Performance Notes

As a software-based product, the speed of your computer’s processor affects the analyzer’s performance. Buffer overflow errors are an indicator that the analyzer is unable to keep up with the data. The information below describes what happens to the data as it arrives, what the error means, and how various aspects of the analyzer affect performance. Also included are suggestions on how to improve performance.

The analyzer's driver takes data from the driver and counts each byte as they are put into the driver’s buffer. The analyzer's driver tells the user interface that data is ready to be processed. The analyzer takes the data from the driver’s buffer and puts the data into the capture buffer.

Driver Buffer Overflows occur when the user interface does not retrieve frames from the driver quickly enough. Buffer overflows are indicated in the Event Display window by a plus sign within a circle. Clicking on the buffer overflow symbol displays how many frames have been lost.

There are several things that you can do to try and solve this problem.

• Use capture filters to filter out data you don't need to see. Capture filters reduce the amount of data processed by the analyzer. (Ethernet Only)
• Close all other programs that are doing work while the analyzer is running. Refrain from doing searches in the Event Display window or other processor intensive activities while the analyzer is capturing data.
• Timestamping takes up processor time, primarily not in timestamping the data, but in writing the timestamp to the file. Try turning off timestamping from the Timestamping Options window.
• For Driver Buffer Overflows, change the size of the driver buffer. This value is changed from the Advanced System Settings. Go to the Control window and choose System Settings from the Options menu. Click on the Advanced button. Find the value Driver Receive Buffer Size in Operating System Pages. Take the number listed there and double it.
• The analyzer’s number one priority is capturing data; updating windows is secondary. However, updating windows still takes a certain amount of processor time, and may cause the analyzer to lose data while the window is being updated. Some windows require more processing time than others because the information being displayed in them is constantly changing. Refrain from displaying data live in the Event Display and Frame Display windows.  The analyzer can capture data with no windows other than the Control window open.
• If you are still experiencing buffer overflows after trying all of the above options, then you need to use a faster PC.