IDE -- mount partitions for better performance

[freebsd_user at guice.ath.cx]

Annotated below ...

> Hi,
>
> On Tuesday 15 March 2011 07:00:30 freebsd_user at guice.ath.cx wrote:
>> freebsd-questions at freebsd.org
>>
>> Guidance with the following:
>>
>> We are limited to Support for ATA-100/66/33 IDE and ATAPI compliant
>> devices.  With that said, we have our atapi/33 optical on a add in
>> controller (PCI) and are seeking to place four HDD’s on the main boards
>> controllers.  Our dilemma is where to place /, /tmp, /usr and /var from
>> a
>> performance standpoint.  We understand that /var  does quite a bit of
>> writing and probably should go on the master hdd, but what about the
>> /usr,
>> /tmp and root?  Hell, I’m not sure my thinking is sane as to where I
>> ‘think’ /var should be placed/mounted.
>>


> did I get it right? You have four hard disks?

Yes, four separate HDD's

>
> If so, place /, /var /tmp on indiidual drives. Make the fourth disk usr
> and mount the remaining space of the other three disks inside /usr/home.

Are you suggesting something similar to:

/dev/ad4s1a for /
/dev/ad4s2a for /tmp
/dev/ad4s3a for /usr
/dev/ad4s4a for /var

If so, my initial can current concern is which device (hdd) from the above
list/configuration, should be connected to which cable connector (master
or slave)? --depending on how much writing to a particular device is
taking place; for instance during a 'build world' or while building
anything from src. there is quite a bit of writing going on.  I would
think that making the disk/slice that is being written to a slave would
decrease performance when the master to that slave is also being written
to simultaneously.  In such a case the slave would need to wait until the
master is done writing before the slave would be able to write;  Is my
thinking on this sane?

Please enlighten me/us.

Thank you.
>
> Locate then stuff on the other three disks which you expect to be used in
> parallel with the /usr disk.

I'm lost on the above suggestion; not understanding this.
>
> Of course, you can mount it anywhere else if you want.
>
> Erich
>
>