Question about hard drive and raid speed

assassin84

Distinguished
Jul 24, 2009
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Hi guys, im looking for parts to build my self a pc and i have finally narrowed it down to just choosing the right hard drives. Now my budget for the storage system is 500$, oh and btw i work on proffesional video editing and effects for feature films and just small free lance work. I use sony vegas, the adobe suite, avid, and 3d programs like maya and 3ds max.

so I have narrowed my search down to this
1 of these http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=5239129&CatId=4357

or

or 2 of these in raid 0 http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=5201710&CatId=4357

or

2 of these http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=4545311&CatId=4357

these are strictly for my video files, i have other drives for my os and apps.

so my question is, how much speed increase do you get with raid 0, because the first drive is twice as fast as one of the other 2. so should i get the 2 with raid 0? and if i do, do i need any extra hardware to run a raid system? or do you have your own recommendations?

thanks in advance
 
Solution
For your application you will get almost no speed improvement with RAID0 while doubling your possibility of losing all data on the RAID0 array. The potential speed advantage from a RAID array is that you can be transferring data from one HDD unit's buffer to your CPU and RAM while the other unit is still seeking the data it wants from a different place, so you don't have to wait for that second data chunk to be found. But the fact is that disk speeds internally and their large buffers now mean that data are made available so fast that it is waiting in the buffer for the CPU to catch up in many cases. This is especially true when you are dealing with sequential access to a long string of sectors in a large file so that an entire disk...

Frag Mortuus

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Sep 18, 2009
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I dont really think you get any speed increase with RAID 0 at all. I JUST built my new system (a few hours ago) and all of my Windows 7 scores are 7.4 except for my disc transfer rate which is 5.9. They are all 7200RPM drives hooked up to SATA 3.0Gbps ports.

My friend has the same drives as me but without RAID and his W7 score is 6.1 for disc transfer rate.

I do like the ability to combine all discs into one large volume though!

The hardware needed to run a RAID config depends on the Motherboard you buy. If you look in the description (on the manufacturers website) it will tell you what RAID configs it supports.

On my new PC I had to go into BIOS, Select SATA configuration and tell it to read my SATA drives as RAID drives. Then I had to reboot, and hold Ctrl+I to enter the RAID setup screen. Once there, I just had to tell the PC what drives to include in the array and tell it the amount of memory to use for the drive.

I didnt need to use a floppy disc and all that jazz, which is what just about every resource on the web will tell you to do. The drivers where built right into the board.

Hopefully that helps!
 

Paperdoc

Polypheme
Ambassador
For your application you will get almost no speed improvement with RAID0 while doubling your possibility of losing all data on the RAID0 array. The potential speed advantage from a RAID array is that you can be transferring data from one HDD unit's buffer to your CPU and RAM while the other unit is still seeking the data it wants from a different place, so you don't have to wait for that second data chunk to be found. But the fact is that disk speeds internally and their large buffers now mean that data are made available so fast that it is waiting in the buffer for the CPU to catch up in many cases. This is especially true when you are dealing with sequential access to a long string of sectors in a large file so that an entire disk track or two can be read into the HDD's on-board buffer (or written) in one disk revolution. That is exactly what happens for your application - reading and writing very large files of video data, with few pauses to find the start of a different file.

For me, I'd put more weight on the costs. The 1.5 TB drives are $110 each, the basic 2.0 TB unit is $200, and the RE version of 2.0 TB with double buffer size is $310. That last one is particularly designed for 24/7 use in a server environment with a very long projected lifetime. So for $220 you could get 3.0 TB or 2.0 TB (slightly less $), and I'd go for the larger two-disk option. Now, you could do that as RAID0 but don't expect any significant speed-up, and be aware of the higher possibility of total data loss. An advantage of RAID0, of course, is that the array appears to the OS as one drive with a capacity of the total for two disks. That may not matter to you - you might be happy just using separate storage devices for groups of work. Or, if you really want one huge storage space, consider the JBOD version of RAID in which two or more HDD units can be grouped as one "drive". But remember, any RAID system also carries with it the potential problems to handle if your RAID controller (maybe the mobo if you are using built-in RAID) fails and must be replaced - poor RAID standardization means it is hard to change controllers and still read old disks.

For $500 I'd look at two options. First, working "without a net", would be to buy four 1.5 TB drives, use them as individuals, and have 6.0 TB of storage. Save the extra $100. But better, especially since you will do video work for sale to clients, is to be sure you have a reliable backup system for your files. Buy four of the 1.5 TB units and mount two in your computer. Then buy this external two-bay case:

http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=3481274&CatId=4270

and mount the other two drives in it. (For twice the price, there is also another model with more interface options and more RAID options, but I don't think you need them.) Although the only interface here is USB2 (others are faster), for use mainly as a backup unit you can tolerate slightly slower performance. Make your backups to this unit periodically (and remember to verify that the backed up data is good and actually CAN be recovered!), then disconnect it entirely from computer and wall power to isolate it. Best, even, is to store it off-site when not in use. Now you have both lots of storage AND a reliable backup system. All that's needed is will power to DO the backups. In fact, with reliable and up-to-date backups, you would be in a much better position to use RAID0 or JBOD in your main computer's pair because you will be prepared to recover from the disaster of disk failure.
 
Solution