How to improve gigabit jumbo frame performance

[Guy Scharf]

I have a workgroup network running Windows XP Pro on all machines. Two
computers have Marvell gigabit ethernet adapters on board with jumbo
frames (9k) enabled. All computers are connected through a single
Netgear GS108 switch, which supports jumbo frames. TCP parameters on
all machines are at their default values.

One of the two computers is serving both as a workstation and as NAS
for one other computer.

When transferring files, Task Manager's Networking page shows 26% to
27% busy on the network adapters. Ethereal confirms that jumbo frames
are being used.

I am wondering if there is a way to improve throughput, perhaps
doubling or even tripling it. I particularly want to optimize transfer
rates between one workstation and the other that serves as both
workstation and NAS. Is this possible?

Two possibilities that occur to me are to increase the TCP receive
window or to connect the computers directly, bypassing the switch. Is
either approach likely to improve throughput?

Both computers have two ethernet ports, so the hardware capability
exists, but I am uncertain how I would need to configure TCP to support
effectively two connections between the systems. Would I just use
static IPs for the second connection, outside the subnet used for the
rest of the network? Would this be likely to improve performance?

Or, what else should I try?

Thanks!

 

[Guest]

Hi Guy Scharf,
Could you please let me know either your Marvell Gigabit
Ethernet adapters support Teaming? if Yes than you may go for Link
aggregation using Cross Over Cable using Single IPs & there will be no need
to apply each IP to each Adapter just enable Teaming to increase your Data
throughput. By the way you may use Intel's Ethernet Adapters & they support
Teaming & other featuers which may helpfull to you.

 

[Guy Scharf]

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Hi Guy Scharf,
Could you please let me know either your Marvell Gigabit
Ethernet adapters support Teaming? if Yes than you may go for Link
aggregation using Cross Over Cable using Single IPs & there will
be no need to apply each IP to each Adapter just enable Teaming to
increase your Data throughput. By the way you may use Intel's
Ethernet Adapters & they support Teaming & other featuers which
may helpfull to you.

Teaming is an interesting idea I had not thought of. However, while
one system has two Marvell gigabit NICs on board, the other has only
one, plus an old 10/100 3Com card. So I don't think the available
hardware would be suitable for teaming, even if it supports it (I don't
know).

I'd be happy if I could just improve throughput on a single gigabit
connection. This falls in the category of "nice to have" rather than
"essential," so I am trying to find an inexpensive solution.

Guy

 

[Jack \(MVP-Networking\).]

Hi
No crossover cable is needed when you connect Giga cards. Giga hardware is
MDX by standard( in other words it is automatically sensor and adjust the
type of connection).
Current Giga hardware when use with client OS is not really a huge improving
over 100mb/sec. (life in the fast lane is not the Giga way yet ). Home
Giga Network: http://www.ezlan.net/giga.html
Giga networking - http://www.ezlan.net/giga_net.html
Jack (MVP-Networking).