SystemView Overflows

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During a SystemView recording, SystemView Overflow Events might be recorded, indicating that some events on the target system could not be recorded.

SystemView Overflows can happen when the target application generates too many events to fit into the target SystemView buffer, or when the buffer is not read and cleared fast enough.

Generically, to prevent or minimize overflows:

  • Chose a larger target SystemView buffer.
  • Minimize the amount of events, e.g. disable some events in the system.

Overflows with J-Link Recorder

When recording with J-Link, overflows can happen when:

  • The J-Link target interface speed is too low to read the data fast enough.
  • The J-Link is kept busy by a debugger and cannot read the date fast enough.

To prevent or minimize overflows:

  • Select a higher J-Link target interface speed in all instances connected to J-Link.
  • Minimize the interaction of other tools with J-Link while the target is running.

Overflows with IP Recorder

When recording via IP with the communication task reading from the target SystemView buffer, overflows can happen when:

  • The communication task is blocked or delayed for too long.
  • The communication task reads and sends not enough data per invocation.
  • The bandwidth limit is exceeded and not all data can be sent.

To prevent overflows with the IP Recorder:

  • Raise the priority of the communication task to be not blocked or delayed.
  • Increase the amount of data to be sent at once.
  • Decrease the delay of the communication task between sending.
  • Make sure no other data is sent on the Ethernet connection to the host.