Effectively Using A RAID Disk Array

Posted Jul 12, 2009 by Jason Faulkner  

I saw an interesting post on Slashdot not too long ago where someone asked the a question regarding a RAID setup. What I found interesting was not so much their question, rather the comments from the replies.

If you are considering using RAID in your setup, this is a great thread to read. One commenter put it best:

[T]he reason for using RAID is NOT as a backup. RAID != Backup.
RAID is for redundancy and performance increases.

This is a great point. RAID will protect you from drive failures but is not a backup solution as if you lose your data on one drive, you have lost it on all of them.

Personally, I don’t see a need for an end user machine to really have a RAID setup as it is expensive and not cost effective for performance gains when compared to better hardware.

Does anyone have any personal experience or thoughts on this?

Which Of These Traits Applies To YOUR Computing Life?...

8 Responses to “Effectively Using A RAID Disk Array”

  1. trendless says:

    RAID has many different implementations: 0 (performance only), 1 (redundancy only), 5 (a bit o’ both), 6, 10, 01, and a whole host of nested varients. Since quite a few full-size ATX motherboards (ie decent quality, non-entry-lvl) pack software RAID functionality into their SATA controllers, RAID 0, 1, and sometimes even 5 aren’t any more costly than an extra hard drive or two. RAID 0 is great for a gamer looking for extra performance, or a photoshop/video-editing/CAD/3D-modeling pro for the same reasons;. However, because there are two or more drives involved, the odds of experiencing physical drive failure is higher, so a separate backup solution is a must. RAID 1 is a perfect backup solution, especially for a business that relies on the uptime of their computer(s); everything is mirrored in realtime, so if the main drive goes down, you can run on the secondary (mirrored) drive while you get a replacement. I use RAID 5 on my server — to take advantage of some extra performance AND some redundancy (just in case). One caveat that isn’t often explored in articles about RAID: unless you have a dedicated hardware RAID card (that does the processing of redundancy etc onboard), your CPU will be on the hook for the extra calculations that are part of any RAID setup and you may well encounter varying levels of performance degradation.

    Wikipedia has several great articles that explain the technical ins-and-outs of RAID, as well as the various configurations. And ,lord knows, there aren’t a shortage of DIY (and professional) geeks on the internet who’ve gone into great detail about their setups, including some walkthroughs that might help someone unfamiliar with RAID get started.

  2. ray smith says:

    i just built my first gaming computer with a xfx nvidia nforce 790i ultra sli board. it is raid complyant. so here is the question from a gamers point. what is faster, one 150gb raptor or two 74gb running together? this is not redundancy, you are reading and writing to both at the same time. it is all about speed. yes or no? if yes then i can see a place in it for gaming. p.s. only running one at this time.

    • Sinan Saday says:

      You wouldn’t see any gains in gaming. What you would say gains in [albeit minor] is stuff like 3D Rendering, Video Editing/Exporting, and copying heavy amounts of data. For something like gaming, it wouldn’t make any difference, as gaming is all about focusing on the here and now.
      It’s the same with having a faster internet connection and MP Gaming. As an example; where I live, the standard DSL for about 80% of the country [which is smaller than a couple of USA's larger state's] is 3mb down, and so long as your connection is of good quality, your ISP has good DNS/DHCP server’s and your contention is low, you’ll be keeping up with the big boys running on 20mb cable. I’d say an extra 2mb [making it 5mb] would be put to good use on gaming, while the other 15 is just sitting there, idle essentially.

      Just remember, gaming is all about improving what’s going on during that second, and improving upon the quality of everything involved, and RAID0 makes next to no difference

      • Doug says:

        It really depends on what one calls “gains”. For example, I have RAID0 with 3 disks and my games load faster than when I didn’t have an array. Finishing a phase or scenario and loading the next one is also faster. In games that have wide open evironments, like Oblivion, new areas load faster and smoother. And that’s real gain I could feel.

        I agree that, once all details of your game were already loaded into physical memory, you shouldn’t care much about disk access speed. But for startup and loading time you will see real gains using RAID.

  3. BobHereYo says:

    I rely on weekly backups and online backups from Carbonite but I have a lot of business files that I need to archive and keep for extended periods of time so I employ a RAID 1 external hard drive for storage. I use a NexStar enclosure with two 1 TB drives so if one drive goes out I can put another 1TB drive in place for recovery purposes.

    The main point that I use that RAID external is that i have been there blown that with external drives as storage and some for backups that just fizzle out and stop working. The technology is made to fail as you have written here in a number of articles.

  4. I use Mozy to back up my data online. I use Raid 0 to mirror my working drive on my machine. This gives me two lines of defense. First when my drive fails I can just swap it out and keep working. Downtime a couple hours max. If my business were destroyed by fire or tornado and I had to start over I could start with a new computer and download my data files from Mozy and not be totally out of business. Downtime probably several days. Replace all of the software that I use on a regular basis weeks.

    This scenario uses Raid as my first line of defense and online backup as my fall back worst case position.

    As most of us know rebuilding the operating system and program files is a time consuming process that I would prefer to avoid if at all possible. The data is irreplaceable so I need that extra insurance of the off site backup for it.

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