[rescue] Re: Ultra 10, again (won't this guy ever shut up?)

[Patrick Giagnocavo]

>
>> Can I swap these drives for faster ones? They're Ultra ATA33, and now
>> there's Ultra ATA<something faster>. Anyone know? Or is the bus speed
>> the limit? I don't know these things, the only IDE I have is in my
>> laptop and a Javelin Wedge.
>
>I don't know that it will make a big difference. To optimize your
>performance, you might consider putting two suitably sized whatever disks
>(ATA33/66/100) in the system, manually mirror your little root partition
>(nightly mount/ufsdump|ufsrestore/umount) and use disksuite to mirror your
>other partitions across the disks. Maybe even hang one of the disks on the
>secondary controller (along with the CDROM) to spread out the buses.

There are 5400RPM IDE drives, and 7200RPM IDE drives.  The 7200's are
definitely faster :-)

You might want to look over the docs on the IDE setup - if you can get it
set for "UDMA-2" mode or any mode above that, performance increases and CPU
usage goes down (barely above cpu usage for SCSI, at least on x86 hw, but
it depends on Sun's driver in this case).  If it is set for the earlier PIO
modes (0-3) then you have turned your lovely SPARC chip into a high end
disk controller whenever you transfer data.

The difference is that UDMA2 + modes send one interrupt per transfer
request, rather than the PIO modes sending one interrupt per block transfer
(I think every 512byte or 1k transferred would generate an interrupt in
that case).

Cordially
--
Patrick Giagnocavo
patrick at zill.net
Web Hosting:  http://www.zill.net/