sudog@sudog.com writes:
> Some guidelines I've been forced into finding out for myself:
> 
> 1. RAIDFrame is a no-no on the heavily accessed drives. 

You mean mixing both a RAID component and a non-RAID partition on the same 
drive?  (i.e. where accesses to the RAID set might 'interfere' with accesses
to the non-RAIDed part of the disk?)   Also: what do you classify as 
"heavily accessed"?

> The huge
> volume of small reads and tiny writes that happen can only be handled
> on a normal ffs-based partition. 

If the file mix is such that there are lots of very small files, then even 
RAID 1 should provide performance benefits on heavily accessed filesystems.
Depending on the mix, RAID 5 should provide performance benefits for reading 
even small files... (if lots of small files are being written, then the
RAID 5 set might require more careful tuning...)

> Therefore in order to ensure minimal
> data loss, regular backups must be made.

This is irrelevant to whether or not you use RAID :)
 
> 2. With RAM at a premium, another balance must be achieved: That of
> file system caching to actual RAM. I could increase the amount of
> memory dedicated to file system caching; but this needs to be
> considered in conjunction with how many users are connected at once.
> Too much, and there's too much wastage and machinery isn't living up
> to its potential. Too little and the users can starve the system.
> 
> 3. SCSI, SCSI, SCSI. Anything less and you're spinning your wheels.
> Preferrably Seagate's new 15k Cheetah drives. 

1) How many drives?  
2) how many controllers?  
3) how many drives per controller? 
4) given 1), 2), and 3), how long before you either a) saturate a controller,
    or b) saturate a PCI (or other) bus  ;)
5) how close are you to saturating the network connection? :)

> Now those, are nice.
> Quantum Atlas V 10k are nice too but hella loud. Sounds like a jet
> fighter throttling up!
> 


Later...

Greg Oster