RAID 0 and the formatting of Partitions - Crossposted

[Stephen]

Thank you for reading. I know this will seem fussy on my part but I like to
see what I can do here.

I've set up a RAID 0 with a pair of Maxtor SATA drives on an Intel P4 mobo.
It works very well. But some questions came to mind during the setup
process.

I had to establish the striped *before* installing the OS. This involved
going into the bios, selecting the drives for the stipe and interestingly
enough selecting the --size-- of the stripe i.e. one of 32, 64, or 128 kB!
This is before either partitioning or formatting! The process turned two
harddrives into one 'drive'.

So I choose 128 for performance then started the Windows install process.

Through the facilities Windows provides I was able to change the active
partition and get Windows onto something other than a 4KB cluster formated
NTFS partition. Windows got installed on an NTFS partition formatted with
32KB clusters on my 128 KB striped RAID 0 'drive'.

To be honest, I do not have a clue as to what is going on. Does each 32KB
cluster take up 128KB of harddrive space? Should I have arranged for the
NTFS partiton to be formatted with 128KB clusters [ the Disk Management
option however only allows up to 64KB].

How are the 32KB clusters 'split' across the RAID 0 stripe?

Maybe I should have chosen a 64KB RAID 0 stripe then formatted NTFS with
64KB clusters?

BTW because the RAID 0 was set up *before* Windows was installed I didb't
have to upgrade the disks to dynamic.

Any insights welcome - and thanks.

Stephen

 

[Juhan Leemet]

Thank you for reading. I know this will seem fussy on my part but I like to
see what I can do here.

I've set up a RAID 0 with a pair of Maxtor SATA drives on an Intel P4 mobo.
It works very well. But some questions came to mind during the setup
process.

I had to establish the striped *before* installing the OS. This involved
going into the bios, selecting the drives for the stipe and interestingly
enough selecting the --size-- of the stripe i.e. one of 32, 64, or 128 kB!
This is before either partitioning or formatting! The process turned two
harddrives into one 'drive'.

So I choose 128 for performance then started the Windows install process.

Based on what? This means (to me) that you will not see any read
performance improvements for small files, since they will be coming
entirely from one of your disks. Bigger is not necessarily better, in this
case, but it all depends on what you do.

Through the facilities Windows provides I was able to change the active
partition and get Windows onto something other than a 4KB cluster formated
NTFS partition. Windows got installed on an NTFS partition formatted with
32KB clusters on my 128 KB striped RAID 0 'drive'.

To be honest, I do not have a clue as to what is going on. Does each 32KB
cluster take up 128KB of harddrive space? Should I have arranged for the
NTFS partiton to be formatted with 128KB clusters [ the Disk Management
option however only allows up to 64KB].

No they are independent.

If you have no clue, then why are you even screwing around with RAID0?
Looking for trouble? You can definitely find it. For example, did you
realize that you just doubled the probability that you will lose all of
your disk files? If one disk fails, you lose it all! Make sure you are
backing up your good stuff regularly. You don't want an "oh, no!" moment.

How are the 32KB clusters 'split' across the RAID 0 stripe?

They are laid down sequentially. The first 4 32KB clusters are on the 1st
disk (1st 128KB). Then the second 4 32KB clusters are on the 2nd disk.
Then back to the 1st disk (2nd 128KB), etc.

Maybe I should have chosen a 64KB RAID 0 stripe then formatted NTFS with
64KB clusters?

The strips and cluster size are really independent. I don't have enough
experience with NTFS to know whether they benefit from being identical.
Others may tell us. I have not seen any notes to that effect.

Who knows? It really depends on how your system will be used. These are
tuning parameters. The usual way to tune a system is to find some tests
(aka benchmarks) that are similar to your intended operation. Then you can
measure the performance of your setup as you change the parameters and
pick the best combination for you. Note that this is extremely time
consuming. You have to configure with a set of parameters, install
software, run tests, record values. Repeat for every combination of
parameters that you want to consider. Then look at the recorded values and
pick the "best" (different for different people/uses) one (for you).

The other way to go is to Google around and find someone else who has
already done this kind of tuning on their system, verify that they use
their system in a similar way to your usage. Use their parameters.

As an example, a machine that is a news bulletin server (many, many tiny
files) would be tuned differently from one that is an apache web server
serving up large .pdf files. YMMV

 

[Guest]

Windows XP default is 4KB cluster size-Std NTFS size , changing to 32KB size
is like going backwards to Fat 32, establishing the raid array is standard,
before loading the operating system, I'm surprised you chose SATA,,Tests on
many premier web sites, show SATA is slower than 7200RPM-ATA-5 with 8MB
caches( Look for SATA v ATA on WWW), due to pci 2.2 specifications (33MHZ
bandwidth buses or 133MB/s speed maximum), a lot of people have been
"clipped" chasing the speed angle, One site tested SATA v ATA-5 and concluded
WinXP does not support the bandwidth of 150mb/s, which makes a lot of sense ,
as WinXP was released before
SATA showed up on the market, Microsoft has said "Ataport", the new mini
drivers,
will support SATA nad ATA's , however this will be in "Future" operating
systems.
SATA attempts to send a lot of data ect," down very few lines", this quite
different than normal to date, as transfer wires have incresed speed has
increased.
40 wire+shielded 66MB/s, 100MB/s, 133MB/s speeds
68 wire+ shielded SCSI 160mb/s
80 wire + shielded SCSI 320mb/s
You understand ? Increase in transfer wires increase in speeds to from
disk drives to memory, Now here comes SATA and transfer wires reduced to "7"
or so and it goes 150MB/s, The new technology of SATA is a " faster clock
chip", the compression on transfer data has sky rocketed, this slows things
down, Plus WINXP has SCSI port drivers and ATA port drivers, NO SATA port
drivers, Since Longhorn is a MS future operating system, ATAport may be in
there, MS has not said yet it included in Longhorn, SATA will work with WINXP
its still second class, The golden rule- If the operating system does not
have initial support for Hardware, its like throwing dice "snake eyes" you
lose, the operating system must be able to handle the hardware in its coding,
RAID and its not working in many operating systems, till coding schemes were
included is the " Number 1 example ". I'll wait until MS includes SATA
drivers in the furture operting systems, this way "WHCL has optimized" the
driver for the particular operating system of MS, SATA has no WHCL
driver optimization.
Rho1raid(VIP) not MVP

Thank you for reading. I know this will seem fussy on my part but I like to
see what I can do here.

I've set up a RAID 0 with a pair of Maxtor SATA drives on an Intel P4 mobo.
It works very well. But some questions came to mind during the setup
process.

I had to establish the striped *before* installing the OS. This involved
going into the bios, selecting the drives for the stipe and interestingly
enough selecting the --size-- of the stripe i.e. one of 32, 64, or 128 kB!
This is before either partitioning or formatting! The process turned two
harddrives into one 'drive'.

So I choose 128 for performance then started the Windows install process.

Through the facilities Windows provides I was able to change the active
partition and get Windows onto something other than a 4KB cluster formated
NTFS partition. Windows got installed on an NTFS partition formatted with
32KB clusters on my 128 KB striped RAID 0 'drive'.

To be honest, I do not have a clue as to what is going on. Does each 32KB
cluster take up 128KB of harddrive space? Should I have arranged for the
NTFS partiton to be formatted with 128KB clusters [ the Disk Management
option however only allows up to 64KB].

How are the 32KB clusters 'split' across the RAID 0 stripe?

Maybe I should have chosen a 64KB RAID 0 stripe then formatted NTFS with
64KB clusters?

BTW because the RAID 0 was set up *before* Windows was installed I didb't
have to upgrade the disks to dynamic.

Any insights welcome - and thanks.

Stephen

 

[Guest]

WHQL-windows hardware quality labs has not tested and optimzed SATA drivers,
plus ATA and SCSI was optimized in all components as they were around.

Windows XP default is 4KB cluster size-Std NTFS size , changing to 32KB size
is like going backwards to Fat 32, establishing the raid array is standard,
before loading the operating system, I'm surprised you chose SATA,,Tests on
many premier web sites, show SATA is slower than 7200RPM-ATA-5 with 8MB
caches( Look for SATA v ATA on WWW), due to pci 2.2 specifications (33MHZ
bandwidth buses or 133MB/s speed maximum), a lot of people have been
"clipped" chasing the speed angle, One site tested SATA v ATA-5 and concluded
WinXP does not support the bandwidth of 150mb/s, which makes a lot of sense ,
as WinXP was released before
SATA showed up on the market, Microsoft has said "Ataport", the new mini
drivers,
will support SATA nad ATA's , however this will be in "Future" operating
systems.
SATA attempts to send a lot of data ect," down very few lines", this quite
different than normal to date, as transfer wires have incresed speed has
increased.
40 wire+shielded 66MB/s, 100MB/s, 133MB/s speeds
68 wire+ shielded SCSI 160mb/s
80 wire + shielded SCSI 320mb/s
You understand ? Increase in transfer wires increase in speeds to from
disk drives to memory, Now here comes SATA and transfer wires reduced to "7"
or so and it goes 150MB/s, The new technology of SATA is a " faster clock
chip", the compression on transfer data has sky rocketed, this slows things
down, Plus WINXP has SCSI port drivers and ATA port drivers, NO SATA port
drivers, Since Longhorn is a MS future operating system, ATAport may be in
there, MS has not said yet it included in Longhorn, SATA will work with WINXP
its still second class, The golden rule- If the operating system does not
have initial support for Hardware, its like throwing dice "snake eyes" you
lose, the operating system must be able to handle the hardware in its coding,
RAID and its not working in many operating systems, till coding schemes were
included is the " Number 1 example ". I'll wait until MS includes SATA
drivers in the furture operting systems, this way "WHCL has optimized" the
driver for the particular operating system of MS, SATA has no WHCL
driver optimization.
Rho1raid(VIP) not MVP

Thank you for reading. I know this will seem fussy on my part but I like to
see what I can do here.

I've set up a RAID 0 with a pair of Maxtor SATA drives on an Intel P4 mobo.
It works very well. But some questions came to mind during the setup
process.

I had to establish the striped *before* installing the OS. This involved
going into the bios, selecting the drives for the stipe and interestingly
enough selecting the --size-- of the stripe i.e. one of 32, 64, or 128 kB!
This is before either partitioning or formatting! The process turned two
harddrives into one 'drive'.

So I choose 128 for performance then started the Windows install process.

Through the facilities Windows provides I was able to change the active
partition and get Windows onto something other than a 4KB cluster formated
NTFS partition. Windows got installed on an NTFS partition formatted with
32KB clusters on my 128 KB striped RAID 0 'drive'.

To be honest, I do not have a clue as to what is going on. Does each 32KB
cluster take up 128KB of harddrive space? Should I have arranged for the
NTFS partiton to be formatted with 128KB clusters [ the Disk Management
option however only allows up to 64KB].

How are the 32KB clusters 'split' across the RAID 0 stripe?

Maybe I should have chosen a 64KB RAID 0 stripe then formatted NTFS with
64KB clusters?

BTW because the RAID 0 was set up *before* Windows was installed I didb't
have to upgrade the disks to dynamic.

Any insights welcome - and thanks.

Stephen

 

[Stephen]

| On Mon, 20 Sep 2004 13:59:50 +0000, Stephen wrote:
| > <clip>
|
| --
| Juhan Leemet
| Logicognosis, Inc.
|

Thanks, yes I do back up my 'data' so I'm not worried *too* much. It's just
that I decided I want to learn about this a bit. I figured the way to do it
is to dive right in and have some fun.

Stephen

 

[Stephen]

| WHQL-windows hardware quality labs has not tested and optimzed SATA
drivers,
| plus ATA and SCSI was optimized in all components as they were around.
|
| "<clip>

The SATA drives work very well and the performance, at least on the 'user'
level is good. I read that performance can be increased on a 'basic' ATA
drive by formatting larger clusters, although there's decrease in storage
space efficiency.

Stephen

 

[Ron Reaugh]

process.

Based on what? This means (to me) that you will not see any read
performance improvements for small files, since they will be coming
entirely from one of your disks. Bigger is not necessarily better, in this
case, but it all depends on what you do.

Yes, I'd have chosen 32K but there is an IF.

The classic definition of stripe size is the element that spans the stripe
set before starting over at the first drive again. If the size he set in
initially is classic and two drives then there is 64K per drive. You have
to read each RAID manual carefully as often they hide that or don't include
that and SOMETIMES even their TS doesn't know. I've been waiting for over 4
years for Promise to answer how they define stripe size. So I'd chose 32K
'stripe units' per drive.

 

[Ron Reaugh]

Windows XP default is 4KB cluster size-Std NTFS size , changing to 32KB size
is like going backwards to Fat 32, establishing the raid array is standard,
before loading the operating system, I'm surprised you chose SATA,,Tests on
many premier web sites, show SATA is slower than 7200RPM-ATA-5 with 8MB

Nope, have a look at the figures for the SATA WDC Raptor.

caches( Look for SATA v ATA on WWW), due to pci 2.2 specifications (33MHZ
bandwidth buses or 133MB/s speed maximum), a lot of people have been
"clipped" chasing the speed angle, One site tested SATA v ATA-5 and concluded
WinXP does not support the bandwidth of 150mb/s, which makes a lot of

sense ,

HUH, an OS doesn't know about hardware bandwidths.

as WinXP was released before
SATA showed up on the market, Microsoft has said "Ataport", the new mini
drivers,
will support SATA nad ATA's , however this will be in "Future" operating
systems.
SATA attempts to send a lot of data ect," down very few lines", this quite
different than normal to date, as transfer wires have incresed speed has
increased.
40 wire+shielded 66MB/s, 100MB/s, 133MB/s speeds
68 wire+ shielded SCSI 160mb/s
80 wire + shielded SCSI 320mb/s
You understand ? Increase in transfer wires increase in speeds to from
disk drives to memory, Now here comes SATA and transfer wires reduced to "7"
or so and it goes 150MB/s, The new technology of SATA is a " faster clock
chip", the compression on transfer data has sky rocketed, this slows things
down,

Just NO!

Plus WINXP has SCSI port drivers and ATA port drivers, NO SATA port
drivers,
HUH?

Since Longhorn is a MS future operating system, ATAport may be in
there, MS has not said yet it included in Longhorn, SATA will work with WINXP
its still second class,
Nonsense.

The golden rule- If the operating system does not
have initial support for Hardware, its like throwing dice "snake eyes" you
lose, the operating system must be able to handle the hardware in its coding,
RAID and its not working in many operating systems, till coding schemes were
included is the " Number 1 example ". I'll wait until MS includes SATA
drivers in the furture operting systems, this way "WHCL has optimized" the
driver for the particular operating system of MS, SATA has no WHCL
driver optimization.

Where did you make up all this trash from?

 

[Ron Reaugh]

WHQL-windows hardware quality labs has not tested and optimzed SATA drivers,
plus ATA and SCSI was optimized in all components as they were around.

All that means absolutely NOTHING!

Windows XP default is 4KB cluster size-Std NTFS size , changing to 32KB size
is like going backwards to Fat 32, establishing the raid array is standard,
before loading the operating system, I'm surprised you chose SATA,,Tests on
many premier web sites, show SATA is slower than 7200RPM-ATA-5 with 8MB
caches( Look for SATA v ATA on WWW), due to pci 2.2 specifications (33MHZ
bandwidth buses or 133MB/s speed maximum), a lot of people have been
"clipped" chasing the speed angle, One site tested SATA v ATA-5 and concluded
WinXP does not support the bandwidth of 150mb/s, which makes a lot of sense ,
as WinXP was released before
SATA showed up on the market, Microsoft has said "Ataport", the new mini
drivers,
will support SATA nad ATA's , however this will be in "Future" operating
systems.
SATA attempts to send a lot of data ect," down very few lines", this quite
different than normal to date, as transfer wires have incresed speed has
increased.
40 wire+shielded 66MB/s, 100MB/s, 133MB/s speeds
68 wire+ shielded SCSI 160mb/s
80 wire + shielded SCSI 320mb/s
You understand ? Increase in transfer wires increase in speeds to from
disk drives to memory, Now here comes SATA and transfer wires reduced to "7"
or so and it goes 150MB/s, The new technology of SATA is a " faster clock
chip", the compression on transfer data has sky rocketed, this slows things
down, Plus WINXP has SCSI port drivers and ATA port drivers, NO SATA port
drivers, Since Longhorn is a MS future operating system, ATAport may be in
there, MS has not said yet it included in Longhorn, SATA will work with WINXP
its still second class, The golden rule- If the operating system does not
have initial support for Hardware, its like throwing dice "snake eyes" you
lose, the operating system must be able to handle the hardware in its coding,
RAID and its not working in many operating systems, till coding schemes were
included is the " Number 1 example ". I'll wait until MS includes SATA
drivers in the furture operting systems, this way "WHCL has optimized" the
driver for the particular operating system of MS, SATA has no WHCL
driver optimization.
Rho1raid(VIP) not MVP

Thank you for reading. I know this will seem fussy on my part but I like to
see what I can do here.

I've set up a RAID 0 with a pair of Maxtor SATA drives on an Intel P4 mobo.
It works very well. But some questions came to mind during the setup
process.

I had to establish the striped *before* installing the OS. This involved
going into the bios, selecting the drives for the stipe and interestingly
enough selecting the --size-- of the stripe i.e. one of 32, 64, or 128 kB!
This is before either partitioning or formatting! The process turned two
harddrives into one 'drive'.

So I choose 128 for performance then started the Windows install process.

Through the facilities Windows provides I was able to change the active
partition and get Windows onto something other than a 4KB cluster formated
NTFS partition. Windows got installed on an NTFS partition formatted with
32KB clusters on my 128 KB striped RAID 0 'drive'.

To be honest, I do not have a clue as to what is going on. Does each 32KB
cluster take up 128KB of harddrive space? Should I have arranged for the
NTFS partiton to be formatted with 128KB clusters [ the Disk Management
option however only allows up to 64KB].

How are the 32KB clusters 'split' across the RAID 0 stripe?

Maybe I should have chosen a 64KB RAID 0 stripe then formatted NTFS with
64KB clusters?

BTW because the RAID 0 was set up *before* Windows was installed I didb't
have to upgrade the disks to dynamic.

Any insights welcome - and thanks.

Stephen

 

[Ron Reaugh]

BTW because the RAID 0 was set up *before* Windows was installed I didb't
have to upgrade the disks to dynamic.

That's expected as the dynamic part arises for the OS's intrinsic SW RAID
functionality and not 3rd party add-on cards.

 

[Juhan Leemet]

| On Mon, 20 Sep 2004 13:59:50 +0000, Stephen wrote:
| > <clip>
|
| --
| Juhan Leemet
| Logicognosis, Inc.
|

Thanks, yes I do back up my 'data' so I'm not worried *too* much. It's just
that I decided I want to learn about this a bit. I figured the way to do it
is to dive right in and have some fun.

OK, that is the right attitude. I also like to learn about things by
doing. That is how you really "fix" (as in photographic development) your
"book learning". Didn't mean to be harsh or discouraging. Good luck!