How to configure gigabit server/clients for best network performance?

[poohbie]

I hear that I need to make changes to the MTU, RWIN, and possibly other settings to maximize the performance of a gigabit network. And since my Win2K Server is on slower hardware (P4 2.4Ghz with 512MB RAM), enabling Jumbo Frames will help.

Can you give me advice on what changes to make to the configuration and what values to use after installing the gigabit cards?

This will be in a mixed environment of gigabit Win2K Server and gigabit/100mit WinXP clients all connected to a single unmanaged gigabit switch supporting 9K Jumbo Frames.

 

[LoStMaTt]

Does your current load ever come close to network capacity? If not then I don't think it is really worth tweaking it, performance gains will be negligible.

 

[PTNL]

Does your current load ever come close to network capacity? If not then I don't think it is really worth tweaking it, performance gains will be negligible.

Agreed. Additionally, slowness was stated without any isolation of where or how it is noticed. What is the server being used for? Are all NIC's running full duplex and GbE? Jumbo frames were mentioned, but do all attached NIC's support jumbo frames? These are just a handful of questions of many that would need answering to provide accurate recommendations or solutions.

 

[poohbie]

I'm looking to maximize file transfer speed between the server and a couple clients...thus the move toward gigabit on those computers. The rest of the clients will remain at 100mbit.

 

[sdotbrucato]

I'm looking to maximize file transfer speed between the server and a couple clients...thus the move toward gigabit on those computers. The rest of the clients will remain at 100mbit.

Being as you stated its old hardware, I think your biggest bottleneck is not going to be network performance, but HDD performance, are you even loading your current network's capacity as is?

 

[poohbie]

Yes, the 100mbit links do get maxed out. HDDs in server are in a Raid0+1 setup and its performance is not likely to be the bottleneck. Quite frankly, I wouldn't mind HDD performance ending up being the bottleneck in an optimized GbE setup, since then I'd know I've maximized the potential of GbE on my network. Making large multi-gigabyte file transfers almost as quick as if I were copying the files locally would be very nice.

 

[PTNL]

So is most of the traffic from server to client, or client to client? And d3c1ius hit a little more on the point, that the (admittedly slower) server's hardware is suspect in scalability in a multi-user environment.

In general this thread still seems awfully vague and a lot of assumptions are being made. So just working off of the assumptions from unanswered questions -- such as server load and responsibilities not being peaked, and that a managed switch is in use -- I'd suggest doing the following:
1 - Install GbE NIC's in all machines.
2 - Ignore jumbo frames.
3 - Use two identical hardware-based GbE NIC's in the server (if not already present), and setup NIC trunking between the server and the managed switch.