Raid 0 Issues at DVinfo.net

Dana Rice · September 6th, 2009, 05:08 AM

I have a 2008 8 Core Mac Pro Tower... it has the stock 320 gig drive where the OS resides, a 1.5 TB Seagate in bay 2, and identical 500 GB Hitachi drives in bays 3 and 4. All drives are 7200 RPM's. I have the 2 500 GB drives in a Raid 0 Configuration with a Raid Block size of 256K. I tried copying a 4 gig movie file over to the raid from my main drive and I got read/write speeds of about 65 MB/sec for the peak... I then tried copying the same file to the Seagate and got about the exact same speeds. I was under the impression that the Raid drive should read/write considerably faster than the non-raid one. Anyone know why my Raid would be the same speed as my regular drives?

Giroud Francois · September 6th, 2009, 05:25 AM

well , if you are copying a file from a regular drive to a raid one, the bottleneck is on the regular drive, so there si few chance you can write faster to the target than you would be able to read from the source.
Raid speed is usefull when capturing high bandwith device or to move huge amount of data to or from memory.

September 6th, 2009, 05:08 AM	#1
Dana Rice Regular Crew Join Date: Mar 2008 Location: Chicago, IL Posts: 37	Raid 0 Issues I have a 2008 8 Core Mac Pro Tower... it has the stock 320 gig drive where the OS resides, a 1.5 TB Seagate in bay 2, and identical 500 GB Hitachi drives in bays 3 and 4. All drives are 7200 RPM's. I have the 2 500 GB drives in a Raid 0 Configuration with a Raid Block size of 256K. I tried copying a 4 gig movie file over to the raid from my main drive and I got read/write speeds of about 65 MB/sec for the peak... I then tried copying the same file to the Seagate and got about the exact same speeds. I was under the impression that the Raid drive should read/write considerably faster than the non-raid one. Anyone know why my Raid would be the same speed as my regular drives?

September 6th, 2009, 05:25 AM	#2
Giroud Francois Inner Circle Join Date: Feb 2004 Location: switzerland Posts: 2,133	well , if you are copying a file from a regular drive to a raid one, the bottleneck is on the regular drive, so there si few chance you can write faster to the target than you would be able to read from the source. Raid speed is usefull when capturing high bandwith device or to move huge amount of data to or from memory.