Very slow SATA RAID under XP

[Guest Peter]

Just rebuilt my PC with a SATA RAID hard drive array (mirror) using a

Siig SATA-300 controller, and win XP. Last one was win2000, single

SATA drive but used to be a RAID mirror too.

 

All works fine but there is massive disk activity running certain apps

which write a lot of small files. The activity takes a very long time,

about 10-100x longer than it should, or used to under win2000. In

particular, the exit newsgroup purging which Agent newsreader does is

extremely slow.

 

Big file reads and writes (say 50MB) are quick.

 

Has anyone come across this under XP, or with certain SATA

controllers?

 

I have contacted Siig but they don't support their products.

 

My experience of these controllers is that they speed up HD ops

massively, whether SCSI or SATA (both of which I have used extensively

under NT4 and win2000).

[Guest Shenan Stanley]

Re: Very slow SATA RAID under XP

 

Peter wrote:

> Just rebuilt my PC with a SATA RAID hard drive array (mirror) using

> a Siig SATA-300 controller, and win XP. Last one was win2000, single

> SATA drive but used to be a RAID mirror too.

>

> All works fine but there is massive disk activity running certain

> apps which write a lot of small files. The activity takes a very

> long time, about 10-100x longer than it should, or used to under

> win2000. In particular, the exit newsgroup purging which Agent

> newsreader does is extremely slow.

>

> Big file reads and writes (say 50MB) are quick.

>

> Has anyone come across this under XP, or with certain SATA

> controllers?

>

> I have contacted Siig but they don't support their products.

>

> My experience of these controllers is that they speed up HD ops

> massively, whether SCSI or SATA (both of which I have used

> extensively under NT4 and win2000).

 

 

Mirror RAID does not improve performance.

 

--

Shenan Stanley

MS-MVP

--

How To Ask Questions The Smart Way

http://www.catb.org/~esr/faqs/smart-questions.html

[Guest nospam@nospam.com]

Re: Very slow SATA RAID under XP

 

My experience with SIIG products hasn't been very positive. Try

another brand of SATA controller.

 

GS

[Guest Peter]

Re: Very slow SATA RAID under XP

 

 

"Shenan Stanley" <newshelper@gmail.com> wrote

>Peter wrote:

>> Just rebuilt my PC with a SATA RAID hard drive array (mirror) using

>> a Siig SATA-300 controller, and win XP. Last one was win2000, single

>> SATA drive but used to be a RAID mirror too.

>>

>> All works fine but there is massive disk activity running certain

>> apps which write a lot of small files. The activity takes a very

>> long time, about 10-100x longer than it should, or used to under

>> win2000. In particular, the exit newsgroup purging which Agent

>> newsreader does is extremely slow.

>>

>> Big file reads and writes (say 50MB) are quick.

>>

>> Has anyone come across this under XP, or with certain SATA

>> controllers?

>>

>> I have contacted Siig but they don't support their products.

>>

>> My experience of these controllers is that they speed up HD ops

>> massively, whether SCSI or SATA (both of which I have used

>> extensively under NT4 and win2000).

>

>

>Mirror RAID does not improve performance.

 

Of course not. But here we are looking at a 100x slowdown.

[Guest Peter]

Re: Very slow SATA RAID under XP

 

 

nospam@nospam.com wrote

>My experience with SIIG products hasn't been very positive. Try

>another brand of SATA controller.

 

I might do, but will the PC still boot?

 

I have found that the format of a HD which was in a mirror raid array

is not the same as the format of a HD which was used alone. Why this

is, I haven't got a clue since it isn't necessary AFAICS. The PC does

not even boot from a HD which was in an array and is then moved to the

standalone config on the *same* controller. So if I change the

controller to another brand, I might lose all the data...

 

SIIG just use the Silicon Image SIL3132 Softraid 5 chipset which lots

of firms use. The SIL31xx chipset is all over the various motherboards

from Gigabyte, ASUS, etc. In this case I am using a standalone RAID

controller (2x SATA 300, PCI-Ex bus) and even I bought a spare one, to

avoid this kind of dependency. My motherboard happens to have a SATA

RAID controller already and probably with the same chipset, but I

didn't use it for this reason.

 

On another machine (critical one, used for accounting) I used an

Adaptec SATA RAID (150) controller and that one works fine, but in

this case I wanted a 300 one and Adaptec don't seem to make those.

[Guest Peter]

Re: Very slow SATA RAID under XP

 

FYI the chipset is

 

http://www.siimage.com/products/product.aspx?id=32

 

and the controller is

 

http://www.siig.com/ViewProduct.aspx?pn=SC-SAER12-S2

 

Interestingly, their windows management utility does not install. When

I start it, Winzip appears instead!!

[Guest Anteaus]

Re: Very slow SATA RAID under XP

 

 

Mirrors take several hours to initialise and during this time they may be

slow. Leave on overnight and see if things have improved.

 

Other thing, check in Device Manager to see if the disk driver is using DMA.

If not, disk access will be very slow, and will cause 100% CPU load whenever

the disk is accessed.

[Guest Peter]

Re: Very slow SATA RAID under XP

 

 

Anteaus <Anteaus@discussions.microsoft.com> wrote:

>

>Mirrors take several hours to initialise and during this time they may be

>slow. Leave on overnight and see if things have improved.

 

It's been a week now - otherwise yes I agree.

>Other thing, check in Device Manager to see if the disk driver is using DMA.

>If not, disk access will be very slow, and will cause 100% CPU load whenever

>the disk is accessed.

 

There is nothing abnormal showing, and a look at Perf Monitor shows

CPU activity running around the 2-3% mark, during the very intensive

disk activity.

 

It is as if write cacheing was disabled, but it is checked as enabled

(though the option is greyed-out).

 

One other difference between this and previous installations is that

this HD is NTFS whereas previous ones were FAT32. I did find, years

ago, that NTFS was far slower when it came to accessing large numbers

of small files. But I don't think it is the problem here.

 

x----------x

[Guest HeyBub]

Re: Very slow SATA RAID under XP

 

Shenan Stanley wrote:

>

>

> Mirror RAID does not improve performance.

>

 

Yes it can. On some controllers. There's obviously no improvement when

writing a file, but when reading, the closest head to the requested track

gets the call.

 

If one head is on track 10 the other head on track 90 and the requested data

is on track 90, then head 2 will be assigned the read, eliminating the

access time necessary to move head 1.