is RAID 0+1 faster than RAID 0 ?

[mark22uk]

Hi ,

Im setting up a PC for someone , and they have 3 maxtor 80Gb SATA HDD's.

Could anyone recommend what RAID setup would be the fastest ?

 

[imported_Kensai]

RAID 0 is essentially the fastest RAID.

 

[biostud]

you need 4 harddrives for 0+1

 

[Bar81]

DO NOT use RAID 0 unless you like increased risk of data loss. The gains from RAID 0 in the real world (outside of video editing HUGE files and the like) is nonexistent. Pick up a fast boot drive and if you're truly worried about your date use a RAID 1 (mirror) array for your data.

 

[mark22uk]

Im not really worried about data loss , as the PC will generaa=lly be used to record tv shows and films from a Digital TV card and then edit and burn them to DVD.

So once there on DVD they wont really be needed.

Anyway , my mistake , i thought you could set up RAID 0+1 with 3 drives , so if you need 4 i would have to used RAID 0.

Thanks for the replies .

By the way , which cluster size would be best ?, i know it generally depends on the size of files you'll be moving around , but from what i was reading 32k / 64k seems the optimal size ? is this right ?

 

[imported_Kensai]

Smaller is better unless you're dealing with humungo files.

 

[Ronin]

Another way to put it:

Raid 0 will show benefit in sustained data transfers only. There is no other discernible benefit to Raid 0 in a conventional environment.

 

[6000SUX]

A good way to set this machine up: dedicate one drive to being a system drive, use one for capturing video, and one for backup/storage (and optional video-editing output, greatly speeding things up). There's not really all that much of a benefit to combining two of the drives size-wise, as the person will never be working with a single file over 80GB. Also, a modern 7200RPM drive should be more than fast enough for the video capture.

 

[hippotautamus]

RAID arrays are pointless from a performance gain standpoint. RAID0 isn't even real raid, and all it does is increase your chances of losing stuff. RAID is really just for servers and workstations with important stuff on them, not TV shows..

 

[mark22uk]

I put the 3 drives in RAID 0 with a 16k cluster size heres the results :-

Drive Index = 126 MB/s

Buffered Read = 327 MB/s
Sequential Read = 153 MB/s
Random Read = 79 MB/s
Buffered Write = 239 MB/s
Sequential Write = 148 MB/s
Random Write = 117 MB/s

Average Access Time = 6 ms


With just a single drive attached the nTune Disk Performance Benchmark was :-


nVIDIA nTune Disk Performance - Read = 135
Write = 161


and with the 3 drives in RAID 0 :-


nVIDIA nTune Disk Performance - Read = 370
Write = 215

I chose to use a 16k cluster size but i could have choosen 8k , 32k , 64 , 128k.

Would any of the above cluster sizes have increased the Read/Write performance ?

 

[Blain]

DO NOT use SATA or IDE drives unless you like increased risk of data loss. :shocked:

 

[mark22uk]

Thanks for the replies , im using RAID 0 16K Cluster and im have definatly seen a performance gain when benchmarking my system .

So i guess i'll keep it like that untill i get some bigger drives , because i cant afford to mirror drives , it seems like a waste of disk space for video files , as the data is not that important to justify using half of the total storage capacity for backup.

 

[lansalot]

You could go RAID5 if your system supports it, that would give a little read performance gain, some write performance loss, but you lose a drive the system keeps going.

 

[Ronin]

Why did you use a 16k cluster size, if I may ask?

 

[MobiusPizza]

Since you are dealing with large video files you might like 32k for cluster size

 

[bob4432]

why do you care about benchmarking when all you are doing is burning them to dvd? all you need is to make sure your hdds can keep up with your burner....

 

[MobiusPizza]

Yes indeed. Even the slowest HDD around now can burn DVD at 16X without problems

 

[IEC]

With 3 drives it's difficult to RAID... you need a fourth for 0+1

 

[mark22uk]

The PC will generally be used to record tv shows and films from a Digital TV , NOT ONLY record TV shows and films.

Its very simple :-

1 - The motherboard supports RAID , it has 8 SATA RAID ports.

2 - I have 3 x 80Gb SATA drives.

3 - I want to get the best Read/Write performance my motherboard and HDD can provide.


They dont care about data loss or anything like that, and there is no real reason for picking a 16k cluster size other than the fact someone suggested smaller is better.