Raid 0+1

cymatty · 3 Jul 2006 at 15:16

Ok i am a bit of n00b so i hope this is right.

I have a dfi LANPARTY UT nF4 Ultra-D mobo which has,

Serial ATA with RAID
Four Serial ATA ports
SATA speed up to 3Gb/s
RAID 0, RAID 1 and RAID 0+1
NVIDIA RAID allows RAID arrays spanning across Serial ATA and Parallel ATA

So if i want Raid 0+1 i need 4 hard drives, and two of the drives will be used for backup (drives 3+4) and drives 1 and 2 will be used in stripe? so half the data goes on each for speed increase, am i right so far.

So i i buy 4 of these hard drives Seagate ST3120813AS 120GB SATA II 7200rpm 8MB Cache it will cost around £200, will i have 240gb of storage? If so this is fine as i have a server which stores most of my files.

Finally will i notice a performance increase over my current single 160gb sata 1 HD, does anyone have a similar setup and have some HD tach results.

eggcup · 3 Jul 2006 at 22:00

cymatty said:
Ok i am a bit of n00b so i hope this is right.

I have a dfi LANPARTY UT nF4 Ultra-D mobo which has,

So if i want Raid 0+1 i need 4 hard drives, and two of the drives will be used for backup (drives 3+4) and drives 1 and 2 will be used in stripe? so half the data goes on each for speed increase, am i right so far.

So i i buy 4 of these hard drives Seagate ST3120813AS 120GB SATA II 7200rpm 8MB Cache it will cost around £200, will i have 240gb of storage? If so this is fine as i have a server which stores most of my files.

Finally will i notice a performance increase over my current single 160gb sata 1 HD, does anyone have a similar setup and have some HD tach results.

yes, yes, yes, yes and probably . In that order.

Dutch Guy · 4 Jul 2006 at 10:30

Yes on all points.

I have no experience with a RAID0+1 setup but I can imagine the read performance to be as fast as a RAID0 setup but the write performace might be a bit slower as the data has to be duplicated.

I thionk my RAID0 setup gets sustained read performance of ~110Mb in HDTach but not too sure on that one.

cymatty · 4 Jul 2006 at 12:14

I am now thinking of having 3 or 4 Hitachi Deskstar 7K80 in raid 0 as the performance seems very very good, I will keep all critical data on another drive on the pc and a backup on my server, does this seem a good idea?

Dutch Guy · 4 Jul 2006 at 12:18

cymatty said:
I am now thinking of having 3 or 4 Hitachi Deskstar 7K80 in raid 0 as the performance seems very very good, I will keep all critical data on another drive on the pc and a backup on my server, does this seem a good idea?

Speed wise that would be very fast, but the downside is that if one of the four drives dies you lose all the data so schedule very regular backups.

cymatty · 4 Jul 2006 at 12:25

Dutch Guy said:
Speed wise that would be very fast, but the downside is that if one of the four drives dies you lose all the data so schedule very regular backups.

Is there an software to monitor Hard Drive health? also all my picture music etc are on my server backed up so the only thing on my Raid array would be program files.

Dutch Guy · 4 Jul 2006 at 12:52

cymatty said:
Is there an software to monitor Hard Drive health?

All that will tell you it is healty, as soon as one drive fails you will lose everything as the data is split over 4 disks so monitoring is useless.

Have you considered getting a 2 disk RAID0 setup with two larger drives?

cymatty · 4 Jul 2006 at 13:08

Dutch Guy said:
All that will tell you it is healty, as soon as one drive fails you will lose everything as the data is split over 4 disks so monitoring is useless.

Have you considered getting a 2 disk RAID0 setup with two larger drives?

Yes i have, i looked at getting 2 of the Hitachi 250gb drives, however i dont need massive storage as it will be for program files only, the 250x2 works out at a similar price to 3x80gb and 4x80gb being £30 more, so i have to see which offers the best performance as it is clear which offers best value and figure out which is more important.

Dutch Guy · 4 Jul 2006 at 13:36

This is a review comparing a lot of different RAID levels including 2 disk RAIDo up to 4 disk RAID0:
http://techreport.com/reviews/2005q4/chipset-raid/index.x?pg=4

cymatty · 4 Jul 2006 at 13:53

Cheers for that, I have been reading reviews and have come up with this spreadsheet for comparison (not complete yet) what in your opinion looks the best from this limited info

http://www.twobeds.com/upload/userfiles/cymatty/hd.xls

Dutch Guy · 4 Jul 2006 at 14:24

Obviously in pure harddisk benchmarks a 4 disk RAID0 array will wipe the floor with everything but the difference in real programs is much smaller with the downside being 4 drives creating heat and the bigger chance of failure.

cymatty · 4 Jul 2006 at 14:30

Dutch Guy said:
Obviously in pure harddisk benchmarks a 4 disk RAID0 array will wipe the floor with everything but the difference in real programs is much smaller with the downside being 4 drives creating heat and the bigger chance of failure.

Yes I see your point, so you think 3x80gb in raid will be quick enough in real world performance, with less chance of failure and if i go for 4x80gb there is more risk of failure without a big enough speed increase over 3x80gb.

cymatty · 6 Jul 2006 at 15:08

Any more advice before i make my decision.

Beansprout · 7 Jul 2006 at 23:31

With RAID0, if one drive dies you lose everything - whereas with RAID 0+1 (don't confuse it with RAID10), you can survive one drive failure and have a small chance of surviving two. But you do need a minimum of 4 disks.

I chose a 4-disk RAID10 array for my newest server and it flies. 125Mb/sec...RAID0+1 should be around that mark.

RAID0 would be a little faster....but do you want to lose everything with a single disk failure?

cymatty · 8 Jul 2006 at 01:39

Beansprout said:
RAID0 would be a little faster....but do you want to lose everything with a single disk failure?

It wouldn't bother me to be honest i know it sounds strange so i will explain.

At my house there is only me who uses my pc, amd in my room i have a laptop, a file server and my desktop all on a LAN. My files are backed up onto my file server which runs 24/7 if i want music or videos i just stream them to either my lappy or desktop.

My desktop is my play thing i like to use it now and again (my laptop is used 95% of the time) and so i like it to be quick a noticeable steup in performance than my laptop. So the only thing that would be stored on the desktop (which is where the drives will be going) will be windows and program files, if one drive dies i have an excuse to re format.

My exsisting 160gb HD would be kept in the desktop and used to backup important files from my server so i have at least two copies of the data, and if needs be a copy could be kept on the raid array so i have a second copy or third copy of all my data from my server, hope that wasn't to long and boring just trying to make my situation understood so advice can better be given.

Beansprout · 8 Jul 2006 at 03:03

In that case go for RAID0 just to feel the speed. I suppose you can always test it for a bit and switch to RAID0+1 to compare (you'll need to reformat the array though I should think)

Energize · 8 Jul 2006 at 05:26

cymatty said:
Is there an software to monitor Hard Drive health?

Smart is probably the only thing that works.