Hi, thanks, what do you think about the max practical throughput of these devices if ten Gigabit clients at the same time are getting dataIf you connect two devices to same switch with Gbps ports and run test between those two devices through switch. Then configure both devices to transmit data to the other device with max possible rate of 1Gbps.
Which makes switch to handle 2Gbps in total ... while two ports on the switch are used. So average throughput per used port is 1Gbps.
The example above shows that simple calculations without considering the nature of tests may be misleading.
As to the CRS326 test results: I'd be much surprised if the test didn't use all ports, including the two SFP+ ports. And those add 10Gbps each to throughput. If you substract 20Gbps from test result (43.4Gbps), you get 23.4Gbps and divided that to 24 ports, the result is roughly 1Gbps.
As to the RB4011 test results: the bottleneck there are interconnects between CPU and both switch chips which are 2.5Gbps each. When you consider a few test scenarios you'll probably always end up with 10Gbps max throughput and it'll be a mixture of traffic between pairs if Gbps ports and traffic between a few Gbps ports and that SFP+ port.
I think the stated full-duplex speed is measured different. If the full-duplex speed is 2x the half-duplex one, and if the half-duplex one is equal to wirespeed, THEN we can say it is a non blocking switch.even more so if one skips the full-duplex BS (a packet ingressing through one port eventually egresses through another port, using up capacity of two ports hence summing up full-duplex capacity of all ports is BS)
No, that's not what they use as full duplex.@paternot: I'm not arguing usability of full-duplex port, I'm just wondering about definition of throughput in tests. I admit I've never read any test protocol specification, but from test results it seems to me that the published results are something like as follows:
Take two devices and connect them to a switch. Then start iperf in udp mode on both devices, one as server (accepting connections) and one as client (initiating connections). Then start a single direction UDP test at wire speed (e.g. 1Gbps). So 1Gbps traffic flows from client device to server device and none in reverse direction (it's UDP). For switch that's 1Gbps ingress on one port and 1Gbps egress on another port.
For me, that's 1Gbps throughput. For marketing people (and probably testers) that's 2Gbps throughput. AFAIK that's 1Gbps flowing through switch "backplane" and I guess switch will handle each packet in one single stretch ...
The only case when the full-duplex numbers would actually make sense would be if the switch/router would be source/sink of data streams itself ... meaning that data stream flowing through one port is completely unrelated to any data flowing through any other port ...
I just tried this out: works well. I had to specify different metric 1 to 5 to the now 5 GbE interfaces of the server.I want to provide as many as possible full-duplex Gigabit connections with Gigabit throughput
to a local data server. ...
Add just as many quad-port Gigabit NICs to the server and attach each
port to the switch. ... I'll try this out next week initially with just one quad-port NIC,