Well here is the summary for what it is worth.
Original question:
I am in the process of upgrading my Alpha Server 2000, 128MB memory, 1
233 CPU, 4 4.3 GB raid5 disks, 4.0g to a faster system.
I am proposing 128MB memory, total of 2 233 CPU's 4 9.0 GB raid5 hard
disks.
I need to know how I can calculate how much time will be saved if I do
this upgrade. I know I can cost justify it by the $ wasted in waiting
on
nightly processing (the plant needs the system up at a specific time
and
if it isn't that is $$)
I know the amount of memory I am swapping out, Where do I start?? I
need
to know yesterday. :)
Thanks to : Alan _at_compaq, Dr. Thomas Blinn, Jim Belonis, Tony McElhill,
Joe Fletcher, and Pat O'Brien
Quick answer. It is impossible to tell. Nobody on earth can tell what
will happen.
After research and studying the numbers answer: I am wasting my time and
money by performing this upgrade. It won't help my system at all.
to see if an additional cpu will help (I am using the collect utility)
I looked at the User + Sys times. My average for a month is 36%
I also looked at the Idle + Wait times. My average is 63%
Also look at runq time. My average is 0.99
to see about the memory look at the memory portion of collect.
Look at device activity of the swap space device if seperate. mine is
seperate avg of 1.26%
Also look at the paged out (PO) section. My avg is 0.13 MB / Sec.
Hard drives
Look at the i/o rates on the specific hard drives. If you are using a
faster one then it might help. Can't determine it.
Tape drives
Look at the I/O rates on tapes. (have to catch them when they are
actually busy). If a tape drive is faster more reliable it will help but
how much to be determined by adding the tape drive and then watching the
before and after results.
>From Jim Belonis
First you need to know what bottleneck there is and whether the
specified upgrades will address it.
If your bottleneck is disk I/O, then your upgrade probably won't affect
it much.
If your bottleneck is CPU, the 2nd CPU might help.
If your bottleneck is swapping, the upgrade probably won't help,
you would need more RAM instead.
If your 'nightly processing' takes all available CPU time
for protracted periods, and it can be helped by two CPU's
(i.e. multiple processes are running at once, or a single
process has been written to take advantage of multiple CPU's)
then hot damn ! you're in business.
Calculating how much time will be saved is MUCH more difficult.
It probably can't be done without sticking in a 2nd CPU and
experimenting.
Talk to Compaq (or is it Intel now ?) and see if they will lend you a
CPU
to test, or can find a dual-processor system you can test on.
Or buy a 2nd CPU with the guarantee that they will take it back
if it doesn't help.
Jim Belonis
Ron Bramblett
Systems Administrator
Fuller Brush Company
Received on Thu Jul 26 2001 - 14:53:08 NZST