configuration choices with Dell CERC (adaptec 2610SA)

[Herve Boulouis]

Le 26/11/2005  14:17, user a écrit:
> 
> Read caching: yes/no (default is yes)
> 
> (read caching does not rely on a battery, and is completely "safe",
> right?  I am going to set this to "yes", however I wonder - why would
> anyone _ever_ set it to "no" ?)
 
You usually want to disable read caching on all aac based adaptec raid
controllers because it decreases performance.

> Write caching: enable/disable
>
> (this is the one that can get you into trouble if the system loses power
> before a write is committed to disk, and the battery is dead, right?  I am
> going to set this to "disable" because I do not think the 2610SA has a
> battery ... right ?)

If your server is plugged on a UPS you can safely enable it, it's quite
a performance gain.

> Rebuild rate: high/medium/low
> 
> (I have no idea what this means - I never saw this in adaptec bios before
> ... can anyone define exactly what this means ?)

This controls how much ressources the card will put in rebuilding a volume
that got a failed disk. A high rebuild rate will mean a short rebuild time
but slower disk accesses during the rebuild.

-- 
Herve Boulouis