Explain RAID 1 to me please

[tigersty1e]

1. Is RAID 1 okay to use in home computers for gaming?

2. If I have 2 500GB drives in RAID 1, does that mean I only have ~500GB of storage?

3. Do both drives have to be the same capacity? For instance, I have a 20 gig drive as the master and then another 80 gigger. Can I only use 20 gigs of the 80 for RAID 1 and use the 60 leftover as storage?

4. Is RAID really only for servers? Would I better off using 1 500 gigger for normal use and just backup the data to the other 500 gigger?

 

[RebateMonger]

1. Is RAID 1 okay to use in home computers for gaming?
YES

2. If I have 2 500GB drives in RAID 1, does that mean I only have ~500GB of storage?
YES

3. Do both drives have to be the same capacity? For instance, I have a 20 gig drive as the master and then another 80 gigger. Can I only use 20 gigs of the 80 for RAID 1 and use the 60 leftover as storage?
YES

4. Would I better off using 1 500 gigger for normal use and just backup the data to the other 500 gigger?
PROBABLY. RAID adds complexity and can actually DECREASE reliability, especially with low-end RAID controllers. Backups to a second drive are "safer" than a RAID 1 array, especially if backing up to an external or offline drive. You just have to be sure that you are actually DOING the backups, though, which is an issue for most folks.

My advice to home users is:
Get a backup system first. After that, if you have spare money and time, consider a RAID array.

 

[Zepper]

I always understood that if you use different sized drives, any left over on the larger one was unavailable for other use. Because the drives in an array are treated by Win as a single drive.

.bh.

 

[f4phantom2500]

Originally posted by: Zepper
I always understood that if you use different sized drives, any left over on the larger one was unavailable for other use. Because the drives in an array are treated by Win as a single drive.

.bh.

this is my understanding as well.

 

[Matthias99]

Originally posted by: Zepper
I always understood that if you use different sized drives, any left over on the larger one was unavailable for other use. Because the drives in an array are treated by Win as a single drive.

.bh.

Depends on the controller, but on cheaper ones (like the onboard ones on many motherboards) this is frequently the case. I certainly wouldn't count on it. With software RAID through the OS you can normally create other partitions on the drive and use them normally.

For a home user, backups are generally a better idea. RAID1 doesn't protect you against any number of screwups or bad things that can happen besides a single hard drive failing.

 

[ForumMaster]

Originally posted by: tigersty1e
1. Is RAID 1 okay to use in home computers for gaming?

Yes

2. If I have 2 500GB drives in RAID 1, does that mean I only have ~500GB of storage?

Yes

3. Do both drives have to be the same capacity? For instance, I have a 20 gig drive as the master and then another 80 gigger. Can I only use 20 gigs of the 80 for RAID 1 and use the 60 leftover as storage?

No. You'll only get 20GB of storage and the rest will be unavailable, atleast with any onboard controllers.

4. Is RAID really only for servers? Would I better off using 1 500 gigger for normal use and just backup the data to the other 500 gigger?

RAID 1 constantly write to both drives at the same time. This puts equal strain on both drives. a better solution is to backup your data every 1-2 weeks on to the second drive which should rest outside of the computer in an external enclosure.

You could use something like Acronis True Image to copy your main drive to your backup drive every weekend.

 

[Roguestar]

http://en.wikipedia.org/wiki/RAID_1#RAID_1

 

[Sunner]

Originally posted by: Matthias99

Originally posted by: Zepper
I always understood that if you use different sized drives, any left over on the larger one was unavailable for other use. Because the drives in an array are treated by Win as a single drive.

.bh.

Depends on the controller, but on cheaper ones (like the onboard ones on many motherboards) this is frequently the case. I certainly wouldn't count on it. With software RAID through the OS you can normally create other partitions on the drive and use them normally.

For a home user, backups are generally a better idea. RAID1 doesn't protect you against any number of screwups or bad things that can happen besides a single hard drive failing.

Yes indeed.
RAID for reliability.
Backups for data protection.

Unless time lost from a crash with a subsequent reinstall and data restore on a new drive is a major concern for you, backups will be a superior solution, and if it is a major concern for you, chances are your data is important enough that you should have a backup of it anyway.

 

[xxeonn]

Going with RAID 1 is good if you want to secure your data but I think RAID 0 is better for gaming as you essentialy double the bandwitdh to your drives and you still get a terabite of storage.

 

[ch33zw1z]

Originally posted by: xxeonn
Going with RAID 1 is good if you want to secure your data but I think RAID 0 is better for gaming as you essentialy double the bandwitdh to your drives and you still get a terabite of storage.

hehehe

edti: anyone else feel like raining on his parade?

 

[Sunner]

Originally posted by: ch33zw1z

Originally posted by: xxeonn
Going with RAID 1 is good if you want to secure your data but I think RAID 0 is better for gaming as you essentialy double the bandwitdh to your drives and you still get a terabite of storage.

hehehe

edti: anyone else feel like raining on his parade?

I'm somewhat tempted, but also kinda tired...

 

[ch33zw1z]

Originally posted by: Sunner

Originally posted by: ch33zw1z

Originally posted by: xxeonn
Going with RAID 1 is good if you want to secure your data but I think RAID 0 is better for gaming as you essentialy double the bandwitdh to your drives and you still get a terabite of storage.

hehehe

edti: anyone else feel like raining on his parade?

I'm somewhat tempted, but also kinda tired...

ditto, that reply is all I could mentally muster.

 

[Roguestar]

Originally posted by: ch33zw1z

Originally posted by: Sunner

Originally posted by: ch33zw1z

Originally posted by: xxeonn
Going with RAID 1 is good if you want to secure your data but I think RAID 0 is better for gaming as you essentialy double the bandwitdh to your drives and you still get a terabite of storage.

hehehe

edti: anyone else feel like raining on his parade?

I'm somewhat tempted, but also kinda tired...

ditto, that reply is all I could mentally muster.

^

 

[BladeVenom]

Originally posted by: xxeonn
Going with RAID 1 is good if you want to secure your data but I think RAID 0 is better for gaming as you essentialy double the bandwitdh to your drives and you still get a terabite of storage.

Enjoy your 1% increase in game load times. Link

 

[LikeLinus]

I'm assuming most of your concerns are if you run an OS from RAID 1.

What if the RAID 1 is only for storage? I grabbed (2) 320GB 7200.10 from that Frys deal and I want to RAID 1 those drives for file storage.

What if my first HD, RAID or motherboard went bad, could I just grab that second drive and plug it up to any computer to get the data?

 

[RebateMonger]

Originally posted by: LikeLinus
What if my first HD, RAID or motherboard went bad, could I just grab that second drive and plug it up to any computer to get the data?

It depends. If only one hard drive failed, then your system should keep running.

If the RAID controller or motherboard failed, it MIGHT wipe out data on both hard drives. Or the drives might be fine.

With some RAID 1 controllers, you can remove a single drive of a RAID 1 array and hook it to a standard controller on another PC and read the data.

 

[ManBearPig]

i just mirror my data...which i'll hazard. i know i can get a virus/problem that will transfer over, but i have pretty good security and the files i mirror aren't typically targeted by viruses etc.

 

[Comdrpopnfresh]

RAID 1 supposedly increases read times. Because as write times are increased with 0, the same process is observed on 1. I believe this is why a mixture of 0+1 is best because you write faster, and read faster as well. Although, unless you have very fast drives already, there isn't much reason for RAID. The performance increase isn't worth the risk in most cases (because it is so small. Unless, I guess, you had a couple i-RAMs in raid- that'd be insanely fast, and redundancy isn't an issue since ram doesn't drastically fail often. But I have a new question to bring up. Do you see any performance increases- theoretical or real world with JBOD? If one fails are you just a screwed as with RAID0? I was thinking of getting a 320gig drive, but have a 250 in my computer now, so I wouldn't want to loose space on the 320, so I was leaning towards JBOD for one unified drive.

 

[xxeonn]

http://www.anandtech.com/showdoc.aspx?i=1491&p=2

 

[grumpyboy]

i heard raid 1 is a bit waste full one whole drive is used just for redundancy. raid 5 only uses 10 percent for redunacy.
Back the guys here right RAID should not be used as a primary backup method

 

[Sunner]

Originally posted by: grumpyboy
i heard raid 1 is a bit waste full one whole drive is used just for redundancy. raid 5 only uses 10 percent for redunacy.
Back the guys here right RAID should not be used as a primary backup method

RAID-5 will use 1 disk for parity data, so in the "worst case" scenario of three disks, you'll use 1/3 of your total space for parity, assuming no hot spares.
As you increase the amount of disks, this will go down.
So saying "RAID-5 uses xx percent for parity" is an inherently faulty statement.

 

[grumpyboy]

Originally posted by: Sunner

Originally posted by: grumpyboy
i heard raid 1 is a bit waste full one whole drive is used just for redundancy. raid 5 only uses 10 percent for redunacy.
Back the guys here right RAID should not be used as a primary backup method

RAID-5 will use 1 disk for parity data, so in the "worst case" scenario of three disks, you'll use 1/3 of your total space for parity, assuming no hot spares.
As you increase the amount of disks, this will go down.
So saying "RAID-5 uses xx percent for parity" is an inherently faulty statement.

you know if funny you say that since ive always heard raid 5 uses at least one disk parity.

But then I found this raid calculator. which is linked on wiki which is scary.

But ive double checked and your right a, RAID-5 set of N disks leaves N-1 times the space of each disk for storage

But you also said this changes as the raid gets bigger how much by?

 

[grumpyboy]

better data " Depending on the RAID level the parity will either be on one disk or be spread among all the disks. Either way it is 1/5th or 20% of the space when you are utilizing five disks. Parity is 1/4 th or 25% of the space when utilizing four disks, and 1/3rd or 33% when utilizing three disks."

 

[Sunner]

Originally posted by: grumpyboy
better data " Depending on the RAID level the parity will either be on one disk or be spread among all the disks. Either way it is 1/5th or 20% of the space when you are utilizing five disks. Parity is 1/4 th or 25% of the space when utilizing four disks, and 1/3rd or 33% when utilizing three disks."

Yeah, one disk is a simplification since it's not actually one dedicated disk for parity(that would be RAID-4), but indeed, barring hot spares, it'll scale the way you described, so you get less "waste" as you increase the number of drives.
Of course, as you increase the number of drives, the likelihood of you wanting one or more hot spares increases, so...

 

[grumpyboy]