[lug] Software RAID5 performance

[Daniel Webb]

My knowledge of kernel workings is not that great, but doesn't the kernel
buffer all block devices in memory?  I think the new kernels (2.4+) are fairly
aggressive in their block buffering too, or at least I assumed that's why my
memory usage was so high in the "top" memory usage.

I think you have to use software that's designed specifically to test drive
performance to find the actual transfer rate.  I have always used hdparm, but
that may only work right directly on IDE devices, I'm not sure.  

Daniel