87MB/s sounds a lot better than the 2MB/s you originally reported.

 

You can bet that these exact same issues occur in many PCs, but most people never notice the difference when loading small documents and programs.  Glad you finally figured it out.

Sorry, but what is the "round robin"? Cheers.

 

Sorry, but what is the "round robin"? Cheers.

 

 

Staggering the disks to different controllers to keep from oversaturating the weakest link.

 

For example, 4 on the onboard, 3 on one of the PCI-X controllers, and 3 on the other. I did something like that when I had 10 disks.

Oh yeah, you would want to definitely place the fastest drives on the onboard mobo interface ports, followed by any of your fastest add-on cards for your other fastest to slower drives.

I'm glad you are working at a great speed again even though I'm a lttle surprized it made such a difference. Maybe bus contention?

 

Peter

 

I'm in the process of adding a new parity drive.  I ran preclear on the new drive and then decided to do a last parity check before switching out the old parity for the new one.  My old parity checks would run at 90MB/s.  This one is running at ~60MB/s.  I was very consistent with the 90MB/s number (I don't know why, but I would always hit the refresh button until the speed stabilized when I would start the check).  I don't have a controller or anything, so all my drives are just plugged into the mobo (I currently have a 1TB parity and 2 data disks, 1 at 1TB and another at 750GB and then new drive is plugged in and it is a 2TB drive).

 

The only thing different now is that I have an additional drive plugged into the mobo and I did unplug a couple sata cables when I added the new drive.  I thought that I might have a bad connection or something, but there is nothing in the syslog and I just figured that I wouldn't get 60MB/s with a bad connection.

 

It isn't like I am terribly upset, but curious why the speed would drop.  The new drive isn't in the array yet, but is it overloading the fetzer valve or something?  Any thoughts are welcome.

 

Thanks,

Chris

FWIW, I stopped the parity check, shut down and went in and unplugged the new drive (power and the sata cable).  Powered back up, restarted Parity and it is cruising along at 90MB/s.  Weird.

Thanks everyone. I did a "round robin" type of wiring this time, as the Wiki claims that can offer speed increases. With one card in the PCI-X 100mhz slot, and the other in the PCI-X 133mhz slot.. my parity check is going 87MB/s. I also set that bottom PCI-X 100MHz to operate at 133MHz (according to the mobo manual it won't cause issues? If someone knows that this is bad please let me know!)

 

Such a huge difference! Thanks everyone.

 

I'm glad you are working at a great speed again even though I'm a lttle surprized it made such a difference. Maybe bus contention?

 

Peter

 

 

A PCI bus is just like any other bus; it's a party line. Whatever is on it gets its own slice of CPU time, and the more parties trying to talk at once, the shorter everyone's talk time is, lest the messages become muddled and meaningless.

 

By moving the controller to the PCI-X 100MHz slot on that particular motherboard, you're actually moving it to a new bus.  In that way both controllers get full priority as needed, and the need for speed is soundly satisfied.

Byron