perfSONAR User Q&A and Other Discussion

[Hyojoon Kim <>]

Hello Michael, 

Okay, I think I get it. I guess it was hard to let go of the notion that if I hover of some point in a time series graph, I should only see the value that corresponds to that particular point in time. I think it used to be like that in the pervious perfsonar version. 

Thank you for the clarification. Good to hear that improvements are planned :-) 

Thanks, 

Joon 

On Apr 19, 2017, at 4:39 PM, Michael Johnson <> wrote:

Hi Joon,

It’s mentioned in the docs (see below), but let me try to explain. What you are seeing is one line *per test* that the graphs see. Keep in mind that all your tests would be newly created upon upgrade to 4.0, and that any time you change a test parameter, those values show up as a new test. The easiest way to see which values correspond with which points on the graph is to move your mouse and watch for the values to change. Then you know you have found the actual values for that test.

There are some improvements planned to this, both in terms of only showing values relative to the current time in the timeline, as well as to help visualize which values are currently being displayed.

Let me know if you have other questions.

From the documentation, in the “Things to note” section:

The numbers in the overlay box are the “last known values.” One might expect that if there is no value for a test or quatity, such as retransmits, at the crosshair, no value would be shown, but instead, the last known value is shown. For example, at a point in the graph, there may be two distinguishable -> Throughput (TCP) values in the overlay box, but only one line. If you mouse back and forth, you’ll see that one of the values is not changing. This indicates that that particular test ended some time ago and the value being displayed is its ending value.

Thanks,

Michael Johnson

GlobalNOC Software Engineering

Indiana University

812-856-2771

On Apr 19, 2017, at 1:16 PM, Hyojoon Kim <> wrote:

Hello, 

As in the attached image, we see lots of lines/entries in the overlay box. I understand there will be lines for different directions (-> and <-), but I am not sure with other lines. Could someone explain this to me? 

For example, in "Loss- ipv4", why are there multiples lines with different Ns of “0 of N packets”? Also, even with a single N value (e.g., if N=80, 0 of 80 packets), why are there duplicate entries with same direction? For example, there are two lines of “<- 0% lost (0 of 80 packets)(ping)”. 

Same question for “Latency - ipv4” category. I’m not sure why I am seeing so many lines here. 

I looked up the documentation here, especially in “Things to note” (http://docs.perfsonar.net/using_graphs.html), but I still cannot understand how to interpret this overlay box. Some explanation would help! 

Thanks, 

Joon 

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