Tuesday, October 27, 2009

Network Saturation Finally

I have finally achieved my goal of network saturation on my home network.
As with most people, I have a small off-the-shelf router that does the standard 100 Mbs. Most of the computers in my house are hardwired because the wireless signal is slower and weaker in the far corners of the house and also because we bought a spec home that had all the rooms pre-wired with Ethernet.
In the past, when I've been copying files from one computer to another and I've looked at the transfer rate over the network I've been disappointed that only 40% to 60% of the available bandwidth was being utilized. The hardware supports 100 MBS so why isn't it transferring data at that rate dammit?
The reason is because of the slowest component in the chain which has always been the hard disk speed. Well not anymore. I've just bought myself a new computer and with this I got a Patriot Torqx PFZ128GS25SSDR 2.5" Internal Solid state disk (SSD) which promises 260 MBS read and 160 MBS write.
The computer that I was copying from had the data sitting on a Seagate Barracuda LP 1.5TB 3.5" SATA 3.0Gb/s Hard Drive -Bare Drive. I don't know what the read speed of that is (yet - I'll come back and update this later) but I'm guessing that it's over 100 MBS or I wouldn't have achieved network saturation.
Is it going to be worth getting a faster router? Not yet I think. The times I'll be copying between computers with fast hard drives is probably going to be rare. I'll wait until my internet connection exceeds 100 MBS. My prediction is that will happen in about 7 years time.


  1. Interestingly there was an article here www.readwriteweb.com/.../google_web_in_f where Google CEO Eric Schmidt says "Within five years there will be broadband well above 100MB in performance - and distribution distinctions between TV, radio and the web will go away."
    In five to seven years time I will revisit this and see if Eric Schmidt's well informed comment is more accurate than my thumb suck guess.

  2. what kind of bottlenecks did you find? Was it simply the hard drive? I am suffering similar "setbacks" at my office trying to maximize backup times and am seeing a max throughput on the server nic of about 25%. Really chapping my hide... Got any hints?

  3. @Martin - Yes - it was just the speed of the hard disk. As soon as I put faster hard disks in my machines I managed to saturate the network and move the bottleneck to the NIC's. The machines that I haven't upgraded the hard disks on still run at around 25 to 50% of network capacity.
    The other thing that you can look for is if you've got two switches or routers communicating with each other. If they are set to auto negotiate the highest speed possible then this usually works but sometimes their "intelligence" isn't that intelligent and they negotiate the lowest or a lower speed. In cases like that you can manually configure them to run at the highest speed that the slowest of them runs at which may well be higher than auto negotiate.