Few RAID0 Questions

[Christo]

been posting here like a mad man lately

just thinking if i was to get two Western Digital Raptor Hard drives
(10000rpm) both 74 GB drives

slapped them on a RAID0 (im a raid newbie never used it, i just read a
introduction) it would make the two drives appear as one yes? so 148 GB
drive would be visible

after creating the array and then re starting and i proceed to install the
OS

will windows XP setup see one drive (148 GB) or will it still see 2 74 GB
drives

im gonna assume it should see one and if it sees two then the array fecked
up somewhere.

also would i notice an improvement in performance? I mean would it be faster
because it would already be with pretty wuick hard drives i believe raptors
are the fastest SATA drives available at 10 thousand RPM quicker than
standard 7200rpm drives

so would having these on a raid0 make it super fast?

also about creating partitions on the raid

would i be able to use programs such as partition magic to create partitions
on the 148GB raid as i would a standard single drive?

finally if i wanted to wipe the array i would do that through the controller
interface?

im not exactly sure how it works but i gather it appears at boot, will
detect both the drives on the SATA channels and will the ask me to press
"f6" or whatever could be "f5" for all i know to create an array or enter
RAID setup or RAID utility?

am i right in thinking that?

once in the RAID setup or RAID utility i just choose the RAID i want, RAID0,
RAID1 or RAID0/1 in this case RAID0

it does its thing

i re boot, i install windows on what should now appear as one 148GB hard
drive

hey presto

I should really do it on my next system for myself but been a bit reluctant
to embrace SATA still using old school ATA at the mo, must get with the
times

any help appreciated and thanks in advance

 

[John]

On Sun, 20 Feb 2005 23:38:56 -0000, "Christo"

Ive been doing chores and havent slept all night. Im almost wacky at
the moment from lack of sleep. Im doing some PC stuff now so Im here
to answer anything I can. Im sure to conk out anytime soon.

been posting here like a mad man lately


will windows XP setup see one drive (148 GB) or will it still see 2 74 GB
drives

One big HD.

also would i notice an improvement in performance? I mean would it be faster
because it would already be with pretty wuick hard drives i believe raptors
are the fastest SATA drives available at 10 thousand RPM quicker than
standard 7200rpm drives

People have posted the Anandtech article in other newsgroups if you go
to his site in fact he tests TWO raptors ! His conclusion was - dont
do it. He says flat out in the final words segment. He points out
itll seem blindingly faster when you do artificial benchmarks but has
negligible impact in real world usage, He even does a test loading up
some games like Far Cry I think. He also says it increases the chance
of data loss if one of the two disks dies , the whole thing is gone.

Raptors are super fast to begin with so you dont really need Raid.

am i right in thinking that?

Yeah theres a thing in bios where you set up a few parameters . I did
it with two WDs for the hell of it. And then I took them out of the
raid config after reading Anands article.

 

[Christo]

On Sun, 20 Feb 2005 23:38:56 -0000, "Christo"

Ive been doing chores and havent slept all night. Im almost wacky at
the moment from lack of sleep. Im doing some PC stuff now so Im here
to answer anything I can. Im sure to conk out anytime soon.


One big HD.


People have posted the Anandtech article in other newsgroups if you go
to his site in fact he tests TWO raptors ! His conclusion was - dont
do it. He says flat out in the final words segment. He points out
itll seem blindingly faster when you do artificial benchmarks but has
negligible impact in real world usage, He even does a test loading up
some games like Far Cry I think. He also says it increases the chance
of data loss if one of the two disks dies , the whole thing is gone.

Raptors are super fast to begin with so you dont really need Raid.



Yeah theres a thing in bios where you set up a few parameters . I did
it with two WDs for the hell of it. And then I took them out of the
raid config after reading Anands article.

oh well

i was just a bit curious about how good it would be with two raptors, i
guess ill stick to 1, they are a bit too pricey for me to be going out
buying for experiments sake


I did read that having the load of read/write being spread over two drives
and over two SATA channels would increase overall performance by 30% or
something like that

but like you say... the data loss issue, if one did go FUBAR they both would
need re formatting, i was just thinking of ways to get speedy operation,
think ill go hunt that article you were on about

cheers again John Smith lol (thats gotta be a psuedoname, if thats how you
spell that word)

 

[kony]

been posting here like a mad man lately

just thinking if i was to get two Western Digital Raptor Hard drives
(10000rpm) both 74 GB drives

slapped them on a RAID0 (im a raid newbie never used it, i just read a
introduction) it would make the two drives appear as one yes? so 148 GB
drive would be visible

after creating the array and then re starting and i proceed to install the
OS

will windows XP setup see one drive (148 GB) or will it still see 2 74 GB
drives

It sees one drive. Be sure to hit F6 during installation to
load the RAID driver via floppy. You will see the prompt to
do so.

im gonna assume it should see one and if it sees two then the array fecked
up somewhere.

yes, but it's pretty hard to mess it up, in the RAID setup
menu it should be obvious.

also would i notice an improvement in performance? I mean would it be faster
because it would already be with pretty wuick hard drives i believe raptors
are the fastest SATA drives available at 10 thousand RPM quicker than
standard 7200rpm drives

so would having these on a raid0 make it super fast?

If the RAID controller is integral to the southbridge, yes.
If it's a separate chip on the PCI bus, no.

also about creating partitions on the raid

would i be able to use programs such as partition magic to create partitions
on the 148GB raid as i would a standard single drive?
Yes


finally if i wanted to wipe the array i would do that through the controller
interface?

Depends on what you mean by "wipe". It is treated like a
single drive, whatever you want to do. IF you want to
delete the array then that is done in the RAID bios menu.
If you simply wanted to format it, there is no need to
delete the array, unless you didn't want the array any more,
then there is no sense in formatting it before deleting it.

im not exactly sure how it works but i gather it appears at boot, will
detect both the drives on the SATA channels and will the ask me to press
"f6" or whatever could be "f5" for all i know to create an array or enter
RAID setup or RAID utility?

am i right in thinking that?

Yes you'd hit a key to enter the RAID config screen.

once in the RAID setup or RAID utility i just choose the RAID i want, RAID0,
RAID1 or RAID0/1 in this case RAID0

it does its thing

You'd choose a stripe size too. generally smaller sizes are
better for OS, larger for (large files) other uses.

any help appreciated and thanks in advance

It is prudent to have a backup of all data on a RAID0 array
even moreso than another storage alternative, especially
since the drives can only be read in their array(ed) state
on similar/same controller. For example, if set up on a Via
southbridge, you can't read them, recover the data from a
Silicon Image or Promise controller if your motherboard were
to fail.

 

[Christo]

It sees one drive. Be sure to hit F6 during installation to
load the RAID driver via floppy. You will see the prompt to
do so.


yes, but it's pretty hard to mess it up, in the RAID setup
menu it should be obvious.


If the RAID controller is integral to the southbridge, yes.
If it's a separate chip on the PCI bus, no.

so basically if it is onboard integrated as it is mostly when you buy SATA
motherboards? and by PCI you mean a seperate controller card, not "built-in"

 

[kony]

so basically if it is onboard integrated as it is mostly when you buy SATA
motherboards? and by PCI you mean a seperate controller card, not "built-in"

Current-gen motherboards do have SATA via southbridge, but
the prior generation(s) used separate chip, often Silicon
Image. By "PCI" I mean a separate chip, whether it be
soldered to the board or on a PCI card is irrelevant in this
context. "Built it" on a separate, soldered-on chip is
logically (and performancewise) the same as it'd be on a
PCI-slotted card... could even be same chip, as you can
usually buy a PCI card with same chip as those that were
used on descreet onboard solutions though sometimes the
onboard used "lite" bios because it was cheaper to license
(typical with Promise solutions).

 

[Paul Murphy]

oh well

i was just a bit curious about how good it would be with two raptors, i
guess ill stick to 1, they are a bit too pricey for me to be going out
buying for experiments sake


I did read that having the load of read/write being spread over two drives
and over two SATA channels would increase overall performance by 30% or
something like that

but like you say... the data loss issue, if one did go FUBAR they both
would need re formatting, i was just thinking of ways to get speedy
operation, think ill go hunt that article you were on about

Or you could really get the bank manager worried and buy 4 of the drives -
with such a setup you could use RAID 10 (aka RAID 0+1) which offers the best
of both worlds - i.e. the speed increase of RAID 0 and the redundancy of
RAID 1. With this arrangement if 1 drive should fail you can simply swap out
that drive for a new one and the RAID setup will automatically restore data
content back to the drive as it was before the failure (without any data
loss). I'm using a RAID 10 setup with a 3Ware Controller card on my home
server and so far so good.

Paul