The Issue with Hardcoded Huge Page Size

Oct 13, 2025 by wbrum.org 7 views

Whitebox Tests Hardcode Huge Page Size as 2M, Causing Failures When System Huge Page Size Differs

When running TBB whitebox tests, some test cases hardcode the huge page size as 2MB. This can cause test assertions to fail if the system is configured with a non-2MB huge page size. In this article, we will explore the issue, its impact, and potential solutions.

Huge pages are a type of memory allocation that allows for larger memory blocks to be allocated at once. This can improve performance in certain applications by reducing the overhead of memory management. However, huge pages can also be configured to different sizes depending on the system and its requirements.

The Issue with Hardcoded Huge Page Size

The issue arises when some test cases in the TBB whitebox test suite hardcode the huge page size as 2MB. This hardcoded value is used in test assertions to verify the behavior of the memory allocation functions. However, if the system is configured with a non-2MB huge page size, the test assertions will fail.

Example Configuration and Error Message

In my environment, the configuration is set as follows:

Hugepagesize:       524288 kB
Hugetlb:               0 kB

This configuration sets the huge page size to 512MB. However, when running the TBB whitebox tests, I encountered the following error message:

/home/xxxxx/test/tbbmalloc/test_malloc_whitebox.cpp:xxx: FATAL ERROR: REQUIRE( allocSize == HUGE_PAGE_SIZE ) is NOT correct!
  values: REQUIRE( 536870912 == 2097152 )
  logged: Allocation size have to be aligned on Huge Page size internally.

This error message indicates that the test assertion failed because the allocation size (536870912) is not equal to the hardcoded huge page size (2097152).

Impact on CI/CD Pipelines and Cloud Environments

This issue may affect CI/CD pipelines or cloud environments where non-2MB huge pages are common. In such environments, the hardcoded huge page size in the TBB whitebox tests may cause test failures, leading to incorrect test results and potential issues with the deployment of the application.

Potential Solutions

To resolve this issue, the following solutions can be considered:

Update the Test Code: Update the test code to use a dynamic huge page size that can be configured based on the system settings. This will ensure that the test assertions are correct regardless of the system configuration.
Use a Configurable Huge Page Size: Introduce a configurable huge page size in the test code that can be set based on the system configuration. This will allow the test assertions to be correct regardless of the system configuration.
Add a System Configuration Check: Add a system configuration check to the test code to verify that the system is configured with a huge page size that matches the hardcoded value. If the system configuration does not match, the test can be skipped or modified to use a dynamic huge page size.

In conclusion, the hardcoded huge page size in some TBB whitebox test cases can cause test failures when the system is configured with a non-2MB huge page size. This issue may affect CI/CD pipelines or cloud environments where non-2MB huge pages are common. By updating the test code to use a dynamic huge page size or introducing a configurable huge page size, the issue can be resolved, and the test assertions can be correct regardless of the system configuration.
Whitebox Tests Hardcode Huge Page Size as 2M, Causing Failures When System Huge Page Size Differs: Q&A

In our previous article, we discussed the issue of hardcoded huge page size in some TBB whitebox test cases, which can cause test failures when the system is configured with a non-2MB huge page size. In this article, we will provide a Q&A section to address some common questions related to this issue.

Q: What is the impact of hardcoded huge page size on CI/CD pipelines and cloud environments?

A: The hardcoded huge page size in some TBB whitebox test cases can cause test failures in CI/CD pipelines and cloud environments where non-2MB huge pages are common. This can lead to incorrect test results and potential issues with the deployment of the application.

Q: How can I identify if my system is configured with a non-2MB huge page size?

A: You can identify if your system is configured with a non-2MB huge page size by checking the system configuration. You can use the following command to check the huge page size:

cat /proc/meminfo | grep Hugepagesize

This will display the huge page size in kilobytes.

Q: What are the potential solutions to resolve this issue?

A: There are several potential solutions to resolve this issue:

Update the Test Code: Update the test code to use a dynamic huge page size that can be configured based on the system settings.
Use a Configurable Huge Page Size: Introduce a configurable huge page size in the test code that can be set based on the system configuration.
Add a System Configuration Check: Add a system configuration check to the test code to verify that the system is configured with a huge page size that matches the hardcoded value. If the system configuration does not match, the test can be skipped or modified to use a dynamic huge page size.

Q: How can I update the test code to use a dynamic huge page size?

A: To update the test code to use a dynamic huge page size, you can use the following approach:

Get the System Huge Page Size: Get the system huge page size using the cat /proc/meminfo | grep Hugepagesize command.
Update the Test Code: Update the test code to use the system huge page size instead of the hardcoded value.
Verify the Test Results: Verify that the test results are correct after updating the test code.

Q: What are the benefits of using a configurable huge page size?

A: Using a configurable huge page size has several benefits, including:

Improved Test Flexibility: A configurable huge page size allows the test code to be flexible and adaptable to different system configurations.
Reduced Test Failures: A configurable huge page size can reduce test failures caused by hardcoded huge page sizes.
Improved Test Reliability: A configurable huge page size can improve test reliability by ensuring that the test code is correct and accurate.

In conclusion, the hardcoded huge page size in some TBB whitebox test cases can cause test failures when the system is configured with a non-2MB huge page size. By updating the test code to use a dynamic huge page size or introducing a configurable huge page size, the issue can be resolved, and the test assertions can be correct regardless of the system configuration.