[23654] Change non_blocking_send threshold to sendBufferSize

[juanlofer-eprosima]

Description

Currently the non blocking size feature assumes that the size of TCP sockets allocated by the OS is twice the value requested (sendBufferSize). However, it has been observed that the actual reserved value may fall below that value, hence blocking when the buffer gets full and ruining the purpose of this feature.

@Mergifyio backport 3.3.x 3.2.x 2.14.x

Contributor Checklist

• Commit messages follow the project guidelines.
• The code follows the style guidelines of this project.
• Tests that thoroughly check the new feature have been added/Regression tests checking the bug and its fix have been added; the added tests pass locally
• N/a Any new/modified methods have been properly documented using Doxygen.
• N/a Any new configuration API has an equivalent XML API (with the corresponding XSD extension)
• Changes are backport compatible: they do NOT break ABI nor change library core behavior.
• Changes are API compatible.
• N/a New feature has been added to the versions.md file (if applicable).
• N/a New feature has been documented/Current behavior is correctly described in the documentation.
• Applicable backports have been included in the description.

Reviewer Checklist

• The PR has a milestone assigned.
• The title and description correctly express the PR's purpose.
• Check contributor checklist is correct.
• If this is a critical bug fix, backports to the critical-only supported branches have been requested.
• Check CI results: changes do not issue any warning.
• Check CI results: failing tests are unrelated with the changes.

[mergify]

🧪 CI Insights

Here's what we observed from your CI run for 8f86a2f.

❌ Job Failures

Pipeline	Job	Health on master	Retries	🔍 CI Insights	📄 Logs
Fast DDS MacOS CI	mac-ci / fastdds_test ()		0	View	View

✅ Passed Jobs With Interesting Signals

Pipeline	Job	Signal	Health on master	Retries	🔍 CI Insights	📄 Logs
Fast DDS Ubuntu CI	ubuntu-ci / fastdds_build (RelWithDebInfo)	Base branch is broken, but the job passed. Looks like this might be a real fix 💪		0	View	View

[cferreiragonz]

LGTM, although it really surprises me that ubuntu-ci failed twice. I am re-running it just in case

[cferreiragonz]

Let's assume failed tests in previous runs were unrelated. I was not able to reproduce them locally

[juanlofer-eprosima]

https://github.com/Mergifyio backport 3.3.x 3.2.x 2.14.x

[mergify]

backport 3.3.x 3.2.x 2.14.x

✅ Backports have been created

Details

• #6077 [23654] Change non_blocking_send threshold to sendBufferSize (backport #6073) has been created for branch 3.3.x
• #6078 [23654] Change non_blocking_send threshold to sendBufferSize (backport #6073) has been created for branch 3.2.x
• #6079 [23654] Change non_blocking_send threshold to sendBufferSize (backport #6073) has been created for branch 2.14.x but encountered conflicts