TS sizing?

[M$]

I'm looking for advice on how to size a TS.

The requirements are:
- W2k server std
- 20 users
- Office 2000 std
- MS Access runtime
- Acrobat reader
- Rumba Vax Terminal emulator
- 4 or 5 Financial apps written mostly in VB and some may use a MS Access
mdb as a DB
- Users typically have 4 to 5 apps open at any one time (eg. outlook,
Terminal emulator, word, acrobat, IE, etc)

I'm aware of the Microsoft specs for sizing a TS, and I also have several TS
that I setup based on the MS specs, but when the number of connected clients
exceeds about 10 they start do severely depredate in performance to the
point that they grind to a halt when the number of clients goes above 12 to
15. I also noticed that Acrobat Reader sometimes seams to hog the CPU to the
point that all other processes have no CPU allocated to them.

Please share you experience in TS sizing and what configuration works best
for you? What are the bottle necks to watch out for?

Thanks,

 

[Matthew Harris [MVP]]

Asking how big a terminal server need to be is almost an
impossible question to answer.

You should assume each user is going to consume about 20-
50MB of memory each, and the OS will consume about 100-
200Mb of memory.

Many programs frequently misbehave. Having two processors
is a very good idea to prevent one thread from stalling
your system, although as long as there are applications
that misbehave, there isn't going to be a perfect solution.

One thing to look out for is that you should use server
quality parts in your terminal server. This especially
includes high performance gigabit (or other high
throughput) network cards that can support processor
offloading and support bigger buffers and MTU sizes.

-M

 

[Jeff Middleton [SBS-MVP]]

I have a number of sites running the configuration of apps you listed,
several of the servers were deployed over 2yrs ago and so the RAM was more
expensive to deploy at that time, but these are Dual PIII 933 Mb with 512Mb
RAM on a SCSI RAID. The systems typically cruise at 20-35% CPU, spikes
rarely hold over 80% more than a second or so, and typically no noticeable
change in performance in the sessions is demonstrated. Acrobat, depending
upon version, can misbehave and even start into a memory bloom you have to
just kill off, but an upgraded version of Acrobat Reader would probably
solve that. Print drivers can be the killer in the design, so watch for
that relationship to Acrobat if you are running distiller.

I would always recommend a dual CPU as a minimum to smooth out the service
per session.

Not that I'm recommending it, but I have a Dual PIII 1Ghz with 1G RAM that
runs 50-60 sessions of this type, pretty much in the 45-55% CPU range. That
system is scheduled to be split to a pair of Win2003 Apps server soon....but
it still holds it's own....with 50 users running various combinations of
Office apps in every session. It's a little scary to watch the summary list
of processes on that box.