sata on intel chip

  • Thread starter Thread starter Andre LaFramboise
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Andre LaFramboise

ok i found the drivers to do an install on sata 1 and sata2 ,i wantto run
them in raid 0 .
i set the bios as per the book and went in the utility and deleted old
volumes and created new ones as pre book.then poped in win xp home with sp2
and load driver for intel chip thru f6.got windows to format drives,loaded
win great.
here is my problem i have 2 -80 gig sata drives when i created my raid0 it
made it one 159 gig drive ,did this in the promise connectors aswell.should
it not be 1 striped 80 gig drive in windows.
in the raid utility it list them as 80 gig around.were am i going wrong i
was sure that i followed the manual .thanks
 
Andre said:
ok i found the drivers to do an install on sata 1 and sata2 ,i wantto run
them in raid 0 .
i set the bios as per the book and went in the utility and deleted old
volumes and created new ones as pre book.then poped in win xp home with sp2
and load driver for intel chip thru f6.got windows to format drives,loaded
win great.
here is my problem i have 2 -80 gig sata drives when i created my raid0 it
made it one 159 gig drive ,did this in the promise connectors aswell.should
it not be 1 striped 80 gig drive in windows.
Click to expand...

No, it should appear as 2 drives. You have 2 *drives*.

RAID 0 spans a *partition* across 2 drives.

So the drive letter that gets assigned to this partition should be ~160GB.
in the raid utility it list them as 80 gig around.were am i going wrong i
was sure that i followed the manual .thanks
Click to expand...

I don't see the problem.

If you wanted RAID 1 (mirrored) then you would have an 80GB partition.

Since you want RAID 0 (striped) you have a 160GB partition.

Ben
 
that must be it, i though in the book it said for stiping it it would show
as 1 -80 gig writing to both to be faster.but hey this not the first time i
am wrong nor the last thanks.
 
Andre LaFramboise said:
ok i found the drivers to do an install on sata 1 and sata2 ,i wantto run
them in raid 0 .> i set the bios as per the book and went in the utility
and deleted old volumes and created new ones as pre book.then poped in win
xp home with sp2 and load driver for intel chip thru f6.got windows to
format drives,loaded win great.
here is my problem i have 2 -80 gig sata drives when i created my raid0 it
made it one 159 gig drive ,did this in the promise connectors
aswell.should it not be 1 striped 80 gig drive in windows.
in the raid utility it list them as 80 gig around.were am i going wrong i
was sure that i followed the manual .thanks
Click to expand...

That's how RAID 0 striping works. It doubles the capacity of the hard
drives
and alternating data is written to both. RAID 1 mirroring keeps the size
the same since the second drive becomes a duplicate of the first.
 
Ben said:
No, it should appear as 2 drives. You have 2 *drives*.
Click to expand...

No. When striping (AKA "RAID 0") is done by a RAID controller
(instead of in software) it should appear to the OS as a single
physical drive. The RAID controller is the only thing that
deals with the individual drives: it hides the individual drives
from the OS and presents to the OS the illusion of a single large
drive.
RAID 0 spans a *partition* across 2 drives.
Click to expand...

No. Spanning a partition across multiple drives is quite
different from *striping* a partition across multiple drives.

When data is spanned across multiple drives, the "blocks" are
accessed /sequential/ order from the beginning of the drive 0 to
the end of the drive 0, then from the beginning of the drive 1 to
the end of the drive 1, and so on.

When data is striped across multiple drives, the "blocks" are
accessed in /alternating/ order. Block 0 is used on drive 0,
then drive 1, then drive 2 and so on; then block 1 is used on
all of the drives; then block 2 on all of the drives, ...
 
"Andre said:
ok i found the drivers to do an install on sata 1 and sata2 ,i wantto run
them in raid 0 .
i set the bios as per the book and went in the utility and deleted old
volumes and created new ones as pre book.then poped in win xp home with sp2
and load driver for intel chip thru f6.got windows to format drives,loaded
win great.
here is my problem i have 2 -80 gig sata drives when i created my raid0 it
made it one 159 gig drive ,did this in the promise connectors aswell.should
it not be 1 striped 80 gig drive in windows.
in the raid utility it list them as 80 gig around.were am i going wrong i
was sure that i followed the manual .thanks
Click to expand...

On a stripe, the controller can read a chunk (64KB in the example
below) from both IDE cables, at the same time. That offers the
possibility of doubling the data rate, and that is why the Stripe
column is labelled "Built for speed". The RAID mirror repeats the
identical data on both disks, and is intended to help if there is
a single drive failure. (Note - the final numbers at the bottom
of the columns are not exactly what you will see with your two
80GB drives - the numbers are fudged to illustrate a point.)

-------------------+------------------------+------------------------+
Non-RAID | Built for speed | Built for reliability |
-------------------+------------------------+------------------------+
Disk | Disk0 Disk1 | Disk0 Disk1 |
An ordinary 0KB | Raid0 0KB 64KB | Raid1 0KB 0KB |
single 64KB | Stripe 128KB 192KB | Mirror 64KB 64KB |
drive 128KB | 256KB 320KB | 128KB 128KB |
... | ... ... | ... ... |
80000KB | 159936KB 160000KB | 80000KB 80000KB |
----------------------------------------------------------------------

If using either RAID configuration, I heartily recommend the purchase
of a UPS power supply, to give your computer a reliable source of
AC power. A power interruption can do a lot more damage to a RAID,
than to an ordinary disk. I would sooner buy the UPS and install it,
than analyse all the ways the RAID can fail :-)

RAID arrays are also a pain in the a** to maintain. But you'll
learn all about that soon enough. Make sure you are doing
frequent backups!

If you "explore" your motherboard CD, there might be an Intel manual
on RAID hiding on there. There are also some manuals on the Intel
site, but they are harder to find. They explain some of this stuff.

This is Intel's latest manual. The manual is really intended for the
ICH6R, but it has some good advice on RAID0 and RAID1. The best
part is the troubleshooting section on PDF page 86. I don't know if
Intel's earlier manuals have quite as much information on what
to do when the array fails.

ftp://download.intel.com/support/chipsets/imst/sb/manual45_oem.pdf

Paul
 
The best thing to do with a raid array - before you use it in production -
is to simulate a drive failure and find out what happens, what to do to fix
it, and how long it takes to fix.

You should also benchmark to ensure you are getting the performance you
expect - naturally you should benchmark a single drive's performance 1st to
have something to compare to.

You will then understand why RAID 0 should only be used in rare
circumstances - where you can afford to lose all data.

If you aren't willing to do that, or don't see the value in all the above,
then you are running blind and will have to learn the hardway when a drive
fails.

Suffice it to say, RAID 1 is a pleasure.

NB: I have had a RAID 0 array running for about 7 years without fault on a
P2B-DS (dual P2 400) with a whopping read only DB that comes off DVD. For
all the power fails, it has never kicked up any fuss, but then it is a bunch
of read only files. This is a good use! Read only Databases.

If your data is valuable to warrant RAID 1 (isn't everyones?) the do get a
UPS.
 
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