Developer Guide

  • 2021.1
  • 11/03/2021
  • Public


This topic covers troubleshooting for the data streams optimizer.
Possible Cause / Solution
Environment file parsing error due to mis-formatted JSON.
Cause: File contains one or more invalid JSON characters.
Solution: Escape JSON-specific characters such as double-quotes and backslash:
  • For double-quotes
    , replace with escape symbol:
  • For backslash
    , replace with escape symbol:
FileNotFoundError: No such file or directory: “some_path” after the capsule generation step.
Cause: Path mismatch between the capsule_generate_command (-o option) and capsule_host_path in the environment file.
Solution: Make sure the values in the capsule_generate_command (-o option) and capsule_host_path match in the environment file.
Workload exit status is 127.
Cause: Permission issue.
Solution: Make sure you have “execute” permissions for the workload validation script.
Capsule generation script exit status is 127.
Cause: Permission issue.
Solution: Make sure you have “execute” permissions for the subregion capsule script (
“no module named …”
Cause: Prerequisites are not satisfied.
Solution: Follow the steps in the prerequisites section of
Failed to reconnect via SSH after reboot.
Cause: IP address changes after reboot.
Solution: Use a static IP address for the target system or use the full hostname to establish the SSH connection.
“Failed to generate capsule.”
Cause: Subregion capsule tool issue.
Solution: Check that instructions from
was executed correctly and check paths in environment file.
Some streams are missing in the tool flow log.
Cause: In the requirements file, these streams lack unique IDs.
Solution: In the requirements file, make sure that each tccRequirements field has a unique ID.
After disabling RTCM, the system freezes or the following error occurs: “Could not set up firmware update: Invalid argument. ERROR: Failed to apply buffer capsule”.
Cause: In this release, ensure that RTCM is disabled before using the data streams optimizer for the first time and remains disabled afterward. If you enable RTCM and then disable RTCM after the data streams optimizer has tuned the system, these problems may occur.
Solution: If system freeze is encountered, hard reset to regain control of the system. In some cases, flashing the BIOS will be required in order to apply a new capsule. In the case of detecting the error: “Could not set up firmware update: Invalid argument. ERROR: Failed to apply buffer capsule,” reboot to disable RTCM.
The data streams optimizer hangs after the “Rebooting <hostname>” output message during target reboot.
Cause: Most likely you have a “Broken pipe” issue in the case of an unexpected exit from the SSH session to the target system.
  • Fix the “Broken pipe” issue (may be SSH settings or network issue).
    1. Fix the connection issue by reviewing your IP addresses, connection settings, and cable connections.
    2. Review SSH settings.
  • Or change the reconnection timeout and reboot settings in the environment file:
    1. Increase
      to 70.
    2. Use
      shutdown -r 1
      instead of
After trying a solution, rerun the tuning flow from the beginning.
On 11th Gen Intel® Core™ processors, a system hang may occur intermittently when running the
Cause: If the system detects hardware errors, the Functional Safety (FuSa) feature, PCIe Interrupt Error Handling (IEH), may attempt an additional system reset which can get stuck at postcode 0x0b7f. Solution: Hard reset to regain control of the system.
Temporary resolution for system hang after reboot: Disable IEH in the BIOS menu: Intel Advanced Menu/PCH-IO Configuration/IEH Mode = Bypass Mode
For any other issue, run the command
to see whether any cores are offline. Example output: “Off-line CPU(s) list: 1-3.”
Cause: Combining RTCM and data streams optimizer may result in offline cores and a number of different errors. Solution: Reflash the BIOS.

Product and Performance Information


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