Netgear GA620 White Paper on Performance - Page 2

Back-to-Back Test, File Transfer - gigabit ethernet

Get Netgear GA620 - PCI Fiber Card PDF manuals and user guides View all Netgear GA620 manuals
Add to My Manuals
Save this manual to your list of manuals

Page 2 highlights

Chariot running against twenty-five 100 Mbps clients, Gigabit speeds are consistently reproduced in lab. Test results will vary depending on a number of factors including the type of test, the speed and performance of the computers being used, and the network topology. To measure the capabilities of the adapter, the test sho uld stress the network and not the other components of your system. Programs such as Ganymede's Chariot, and Microsoft's NTTTCP accomplish this goal quite well. These tools provide a multi-threaded, asynchronous performance benchmark for measuring achievable data transfer rate. Back-to-Back Test One test that does not accurately measure adapter performance is a backto-back test. The driver is optimized for one -to-many scenarios, so testing in a back-to-back environment will yield slower results. More than 500 Mbps throughput is still possible using a multi-threaded testing program for testing network performance, such as Microsoft's NTTTCP program. While one is unlikely to see the full capabilities of a Gigabit Ethernet card when tested backto-back, it is still possible to get a feel for the capabilities of the adapter. File Transfer Another test that does not accurately measure adapter capability is a file transfer. Copying a file from one computer to another tests a hard drive's performance rather than network performance. In a test like this, the limiting factor is the performance of the computers, rather than the performance of the network. The copying process adds the overhead of the disc drives, as well as the operating system handling the copy. The test results indicate the computers' ability to process these additional requirements rather than the abilities of the connection between them. In a test like this it is possible to see results less than 20 Mbps on any card, which is slow for both a 100 Mbps card and the 1000 Mbps card. Surprisingly, the Gigabit adapter will probably be the slower of the two cards in this test. The reason a 1000 Mbps adapter would perform below a 100 Mbps adapter is quite simple in this test. In order to achieve Gigabit performance, Gigabit adapter drivers contain additional intelligence beyond Fast Ethernet drivers. This intelligence creates more overhead than a standard 10/100 card. When stressing the network at higher speeds, this overhead is negligible, and improves to the performance of the network. When the cards are run at minimal performance, such the file copy test, the Gigabit card will have slightly more overhead than a standard 10/100 card, causing slower performance. However, as more stress is placed on the network, such as video or multiple system file transfers, the gigabit card will start to outperform a 10/100 card. Ultimately, the Gigabit adapter can deliver 10 times the network throughput of a Fast Ethernet adapter.

  • 1
  • 2
  • 3
  • 4
Chariot running against twenty-five 100 Mbps clients, Gigabit speeds are
consistently reproduced in lab.
Test results will vary depending on a number of factors including the type
of test, the speed and performance of the computers being used, and the
network topology.
To measure the capabilities of the adapter, the test sho uld
stress the network and not the other components of your system.
Programs
such as Ganymede’s Chariot, and Microsoft’s NTTTCP accomplish this goal
quite well.
These tools provide a multi-threaded, asynchronous performance
benchmark for measuring achievable data transfer rate.
Back-to-Back Test
One test that does not accurately measure adapter performance is a back-
to-back test.
The driver is optimized for one-to-many scenarios, so testing in a
back-to-back environment will yield slower results.
More than 500 Mbps
throughput is still possible using a multi-threaded testing program for testing
network performance, such as Microsoft’s NTTTCP program.
While one is
unlikely to see the full capabilities of a Gigabit Ethernet card when tested back-
to-back, it is still possible to get a feel for the capabilities of the adapter.
File Transfer
Another test that does not accurately measure adapter capability is a file
transfer.
Copying a file from one computer to another tests a hard drive’s
performance rather than network performance.
In a test like this, the limiting
factor is the performance of the computers, rather than the performance of the
network.
The copying process adds the overhead of the disc drives, as well as
the operating system handling the copy.
The test results indicate the computers’
ability to process these additional requirements rather than the abilities of the
connection between them.
In a test like this it is possible to see results less than
20 Mbps on any card, which is slow for both a 100 Mbps card and the 1000 Mbps
card.
Surprisingly, the Gigabit adapter will probably be the slower of the two
cards in this test.
The reason a 1000 Mbps adapter would perform below a 100 Mbps
adapter is quite simple in this test.
In order to achieve Gigabit performance,
Gigabit adapter drivers contain additional intelligence beyond Fast Ethernet
drivers.
This intelligence creates more overhead than a standard 10/100 card.
When stressing the network at higher speeds, this overhead is negligible, and
improves to the performance of the network.
When the cards are run at minimal
performance, such the file copy test, the Gigabit card will have slightly more
overhead than a standard 10/100 card, causing slower performance.
However,
as more stress is placed on the network, such as video or multiple system file
transfers, the gigabit card will start to outperform a 10/100 card.
Ultimately, the
Gigabit adapter can deliver 10 times the network throughput of a Fast Ethernet
adapter.