On December 16, 2014, [email protected] wrote: > i did an experiment a couple years ago where i booted a
> windows machine off an iscsi target connected over gigabit ethernet. > loading games and regular desktop usage was almost as good as if the > hard drive was connected to the local system. That's actually impressive. I didn't think Gigabit went that fast. I recall reading somewhere that a base rule of thumb when speaking of speeds over the network was to take the advertised speed and quarter it to get the actual usage speed. 25MB/sec isn't very fast at all these days. Even mechanical SSDs frequently read at 150MB/sec and write at 100MB/sec if the benchmarks I've seen are any indication. I may have to do some tests. Thanks! --- Dan On Mon, Dec 15, 2014 at 11:06 PM, <[email protected]> wrote: > > On Mon, Dec 15, 2014, at 11:17 PM, Dan Egli wrote: > > Does anyone know how fast of a NIC can be hooked into a USB 3.0 port? > > Specifically, I'm wondering if there's a 10GbE USB adapter for sale > > that's > > Linux compatible (you know that while most are, a few aren't or aren't > > well > > supported). > > i haven't heard of anyone making a 10gbe usb adapter. doesn't mean they > don't exist but i'd be surprised if there is one. usb3 has a max > throughput of 5gbps so one wouldn't be able to max out the link speed of > a 10gbe interface. that itself shouldn't say a whole lot though since > there are a number of gigabit ethernet usb2 adapters even though usb2 > can only do 480mbps. the bigger reason is cost. usb devices are usually > cost sensitive devices and i can't think of any 10gbe controller that is > under $100 just for the chip. even the most recent intel 10gbe > controller (which is pcie) is listed at $117 for the controller. you > would still need to add a phy and other supporting components. there are > also power requirements that would get in the way. iirc, doing 10gbe > over cat6 uses over 10 watts of power and i think usb3 can only do about > half that will also transferring data. > > > I've got a potential project here, but the machine won't have any free > > PCIe > > slots, so I'm wondering if there's a way to hook a 10GbE NIC to a USB 3.0 > > port and get reasonable speeds? The goal is to have a network with near > > SATA speeds that PXE boots all workstations (current plan is for eight, > > but > > more could be added in the future). Any recommendations are most welcome! > > I > > can't use the PCIe slot that will exist on the Motherboard because it > > will > > be filled already with a different card. > > > > i'd give it a try with just a gigabit interface first to see if that is > sufficient. i did an experiment a couple years ago where i booted a > windows machine off of an iscsi target connected over gigabit ethernet. > loading games and regular desktop usage was almost as good as if the > hard drive was connected to the local system. most hard drives can't > push much more than a gigabit of traffic anyways. ssds can go faster but > the big improvement that ssds give desktops is the random i/o > improvements. even some modern ssds can't read random i/o at a gigabit. > the speed limitation of a gigabit interface would be noticeable if > someone decided to transfer large files regularly or during some > benchmarking. > > so give it a try with gigabit. you probably will want to put a 10gbe > network adapter in the system holding the storage. > > mike > > /* > PLUG: http://plug.org, #utah on irc.freenode.net > Unsubscribe: http://plug.org/mailman/options/plug > Don't fear the penguin. > */ > /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
