Re: raid1 performance

[Bernd Eckenfels]

In article <[e-mail]> you wrote:
>> No, you just distribute the ready round robin, this means each disk has only
>> half the seeks it had before. 

> No, this is the way it was done a long time ago.

> It turns out to be an incredibly bad idea.  In fact, it is the most CPU-efficient
> way of guaranteeing the largest average seek times on your disks  ;)

> The RAID-1 code now looks at which disk worked closest to the wanted position
> last, and picks that disk for the seek.

Thats right, it is done on the distance in sector numbers. Thats a simple
compare, not sure if one could do that better.

raid1.c:raid1_read_balance()

Greetings
Bernd