"Simpkins, Terry" wrote:

>   - 32 2.0Gb disks (16 mirrored to 16) on 4 F/W channels
>   - 48 4.3Gd disks (24 mirrored to 24) on 4 F/W channels
>
> We intentionally stayed with smaller drives to keep the number of spindles up.
> The production data is all on the 32 2Gb drives with 8 drives on each F/W channel.
> The 4.3Gb drives have 12 drives per F/W channel, but those are test and backup sets.
>
> What would others recommend to improve disk throughput?
> Should we replace the F/W with Fiber?
> Should we replace the HASS units with Arrays and eliminate the mirroring?

yes.  anything else? :-)

my non-scientific opinion about hass/jamaica drives is that they're sucky.  they certainly
aren't very reliable and i very much suspect that they're (way) slow.  so getting off these
drives i probably a good idea.

when we still had our 997, we seriously considered getting a va array (for the hardware
mirroring) but never implemented because we realized that even though a t-box can only push
so much io across it's backplane....we (and many of us too) effectively spread out that load
by having many scsi controllers/cards.  when we were told that "well, for a t-box all that
you need is 3 fw scsi cards (because that's all the io you can generate)....", we got real
skeptical real fast.

even now, i can't confidently say how many scsi cards -- and for hooking up to a va array
that really means how many scsi-to-fibre convertors -- you really need.  if someone is
running a non-pci system (9x8, 9x9, 99x) with a va -- please tell us how you're
configured.....

for a 959, you may easily be able to drop down to 2 or 3 scsi controllers/fibre convertors
given the capabilities/horsepower of your system.  one nice thing about switching to a va
array, for terry, is that they don't need to run mirror/ix anymore! :-)  the whole system --
including the system volume -- (thanks walt!) can be on the array.  we were very pleased
with the performance of the array when we were still connecting to it with the convertors
(and are just tickled pink now that were running pure fibre) and y'all have to suffer thru
yet another post from me on the topic :-)

do not listen to the uni-know-it-alls if they try to tell you that the disc available for
the va arrays is 'slow'.  maybe for *their* systems -- but mpe is just fine with the disc.
another thought -- on the topic of 'getting more bang for the buck' -- we've got two mpe
systems hooked to our array.  we go thru a broccade switch (to consolidate/mitigate the data
flow) but that's not a problem.  for us, it made the cost of the array much more attractive
knowing that two (and even more (ymmv)?) systems could use a single disk enclosure.

hth           - d

--
Donna Garverick     Sr. System Programmer
925-210-6631        [log in to unmask]

Come, my friends, 'Tis not too late to seek a newer world.
Tho' much is taken, much abides; and tho'
We are not now that strength which in old days
Moved earth and heaven, that which we are, we are.
"Ulysses", A. Tennyson

>>>MY opinions, not Longs Drug Stores'<<<

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