how to maximize performance?

[I-I-Ice -now that's refreshing.]

Could someone help me please?

I have been trying to figure out the best way to install 386ix and I am 
confused.

My system has an Adaptec 1542B, 4 megs of ram, with device 0 being the
ST296N (access time 28 ms) and device 1 the CDC (access time 18 ms).

I would like to put the Unix system itself on half of one of the drives (I
currently have 2 40 meg partitions on the 296N, and I would like to do the
same for the CDC), and put my user files on the other drive.

If I understand this correctly, then SCSI can send multi-threaded I/O
requests which can be processed by both devices simultaneously, rather than
all the I/O burden on one drive. As the cliche goes, two heads are better
than one.

But all this would be easy if the drives were the same, but they are not;
there are performance differences; and I do not know what portion of Unix
to put on which drive to guarantee best performance. Transfer rates for 
the two drives are:

296N:	I/O Trans. Rate (Mbytes/sec)	1.5
	Int. Trans. Rate (Mbits/sec)	10

CDC:    I/O Trans. Rate (Mbytes/sec)    1.25
        Int. Trans. Rate (Mbits/sec)    10

Finally, here is a transcript of a conversation with a friend of mine
about this.

Please reply to me privately, and if justified, I will re-post.
Thanks very much.

Ice.

-----------------------------------------
sasingh> Also question. Would it not make more sense to install Unix on
sasingh> the CDC Wren, since it has the faster mechanical access time?
sasingh> Unix is about 200 little programs, so a high transfer rate is
sasingh> not as important as finding the data quickly.

That would be true, but ...

sasingh> And swap space would be better utililized by the 296N since it
sasingh> has a slightly higher transfer rate than the CDC, but a slower
sasingh> access time; but since swap space is one big chunk, the slower
sasingh> seek time should not be a liability, since the head is usually
sasingh> going to be centered right at the beginning of the swap file
sasingh> right?

Well, actually, it depends on how they implement swap.  But, I'm pretty
sure that typically, the disk has to see back and forth to get to the
appropriate swap sector, and then read it.  You swap is big, right?  But
any swap block is relatively small.

As for Unix being lot's of small files, that is true.  But one small
file load will not matter much if you start swapping.  You'll notice a
significant speed decrease when you start swapping (as you could
probably guess) so optimizing that is more important.

As least that's how I'd do it.