[ On Thursday, April 10, 2003 at 16:23:45 (-0700), Caffeinate The World wrote: ]
> Subject: RAIDFrame in Production Use
>
> If you have experience in using RAIDFrame in production, I'd like to
> know what your thoughts are. 
> 
> I hear it is CPU intensive, how intensive is it?

I'm using RAID-5 on a six-spindle RAIDframe partition for /home on my
main server.  I've been using it quite happily for over a year and a
half now.

I haven't noticed it eating huge amounts of CPU, but /home is one of my
less active partitions, at least at any time when the CPU is chewing
hard on things like compiles which happen on other partitions....

The system is a Pentium-II running at 300MHz with 320MB RAM.  These six
disks (plus one hot spare) in the RAIDframe configuration are all on a
separate SCSI host adapter:

ahc1: aic7880 Wide Channel A, SCSI Id=7, 16/255 SCBs
scsibus2 at ahc1: 16 targets, 8 luns per target
sd6 at scsibus2 target 0 lun 0: <QUANTUM, XP34550WD, LYK8> SCSI2 0/direct fixed
sd6: 4341 MB, 5899 cyl, 10 head, 150 sec, 512 bytes/sect x 8890760 sectors
sd6: sync (100.0ns offset 8), 16-bit (20.000MB/s) transfers, tagged queueing
sd7 at scsibus2 target 1 lun 0: <QUANTUM, XP34550WD, LYK8> SCSI2 0/direct fixed
sd7: 4341 MB, 5899 cyl, 10 head, 150 sec, 512 bytes/sect x 8890760 sectors
sd7: sync (100.0ns offset 8), 16-bit (20.000MB/s) transfers, tagged queueing
sd8 at scsibus2 target 2 lun 0: <QUANTUM, XP34550WD, LXY4> SCSI2 0/direct fixed
sd8: 4341 MB, 5899 cyl, 10 head, 150 sec, 512 bytes/sect x 8890760 sectors
sd8: sync (100.0ns offset 8), 16-bit (20.000MB/s) transfers, tagged queueing
sd9 at scsibus2 target 3 lun 0: <QUANTUM, XP34550WD, LXY4> SCSI2 0/direct fixed
sd9: 4341 MB, 5899 cyl, 10 head, 150 sec, 512 bytes/sect x 8890760 sectors
sd9: sync (100.0ns offset 8), 16-bit (20.000MB/s) transfers, tagged queueing
sd10 at scsibus2 target 5 lun 0: <QUANTUM, XP34550WD, LXY4> SCSI2 0/direct fixed
sd10: 4341 MB, 5899 cyl, 10 head, 150 sec, 512 bytes/sect x 8890760 sectors
sd10: sync (100.0ns offset 8), 16-bit (20.000MB/s) transfers, tagged queueing
sd11 at scsibus2 target 6 lun 0: <QUANTUM, XP34550WD, LYK8> SCSI2 0/direct fixed
sd11: 4341 MB, 5899 cyl, 10 head, 150 sec, 512 bytes/sect x 8890760 sectors
sd11: sync (100.0ns offset 8), 16-bit (20.000MB/s) transfers, tagged queueing
sd12 at scsibus2 target 8 lun 0: <QUANTUM, XP34550WD, LXY4> SCSI2 0/direct fixed
sd12: 4341 MB, 5899 cyl, 10 head, 150 sec, 512 bytes/sect x 8890760 sectors
sd12: sync (100.0ns offset 8), 16-bit (20.000MB/s) transfers, tagged queueing


> What do you use for hot swappables with NetBSD? Any power down
> necessary?

My disks are in a rackmount chassis with Kingston (StorCase) DataExpress
DE100 hot-swap bays with the optional SCSI isolator board on the back of
each module, so they are definitely true hot-swap drives.  With this
kind of hardware all that's needed after a device change is a quick
re-scan of the SCSI bus with scsictl.

-- 
								Greg A. Woods

+1 416 218-0098;            <g.a.woods@ieee.org>;           <woods@robohack.ca>
Planix, Inc. <woods@planix.com>; VE3TCP; Secrets of the Weird <woods@weird.com>