Port detail Flow Control

[Mike]

First let me say there is NO issue with Netonix Switches and I am aware of that. Any bad data comes from the connected device or network layout etc..
This is to help people (myself included) understand some of the stats on the Port detail.
These images come from an incoming Air Fiber port that feeds the switch. The router is at the other end of the Air Fiber link.
I attached two images. One with flow on and one with flow off. I took screen shots when the RX packets were about the same. As you can see most numbers line up pretty well.
The major differences are:
Flow on had lots of TX pause
Flow off of course had zero
Flow on however had 0 RX drops
Flow off had over 30,000
Difference in TX packet total. With Flow off its about 1/3 of the amount of packets.

My 2 questions are;
The TX packet total being so much less with flow off is that because there is a bunch of retransmissions due to pause frames with flow on?
Which is the better scenario having lots of pause frames or lots of RX drops? Juts what is an RX drop?

Mike

[Mike]

no comments?

[Julian]

Well, in this case, I think you need to do some real world testing to see what the effects are on throughput, and go from there.

As far as I can tell, and as you probably are already aware, you have one end of a link downmodulating or the link itself degrading, due to interference or some other factor. This makes pause frames, if FC is enabled, or just gives you RX drops, since TCP/IP checks for this type of issue on its own.

Theory would state that FC is quicker than allowing inbuilt error correction to be your sole defense, since usually it's an entire group of packets that gets dropped if error correction has its way. Theory's usually about half right, though.

[mike99]

With FC on, paquet are still drop but it's done on a other device instead. FC only make sence if the device that will insead drop paquets can do QoS. I had begin testing FC obey only + QoS on the WISP switch. That would have been a great option but I currently don't have much time to continue testing.

[Mike]

I have all gig equipment and that AF link is super solid always 8x never had an issue and scans show no interference. Steady 55 signal. All the other ports on the switch show no flow control errors it's only when it hits the air fiber which I know has FC issues. So with FC on, the amount of pause frames looks extremely high almost as many as total packets could that be OK?
Also the difference in TX total is 1/3 as much with flow off can someone explain that?

[sirhc]

Post a screen grabs of the port details on the AF port and any other port that shows Tx or Rx Pause frames

[Mike]

Those screen grabs I posted was the air fiber port and there are no other ports with pause frames. Those 2 images are the same radio I just reset the counter and waited till it received about the same packets and grabbed another image to compare.
Flow off and a Flow on image grab.

Mike