RAID VS single hard drive?

RAID seems all the rave but would a RAID of combined disk equalling
400GB, compared to a single 400GB hard drive be faster same slower?

I'd like to use it if I could hear some chatter.

Robert Blass wrote:
RAID seems all the rave but would a RAID of combined disk equalling
400GB, compared to a single 400GB hard drive be faster same slower?

I'd like to use it if I could hear some chatter.
It depends on the level but storing 200 Gb is the best you can do with a
RAID setup.

In message Robert Blass
was claimed to have wrote:

RAID seems all the rave but would a RAID of combined disk equalling
400GB, compared to a single 400GB hard drive be faster same slower?

I'd like to use it if I could hear some chatter.

The answer is a solid "maybe"

With a low end RAID controller, you'll go slower then a single drive,
with the controller limiting your performance.

With a decent controller, your performance should improve, although it
may not.

RAID-0 should read and write faster then a single drive. Lose a single
drive, all of your data is gone.

RAID-1 may read faster, but will never write faster. Redundant, but
suffers from 50% overhead.

RAID-10 should perform fastest of all, a good controller will read from
all four drives at once, but writes will just match RAID-0 speed, but
again, 50% overhead.

RAID-5 will generally read somewhere between a single drive and RAID-0,
although it should be pretty close to RAID-0, but writes will be even
slower then RAID-1. This has the advantage of only using one drive for
redundancy, and can tolerate one drive failure. Advanced controllers
can offer multiple drives worth of redundancy if needed.

"Robert Blass" wrote in message
...
RAID seems all the rave but would a RAID of combined disk equalling
400GB, compared to a single 400GB hard drive be faster same slower?

I'd like to use it if I could hear some chatter.



It would not bother with RAID.

Though striping may boot performance a little, it probably won't be much.
Plus if one of the drives starts to fail...data recovery can be more
difficult.

On Fri, 06 Feb 2009 00:34:04 -0500, Robert Blass wrote:

| RAID seems all the rave but would a RAID of combined disk equalling
| 400GB, compared to a single 400GB hard drive be faster same slower?
|
| I'd like to use it if I could hear some chatter.

I'm sure I'll hear if I'm wrong about this, but I always thought the original
purpose of RAID was to compensate for the lack of availability of large hard
drives. For instance, it let the user have 400GB of seemingly continuous real
estate long before a single 400GB hard drive was more than a dream.

But RAID has definite drawbacks over single drives, IMHO. The main one is the
huge overhead. RAID gives a little, but exacts a great price. Mammoth drives
are here now and are relatively cheap. Forget about RAID and keep good backups.

Larc

"MP" == Mike Painter writes:

MP Robert Blass wrote:
RAID seems all the rave but would a RAID of combined disk
equalling 400GB, compared to a single 400GB hard drive be
faster same slower?

I'd like to use it if I could hear some chatter.
MP It depends on the level but storing 200 Gb is the best you can
MP do with a RAID setup.

Geez, where does this crap come from. There are no limits to RAID.

For the OP: I run a 3-disk, 480 GB total capacity RAID 0 on my PC. A
4th identical disk serves as the boot drive, but for over a year I ran
a 4-disk RAID 0 system with the boot partition on the RAID. RAID 0 is
definitely faster than the same disks un-RAIDed. You will hear dire
warnings of reliability, but I've never had a problem, and anyway you
should be running backups to an external disk drive regardless of your
PC disk configuration.
--
You know what would make a good story? Something about a clown
who make people happy, but inside he's real sad. Also, he has
severe diarrhea.
- Jack Handey

First, you need to understand there are several different catagories of
RAID.

Just a few of the common varities,
RAID 0
RAID 1
RAID 5
RAID 10

Among your typical home user, you will probably hear mostly of RAID 0 and
RAID 1. RAID 5 and 10 and others are usually found in use on corporate
servers.

(in very simplistic terms...)

RAID 0
With RAID 0, you need a minimum of 2 drives, but the sky is the limit as to
how many you can use.
RAID 0 allows you to write and read across multiple drives at the same time.

Pros
Speed. Since you are writing and reading to multiple drives, the speed goes
up the more drives used.

Cons
Security.
Since your data is scattered across the multiple drives, if you lose any one
of the drives, you lose all the data.

Capacity
The total capacity is the sum of the drives. If you have three 500gig drives
in a RAID 0 array, your total storage is 3x500gig, or 1.5TB.


RAID 1
With RAID 1, you use two hard drives.
all your data is written and read from both hard drives at the same time
resulting in the same data on each drive. each drive is an exact copy
(mirror) of the other.

Pros
Safety. The same data is on both drives. If one of the drives fail, the
remaining drive stilll has all your data intact, alowing you to continue
operation until you can replace the failed drive.

Cons
Speed. Since you are reading/writing the same data to both drives, the speed
may suffer.

Capacity
The total capacity for two drives in a RAID 1 array is equal to the capacity
of a single drive. Two 500gig drives in a RAID 1 array gives you a total
capacity of 500gig.


Comments...
You will probably hear many gamers speaking of the increased speed of using
a RAID 0 array. That's fine as long as you understand the risk you take in
order to take advantage of the speed of a RAID 0 array. As I mentioned, with
a RAID 0 array, if asny of the drives fail, you lose ALL the data.




"Robert Blass" wrote in message
...
RAID seems all the rave but would a RAID of combined disk equalling
400GB, compared to a single 400GB hard drive be faster same slower?

I'd like to use it if I could hear some chatter.

In message Larc
was claimed to have wrote:

On Fri, 06 Feb 2009 00:34:04 -0500, Robert Blass wrote:

| RAID seems all the rave but would a RAID of combined disk equalling
| 400GB, compared to a single 400GB hard drive be faster same slower?
|
| I'd like to use it if I could hear some chatter.

I'm sure I'll hear if I'm wrong about this, but I always thought the original
purpose of RAID was to compensate for the lack of availability of large hard
drives. For instance, it let the user have 400GB of seemingly continuous real
estate long before a single 400GB hard drive was more than a dream.

That's the case with RAID-0, although you get more then just one large
volume, you also get increased performance due to striping.

But RAID has definite drawbacks over single drives, IMHO. The main one is the
huge overhead.

RAID-0 has no appreciable overhead (One cluster may be taken for the
RAID card to store it's identification data) but comes with additional
risk, if you lose one drive, you the data stored on all drives.

RAID-1 has 50% overhead, but offers the ability to have a drive fail
without downtime.

RAID-5 has at maximum overhead of 33%, but that drops depending on the
number of drives. A pair of Highpoint 2320 controllers could create an
array with as little as 6.25% overhead and still allow for a single
drive failure (not that I'd recommend creating a 16-drive RAID-5 array
mind you, but you could)

RAID gives a little, but exacts a great price. Mammoth drives
are here now and are relatively cheap. Forget about RAID and keep good backups.

Backups are only useful to a point -- Specifically, the point where you
last made a backup. Any work done since then will be lost in the event
of a primary storage failure.

Backups may also have significant recovery time after a failure, whereas
with a well designed RAID-1/5 system, drive failures don't result in any
data loss after a single failure.

In other words, depending on your needs, there is need for both RAID as
well as backups.

On Fri, 6 Feb 2009 12:00:40 -0500, "Timothy Drouillard"
wrote:

| First, you need to understand there are several different catagories of
| RAID.
|
| Just a few of the common varities,
| RAID 0
| RAID 1
| RAID 5
| RAID 10
|
| Among your typical home user, you will probably hear mostly of RAID 0 and
| RAID 1. RAID 5 and 10 and others are usually found in use on corporate
| servers.
|
| (in very simplistic terms...)
|
| RAID 0
| With RAID 0, you need a minimum of 2 drives, but the sky is the limit as to
| how many you can use.
| RAID 0 allows you to write and read across multiple drives at the same time.
|
| Pros
| Speed. Since you are writing and reading to multiple drives, the speed goes
| up the more drives used.
|
| Cons
| Security.
| Since your data is scattered across the multiple drives, if you lose any one
| of the drives, you lose all the data.
|
| Capacity
| The total capacity is the sum of the drives. If you have three 500gig drives
| in a RAID 0 array, your total storage is 3x500gig, or 1.5TB.
|
|
| RAID 1
| With RAID 1, you use two hard drives.
| all your data is written and read from both hard drives at the same time
| resulting in the same data on each drive. each drive is an exact copy
| (mirror) of the other.
|
| Pros
| Safety. The same data is on both drives. If one of the drives fail, the
| remaining drive stilll has all your data intact, alowing you to continue
| operation until you can replace the failed drive.
|
| Cons
| Speed. Since you are reading/writing the same data to both drives, the speed
| may suffer.
|
| Capacity
| The total capacity for two drives in a RAID 1 array is equal to the capacity
| of a single drive. Two 500gig drives in a RAID 1 array gives you a total
| capacity of 500gig.
|
|
| Comments...
| You will probably hear many gamers speaking of the increased speed of using
| a RAID 0 array. That's fine as long as you understand the risk you take in
| order to take advantage of the speed of a RAID 0 array. As I mentioned, with
| a RAID 0 array, if asny of the drives fail, you lose ALL the data.

RAID is one of those things I've been looking for an answer for a long time. It
is one technology I have yet to hear even a single logical reason for on a
consumer-grade computer given today's HDD capacities and prices. What if it
lets you tie three 500GB HDDs together? The best price I can find on three of
those is $180. I can buy a 1.5TB HDD for $50 less.

IMHO, RAID is something that once had a purpose for mainstream users but has now
gone the way of the horse and buggy. I can think of more valid reasons in favor
of floppy drives.

But that doesn't mean my eyes and ears are closed. I'm fully prepared to be
awed by logic if it exists for RAID on everyday computers.

Larc

On Feb 6, 12:34 am, Robert Blass wrote:
RAID seems all the rave but would a RAID of combined disk equalling
400GB, compared to a single 400GB hard drive be faster same slower?

I'd like to use it if I could hear some chatter.

Couple of 70G HDs at 15K RPM rotational speed striped together for
140G, each with its own dedicated controller and premises are
promising. Couple of caveats -- for the milage, of course: 1) buy the
exact same, manufactured model numbers when "doing" your HDs, 2) buy
manufacturer-approved RAID tolerance HDs, sic, HDs recommended for
RAID usage, 3) optionally, "live and learn." Personally, I don't do
RAID, although neither am I running records for bank accounts for the
finance company where you bank.