PDA

View Full Version : RAID 0 [no proformence increase]



RedOctober
8 Jul 2010, 08:38pm
I recently installed two (Western Digital Caviar Black 640GB 7200 RPM) hard drives in RAID 0 (stripped array).

I have seen the consolidation of the two drives into one and increase in storage size, up to 1.6 tb, but I have experienced absolutely no increase in performance.

My windows user experience on windows 7 was the same as when I had just one WD hard drive installed [5.9] The only reason its a 5.9 is because my disk transfer rate is so low it drags the rest of my system down.

I thought a RAID 0 would remove this bottleneck?

Any suggestions on why I see no improved performance?

KScorp
8 Jul 2010, 09:16pm
One reason might be the size of the stripes. I'm no expert on RAID, but if you have a large stripe size, that means many of your smaller files end up staying whole anyway. You end up with no performance gain. (There is a balance to selecting stripe size.)

The other possibility is your drives simply don't get that big of a boost. Last I checked, performance gains vary from drive to drive.

Lastly is what you use to get your RAID set up. It's possible whatever you use to create the array isn't very good at it. Most people use the RAID utility in their motherboard, so maybe yours isn't up to the job.

Of course, those are only things I can name off the top of my head when I was exploring RAID as an option. Someone else might be able to pinpoint a different problem.

Jager
8 Jul 2010, 09:18pm
it depends on several factors, such as hardware or software raid, but if 0 isnt cutting it, you might try raid 2 or 3 for better bandwidth

http://en.wikipedia.org/wiki/RAID if you want more info.

RedOctober
8 Jul 2010, 10:02pm
thanks for the input. I did a hard drive test with the program HD Tach.

I was wondering if this a good result?

average read: 163.6 MB/s
http://www.steamgamers.com/forum/picture.php?albumid=246&pictureid=2180

RedOctober
9 Jul 2010, 10:16am
bump.

I e-mailed my computer engineering professor from college and he told me this:

"As I understand, Windows Experience Index will top out most platter drives with a rating of 5.9 regardless of configuration. Realistically, these drives in a RAID 0 should be getting higher scores than that. But I can't fault WD for a Microsoft thing. Just another reason to not put too much stock in these scores."

But I still am curious about whether an average read of 163.6 MB/s for a RAID 0 setup is good. This is my first experience with RAID.

tinkerbell
9 Jul 2010, 03:12pm
the majority of a single hdd not in any sort of raid will top out between 60-90MB/s for sequencial read average, depending on the make and model, hence the raid controller can access more than 1 hdd at the same time, in theory you set up should read twice as fast as 1 hdd. as the graph shows your getting an average of 163.6MB/s. even some expensive solid state drives at the moment cant do that. (driver problems within the ssd) so performance wise you will see a good improvement in loading times and be able to open up programs quicker etc.. as it reads it faster from the hdd's. the down side of using raid0, is that if one of your hdd's fail, your fucked. you will lose all your data, music, films, games, porn, programs etc.. and will not be able to recover them, if your insistant on using raid 0 for a performance increase, if you can, buy another 2 identical hdd's the same as the ones you got atm, and RAID them in 1+0 a.k.a RAID10 it has the same perfomance of which you've got now in raid 0 but it mirrors them onto the other hdd's so if one of the hdd's crashes, it wont take out all you data.



tl:dr version.

yes tis good