RAID 1 (mirroring) Excruciatingly Slow

[tomatohead]

I just copied a 3 GB file on a RAID 1 system, from one folder to
another.
I found it was excruciatingly slow. I mean ... it was virtually
unusably slow.
It was so slow in fact, that I can't imagine this is the normal
performance level for such a system.

The computer in question is a 2.0 GHz P4 with 2 Maxtor SATA drives.
I've tried the "Legacy (SATA Only) mode" in the BIOS as well as the
"Auto" mode.
If I'm not mistaken the properties sheet claims they are using DMA 5
mode.

The CPU completely tops out during the copy and system is unresponsive
for the entire course of the copy. To give you a rough idea, it took
somewhere in the neighborhood of 35 minutes to copy a 3 GB file.

So, my question is this: Is my intuition right, and something else is
going on ?
Or is this really within the expected performance range of a system
like this ?

Thanks
E

 

[DL]

Software raid utilises the cpu hardware raid does not, so I guess with heavy
usage theres bound to be a performance hit.

 

[tomatohead]

Software raid utilises the cpu hardware raid does not, so I guess with heavy
usage theres bound to be a performance hit.

Yeah, I knew there was going to be a performance hit ... I just had no
idea it was going to be this drammatic.

I have done some simple timing tests ... and with the RAID mirror
established hard drive write operations are roughly 10-15 times
slower. I mean, that is quite a hit !

Honestly, I don't even consider this within the realm of useability
.... and this is with a 2.0 GHz.

It is so bad I thought maybe something else might be going on.

 

[tomatohead]

Software raid utilises the cpu hardware raid does not, so I guess with heavy
usage theres bound to be a performance hit.

Actually ... I just set up another system and tested software RAID 1
on it.
This is an IDE system running w2000 server ... and it's performance
was far better. With RAID running it was ~ twice as slow, while the
other system (with a far faster CPU, and SATA drives) was 12 times as
slow with RAID.

So something is definetely going on.

Some things that are different between the systems:
slow system - w2003 server, SATA, 120 GB hard drives.
fast system - w2000 server, IDE, 10 GB hard drives.

Something must be going on with the SATA. I can't imagine the larger
hard drives would cause such a noticable difference.

 

[DL]

Afraid I use hardware raid, mirror, with 160gb sata. I suffer no performance
issues