Hi,
I will shortly be adding a second 5 bay SCSI backplane to a server I have.
I am currently have one 5 bay backplane with five drives attached - one
4.5 Gb boot drive, three 9Gb drives in a RAID 5, and one 4.5 Gb unused
drive that will eventually be used in a RAID 1 to mirror the boot drive.
The second backplane will have 5 9Gb drives in a RAID 5 to start.
Questions:
To improve redudancy and speed, I would think I want to split up the
drives across the different controllers, i.e put one 4.5 Gb drive on
backplane 1 and 1 4.5 Gb drive on backplane 2 and split the 9Gb drives
across the backplanes as well. The controllers are embedded Symbios
53c875's. I assume moving the drives will reorder the SCSI devices, so
that what was one sdb may now be sdf for example. Is that a correct
assumption and is my logic regarding redundancy and speed correct?
Secondly, I will be using the arrays for file serving to SMB and
Appletalk/Appleshare IP clients. What chunk size would one recommend for
such a setup? Files will range in size from 1k to roughly 50-100Mb.
Also, some clients can only accurately see 2Gb partitions. Will I take a
big performance hit if I partition what would originally be one big RAID 5
composed of 9Gb drives into smaller chunks composed of partitions of the
9Gb drives?
Thirdly, anymore performance boosting suggestions? Here are my bonnie
stats - I can't really say I know if what I'm seeing is good or bad. Can
anyone comment on good or bad for my hardware? Is CPU usage high because
this box is currently under little load and the test uses all the CPU as a
result? Hardware info:
Intel BalboaII Chassis with 2 5bay SCSI backplanes
Dual Pentium II - 300Mhz
512Mb RAM
Symbios 53c875 SCSI controller (2 on motherboard)
-------Sequential Output-------- ---Sequential Input--
--Random--
-Per Char- --Block--- -Rewrite-- -Per Char- --Block---
--Seeks---
Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec
%CPU
100 5272 93.0 98596 100.1 27304 98.1 5219 90.3 140042 99.8
4436.3 170.8
--
~ Kevin M. Myer
. . Network/System Administrator
/V\ ELANCO School District
// \
/( )\
^`~'^
