Hi

In an article about the performance of sata raid controllers (
StorageReview:
http://www.storagereview.com/article...tml?page=0%2C5
) using NCQ or TCQ. it stated that TCQ is much faster than NCQ:

"SATA TCQ and SATA RAID have the potential to deliver benefits to the
server market just as great as those of SCSI TCQ and SCSI RAID."

So by using a SATA-1 TCQ RAID controller and WD Raptor disks one can get
close to SCSI performance. (Sata 2 does not actually give the same
performance according other tests I have read.)

The article was written in 2004, and in four years much may have
happened with NCQ. So the question is, does anybody know if much has
happened with NCQ? or can I still trust the articles conclusions in
terms of its performance?

regards

tom

TCQ was a disaster, it was built on top of a flawed attemp to make PATA multitask.
I doubt anyone supports TCQ today, especially on SATA. Microsoft and Intel do NOT.

NCQ performance varies from negative to positive compared to original IDE.
You have to find some recent benchmarks, including both controllers and drives.

"Tom Forsmo" <spam@nospam.net> wrote in message news:481f1b24$1@news.broadpark.no...
> Hi
>
> In an article about the performance of sata raid controllers (
> StorageReview:
> http://www.storagereview.com/article...tml?page=0%2C5
> ) using NCQ or TCQ. it stated that TCQ is much faster than NCQ:
>
> "SATA TCQ and SATA RAID have the potential to deliver benefits to the
> server market just as great as those of SCSI TCQ and SCSI RAID."
>
> So by using a SATA-1 TCQ RAID controller and WD Raptor disks one can get
> close to SCSI performance. (Sata 2 does not actually give the same
> performance according other tests I have read.)
>
> The article was written in 2004, and in four years much may have
> happened with NCQ. So the question is, does anybody know if much has
> happened with NCQ? or can I still trust the articles conclusions in
> terms of its performance?
>

Eric Gisin wrote:
> TCQ was a disaster, it was built on top of a flawed attemp to make PATA
> multitask.
> I doubt anyone supports TCQ today, especially on SATA. Microsoft and
> Intel do NOT.

Then I think you have been misinformed, some SATA disk support TCQ
exceptionally well, such as the WD Raptor disks. Paired with a TCQ sata
controller they outperform any NCQ disks on market. It actually comes
close to SCSI performance, which no NCQ disks is able of achieving. Mind
you this is with server type load. With single user load, the
performance is somewhat lower than with NCQ. The reason for that is
because TCQ is a more heavyweight protocol than NCQ, so you wont see a
gain until the load is increased somewhat.

You should read the entire article, it is quite interresting
StorageReview:
http://www.storagereview.com/article...tml?page=0%2C5

> NCQ performance varies from negative to positive compared to original IDE.
> You have to find some recent benchmarks, including both controllers and
> drives.

I have been looking around, and havent found much, neither benchmarks
nor info about NCQ updates.

regards

tom

Eric Gisin wrote:
> TCQ was a disaster, it was built on top of a flawed attemp to make PATA
> multitask.
> I doubt anyone supports TCQ today, especially on SATA. Microsoft and
> Intel do NOT.

Then I think you have been misinformed, some SATA disk support TCQ
exceptionally well, such as the WD Raptor disks. Paired with a TCQ sata
controller they outperform any NCQ disks on market. It actually comes
close to SCSI performance, which no NCQ disks is able of achieving. Mind
you this is with server type load. With single user load, the
performance is somewhat lower than with NCQ. The reason for that is
because TCQ is a more heavyweight protocol than NCQ, so you wont see a
gain until the load is increased somewhat.

You should read the entire article, it is quite interresting
StorageReview:
http://www.storagereview.com/article...tml?page=0%2C5

> NCQ performance varies from negative to positive compared to original IDE.
> You have to find some recent benchmarks, including both controllers and
> drives.

I have been looking around, and havent found much, neither benchmarks
nor info about NCQ updates.

regards

tom

In comp.sys.ibm.pc.hardware.storage Tom Forsmo <spam@nospam.net> wrote:
> Hi

> In an article about the performance of sata raid controllers (
> StorageReview:
> http://www.storagereview.com/article...tml?page=0%2C5
> ) using NCQ or TCQ. it stated that TCQ is much faster than NCQ:

> "SATA TCQ and SATA RAID have the potential to deliver benefits to the
> server market just as great as those of SCSI TCQ and SCSI RAID."

> So by using a SATA-1 TCQ RAID controller and WD Raptor disks one can get
> close to SCSI performance. (Sata 2 does not actually give the same
> performance according other tests I have read.)

WD makes this claim for some time now, because they do not have
SCSI disks. I think it is a marketing-lie.

> The article was written in 2004, and in four years much may have
> happened with NCQ. So the question is, does anybody know if much has
> happened with NCQ? or can I still trust the articles conclusions in
> terms of its performance?

I think you copuld not trust it 2004 and you cannot trust it now.

Arno

In comp.sys.ibm.pc.hardware.storage Tom Forsmo <spam@nospam.net> wrote:
> Hi

> In an article about the performance of sata raid controllers (
> StorageReview:
> http://www.storagereview.com/article...tml?page=0%2C5
> ) using NCQ or TCQ. it stated that TCQ is much faster than NCQ:

> "SATA TCQ and SATA RAID have the potential to deliver benefits to the
> server market just as great as those of SCSI TCQ and SCSI RAID."

> So by using a SATA-1 TCQ RAID controller and WD Raptor disks one can get
> close to SCSI performance. (Sata 2 does not actually give the same
> performance according other tests I have read.)

WD makes this claim for some time now, because they do not have
SCSI disks. I think it is a marketing-lie.

> The article was written in 2004, and in four years much may have
> happened with NCQ. So the question is, does anybody know if much has
> happened with NCQ? or can I still trust the articles conclusions in
> terms of its performance?

I think you copuld not trust it 2004 and you cannot trust it now.

Arno

Arno Wagner wrote:

> WD makes this claim for some time now, because they do not have
> SCSI disks. I think it is a marketing-lie.

If you had read the article I references, you would see they have made
measurements comparing the Raptor disk to both SCSI, SATA NCQ and SATA
non-NCQ. And the Raptor is by far the fastest disk of the SATA types,
for server type load. The results have been feed into a long standing
peformance table where you can compare different types of disks, both
SCSI and SATA types, if you sort it by performance, you will see SCSI
holding the top positions, the highest performant sata disk mentioned on
the list is the Raptor. After that you find the all the other SATAs.

But my question is, has anything changed with NCQ. But after having
studied it, I dont think any changes have occured. The NCQ
implementation is really only an implementation of the TCQ simple mode.
Simple mode alone gives some performance boost. The referenced article
shows that NCQ disk is more suited for desktop load, while TCQ is more
suited for server load. And that is why I suspect NCQ has not changed much.


regards

thomas

Arno Wagner wrote:

> WD makes this claim for some time now, because they do not have
> SCSI disks. I think it is a marketing-lie.

If you had read the article I references, you would see they have made
measurements comparing the Raptor disk to both SCSI, SATA NCQ and SATA
non-NCQ. And the Raptor is by far the fastest disk of the SATA types,
for server type load. The results have been feed into a long standing
peformance table where you can compare different types of disks, both
SCSI and SATA types, if you sort it by performance, you will see SCSI
holding the top positions, the highest performant sata disk mentioned on
the list is the Raptor. After that you find the all the other SATAs.

But my question is, has anything changed with NCQ. But after having
studied it, I dont think any changes have occured. The NCQ
implementation is really only an implementation of the TCQ simple mode.
Simple mode alone gives some performance boost. The referenced article
shows that NCQ disk is more suited for desktop load, while TCQ is more
suited for server load. And that is why I suspect NCQ has not changed much.


regards

thomas

In comp.sys.ibm.pc.hardware.storage Tom Forsmo <spam@nospam.net> wrote:

> Arno Wagner wrote:

>> WD makes this claim for some time now, because they do not have
>> SCSI disks. I think it is a marketing-lie.

> If you had read the article I references, you would see they have made
> measurements comparing the Raptor disk to both SCSI, SATA NCQ and SATA
> non-NCQ. And the Raptor is by far the fastest disk of the SATA types,
> for server type load. The results have been feed into a long standing
> peformance table where you can compare different types of disks, both
> SCSI and SATA types, if you sort it by performance, you will see SCSI
> holding the top positions, the highest performant sata disk mentioned on
> the list is the Raptor. After that you find the all the other SATAs.

I did not calim that the Raptor was slow. What WD has claimed, however,
time and again, is that the Raptor is just as good as an SCSI disk.
It is not. It is, of course, faster than slower spinning (S)ATA
drives, unless you are interessted primarily in linear performance.

> But my question is, has anything changed with NCQ. But after having
> studied it, I dont think any changes have occured.

I agree.

> The NCQ implementation is really only an implementation of the TCQ
> simple mode. Simple mode alone gives some performance boost. The
> referenced article shows that NCQ disk is more suited for desktop
> load, while TCQ is more suited for server load. And that is why I
> suspect NCQ has not changed much.

It is also that on high-performance set-ups, the command reordering,
buffering, etc. is done by the OS anyways. In extreme cases (e.g.
an Oracle server) it is even done by the application. The disk can
add a little, but not that much.

Arno

In comp.sys.ibm.pc.hardware.storage Tom Forsmo <spam@nospam.net> wrote:

> Arno Wagner wrote:

>> WD makes this claim for some time now, because they do not have
>> SCSI disks. I think it is a marketing-lie.

> If you had read the article I references, you would see they have made
> measurements comparing the Raptor disk to both SCSI, SATA NCQ and SATA
> non-NCQ. And the Raptor is by far the fastest disk of the SATA types,
> for server type load. The results have been feed into a long standing
> peformance table where you can compare different types of disks, both
> SCSI and SATA types, if you sort it by performance, you will see SCSI
> holding the top positions, the highest performant sata disk mentioned on
> the list is the Raptor. After that you find the all the other SATAs.

I did not calim that the Raptor was slow. What WD has claimed, however,
time and again, is that the Raptor is just as good as an SCSI disk.
It is not. It is, of course, faster than slower spinning (S)ATA
drives, unless you are interessted primarily in linear performance.

> But my question is, has anything changed with NCQ. But after having
> studied it, I dont think any changes have occured.

I agree.

> The NCQ implementation is really only an implementation of the TCQ
> simple mode. Simple mode alone gives some performance boost. The
> referenced article shows that NCQ disk is more suited for desktop
> load, while TCQ is more suited for server load. And that is why I
> suspect NCQ has not changed much.

It is also that on high-performance set-ups, the command reordering,
buffering, etc. is done by the OS anyways. In extreme cases (e.g.
an Oracle server) it is even done by the application. The disk can
add a little, but not that much.

Arno