prob w/ incremental backups. Though this is ideal for a personal computer, i find it to be no less useful for my home server as well.

I am perhaps to set in my ways but i don't think home users should rely on RAID for safe backups or storage/file serving esp since home users very rarely would stress their networks or server to warrant a raid setup. Plus home servers in general get messed with more often than a business server. Installing app's and OS's doing this and that and playing with permissions and partitions would be done on a workstation and extensively tested in a proper business environment. Home users are more likely to throw caution to the wind and just try something new . Most businesses do extensive tape backups on top of RAID 5 or 0 +1, so it is not a big deal if your raid array goes downhill in that situation since you have a backup of your backup.

I'm old school in favoring a hardware based array over software. (I can install an OS on a hardware array) and you are right in that a server at home left to it's basic duties might not warrant the direction I would take. With so many different ways to go these days with RAID it comes down to a matter of preference