CFQ schedule of linux 2.6.13 or above kernel and NDAS driver

This is about the bug #20.

Explanation of solution

I found the solution.

The problem is that the NDAS io driver doesn't work well with "Complete Fair Queueing Scheduler" (CFQ io scheduler) of 2.6.13 or above kernel.

It works great with CFG schedule of 2.6.12 or "anticipatory scheduler" of 2.6.15 kernels.

Temporal solution is

you give

elevator=as

to the kernel parameter or

echo anticipatory > /sys/block/ndas*/queue/scheduler

at the time you enable the NDAS disk or the registered NDAS disk becomes online.

I will find more details and add the script or function to avoid this problem into the NDAS driver v1.0.1.

CodeDrop? v1.0.1 will be available by next Tuesday. March 7th 2006