> > I've gotten confused on this problem way too many times.. I'd like to > get some definitive starting points. > > When you see net adapters online they are always rated like > > 10/100 or 10/100/1000. So how does one turn that notation into > megabytes? >
That notation is in megabits per second, or Mb/s or Mbps. Bits are shown as lowercase b and bytes are shown as uppercase B. So you want to change Mbps to MBps. This is stating the raw throughput, so Ethernet headers are included. > But still, when I'm trying to measure how much data is moving to a > certain directory, and I want to compare it to what the adapter is > supposed to do... (in some easy homeboy way). > > I vaguely remember something about 8 bits to a byte or maybe its the > other way round... > Yep - 8 bits to a byte in this case. Serial comms can be a different number of bits per byte. > > My homeboy transfer measurements: > > I measure the incoming MegaBytes as measured with `du' with a while > loop interating in settable intervals. So in this case when set to 60 > seconds,I now the number of megabytes that arrive in 60 seconds but > would like to know how to convert that to the other notation. > du is probably not a good way of doing it, depending on how the disk system commits the writes. Some clients show you the data rate. Maybe wget or ssh? Cant check where i am now. Thee numbers the application states (or du) is just the data, so doesnt take into account ethernet, IP and TCP headers. > > I'm seeing between 222 and 237 MB in a full minute being transferred > and it seems quite slow for what is supposed to be a gigabyte network. > > This is just across two computers on my home lan, both with gigabyte > adapters and they connect thru a gigabyte switch. Or I hope they are. > > My setup looks like this in brief (simplified). > > > IIRC typical speeds on 100Mbps LANs are 4 or 5 MBps. There's many factors that can affect speed tho.
