RAID?

BenJ · 21 Jun 2007 at 13:30

Hey guys,

Been reading a lot of posts lately that talk about the speeds of using two harddrives in "Raid"

Im not familiar with this and was wondering if someone could explain it a bit

Thanks.

Teaf · 21 Jun 2007 at 13:34

In a nutshell, it's 2 or more hard drives working in parrallel to improve speed, improved fault tolerance or both! They are basically linked together with a driver that fools windows into thinking it's a single drive, but it's really 2+ drives. Raid0 is normally the most common for gamers and enthusiats because you only need 2 drives and it improves performance overall, but it's very risky because if one of the drives dies or the array is corrupted, you loose all the data that was on the drives (which is where Raid5 comes into play).

Check up on Wikipedia. People could explain it, but really it's more or less just gonna say what's already there

and if you have questions about it, post back!

BenJ · 21 Jun 2007 at 13:39

Ok ta, ill have a look at what wiki has to say.

BenJ · 21 Jun 2007 at 13:47

Ok read wiki, didnt really gain much from it.

Basically I use my pc for gaming. So you mention RAID0 is a usual.

What gains does it produce?

Is everything faster, or are some things faster and others slower?

Teaf · 21 Jun 2007 at 14:25

In terms of RAID0 benefits, you will get a lot faster read times from your drives due to 2+ of them working together. In a real world example it would speed up loading in games by a reasonable margin (but see below). But with RAID0 as mentioned, if one drive fails then the other fails with it. It won't increase FPS at all however, it just makes accessing data a lot faster than it would have been normally. An example could be that say one of your drives has about 65 MB/s reading speed on average, now if you took another duplicate drive, turned it into a RAID0 array then you would probably be looking at around 110-120MB/s average reading speed.

In regards to loading times in games, it will depend however if the game requires data to be uncompressed before it's used. Games that don't require decrompressing of data will speed up, but when you start adding decrompression of game data into the mix, then you are moving onto write speeds and also more emphasis onto your CPU speed. Whilst you would still see an improvement, you would see more of an improvement in games with pre-decompressed data. Your write speeds are increased with a striping (RAID0) and tend to get better depending on the stripe size used.

BenJ · 21 Jun 2007 at 16:19

ok, sounds like i will be getting a couple of 80gig hard drives and then joining them in raid0, and see what comes of it.

sidefxv1 · 21 Jun 2007 at 16:29

Of course there have been a few fairly trustworthy folk saying that it really gains you very little; other than some sense of achievement that you've done it (and worse MTBF

) Have a read here:

http://www.anandtech.com/storage/showdoc.aspx?i=2101&p=11

(I run raid 0... but tbh I don't know why I did it in the first place,

)

jbloggs · 21 Jun 2007 at 16:43

Also have a read at This

BenJ · 22 Jun 2007 at 12:05

After reading that one document it makes it sound like a complete waste of time

Mr-White · 22 Jun 2007 at 12:21

Understanding RAID

complete waste of time ? it actually gives you a performance gain, the more drives you have the less it saves to each one.

MW

helmutcheese · 22 Jun 2007 at 13:03

Raid0 is not a waste of time esp with 2 new Raptors (forget older ones), its not only for games as its been proven games dont benifit as much as they used to due to faster loading times from better coding, Raid0 also is good for large file work like say RAW Photos in Photoshop or even more so in Video Editing, I can tell you once you have ran 2 them drives you wont go back to any 7200rpm driver ever.

BenJ · 22 Jun 2007 at 13:21

If I do go down the raid road it will be with 7200 drives not the raptors

helmutcheese · 22 Jun 2007 at 13:41

Well as Raid0 gives 60% gains (rule of thumb), you will see 85-100MB/Sec instead of 50-65MB. (most new Sata 7200rpm drives get speeds in this region)

sidefxv1 · 22 Jun 2007 at 14:30

helmutcheese said:
Well as Raid0 gives 60% gains (rule of thumb), you will see 85-100MB/Sec instead of 50-65MB. (most new Sata 7200rpm drives get speeds in this region)

Benchmarks always look much better on RAID, but I'm still skeptical about the actual gains a user would notice in everyday use. The only reviews I've seen where someone has actually set out to measure the performance gains in real applications, the gains have been negligible.

helmutcheese · 23 Jun 2007 at 04:03

For me Unraring Archives is 1 gain:

I am on new PC but I had 2 Raptor X's wasted on a PCI bus (133MB/Sec) set up in Raid0, I got about 108MB/Sec over 78.4MB/Sec single drive use (remember I wont score as well as old PCI bus is shared with other mobo parts wont ever see 133MB/Sec on HDD's.

Anyhow, if I grab a movie at the normal 700MB size if its properly split up in .rars (yes there is a wrong way to do it) I can unrar the .AVI from the rars in 9 Secs, if its a TV EP at normal 350MB, I can unrar it in 4 secs, I am not sure what I will get now on this new mobo with PCI-E bus and both my Raptors in Raid0 as Im on a older test HDD for now messing with XP+XP64+Vista etc.

I know a guy in the States who job is testing hardware, he is very smart and used to fix the machines that make AMD wafers, anyhow he told me what I already partually knew about the HDD being the bottleneck of todays PC, it wont matter if you have the best 2CD and 4GiG ram and a 8800 Ultra if the HDD's are slow, your PC will feel slow (will obv game ok as you wont need 50-120MB/Sec for gaming).