Skip navigation
All Places > Licensing and Installation > Blog > 2014 > March

I've been doing a lot of work analyzing network performance lately, and I'm always looking for new ways to gather and help me analyze data quickly. In this Tip of the Week, I'll feature a tool I've recently come to appreciate called 'PingPlotter'.


Under the hood, PingPlotter is just tracert pretty much. But the value add for the tool is how it shows you the data. With PingPlotter you can define the number of samples you want, the frequency of the samples, and what you think are good, acceptable, and poor performance ranges. When you run your trace, PingPlotter shows the data in a graphical format and also gives you the minimum, maximum, and average values. Have a look at the graphic below, where I tested my connection to





Good stuff, yes? And that's just the freeware version. There are premium versions with some really nice features like the ability to define multiple targets and trace several at the same time.


Check out the freeware version here:



By the way, I'm always on the lookout for useful tools to help troubleshoot issues or evaluate hardware and network infrastructure. If you have a favorite, by all means post it!


Best regards,


Ken Foster

Mentor Graphics Customer Support

If your PC seems sluggish, use RESMON to uncover the bottleneck.

Click Start, type RESMON and press Enter to launch the Resource Monitor. Click the CPU, Memory, Disk or Network tabs. Windows 7 will immediately show which processes are consuming the most system resources.

The CPU view is particularly useful, and provides something like a more powerful version of Task Manager. For example, if a program has locked up, right-click its name in the list and select Analyze Process. Windows will then try to tell you why it's hanging (the program might be waiting for another process) which could give you the information you need to fix the problem.

Resource monitor keeps a careful eye on exactly how your PC is being used.

One of the first questions to ask when investigating performance issues is “Which license server is the tool looking at?”


Very often, the answer is “It’s looking at the right server, but it’s checking it a number of times for each license”.


On Windows, Mentor tools typically look for licenses in five locations:



  • MGLS_LICENSE_FILE environment variable
  • MGLS_LICENSE_FILE registry value
  • LM_LICENSE_FILE environment variable
  • LM_LICENSE_FILE registry value
  • C:\flexlm\license.dat



(On Linux / Unix only the environment variables are used.)


If your license server is listed in both the environment variables and both registry values – then the server can be checked four times for every license request!


Some tools check a number of licenses to determine what options are available, so if you do not have that license, you are getting the same “No license here” answer four times.  (If a license server is listed multiple times in an environment variable – it can be checked even more often.)



Each license server only needs to be listed once.  If a server is listed more than once, remove the duplicate entries.

The MGLS_LICENSE_FILE variable / registry value is only used by Mentor tools, whereas the LM_LICENSE_FILE settings are used by all tools that use FlexNet.  (If you only want Mentor tools to check Mentor license servers, define the Mentor license server in MGLS_LICENSE_FILE, and set MGLS_LICENSE_SEARCH=1 to stop them checking LM_LICENSE_FILE.)


How to make the changes


The Mentor Licensing Utility provides a simple method of editing your license variables.

Use it to remove any duplicate entries.  In the example below, the two highlighted entries can be removed.




If you're looking for information on any of the following PADS Flow installation and licensing topics, click on over to the PADS Install and Licensing page!


  • Important licensing changes in the latest release
  • How to install the PADS Flow software
  • Best practices for the installation
  • Installation and licensing changes and transitions
  • Configuring licensing (for the PADS user and the license server administrator)
  • Common PADS licensing problems



If you're navigating from the main 'Licensing and Installation' page....


Last week, Ken Foster showed us how to use psping on for measuring network latency on Windows - Tip of the Week: Measuring Network Latency. On Linux you can use ping with specific options to achieve similar results.


For example:


     ping -U -q -c 300 -s 1200




The options are as follows:


-U display full user-to-user latency, not just network round trip time.


-q Print only the first line and the summary


-c The number requests to send at one second intervals (300 = 5 minutes worth)


-s The number of bytes sent for each ping


rtt is ‘round trip time’. The values that follow are the minimum, average, and maximum latency values in milliseconds.



Please see previous blog posts on latency:


Tip of the Week: Troubleshooting Networking on Windows with pathping.

Tip of the Week: Measuring Network Latency