3.16

[3.16.0] - 2025-10-09

🎉 New Features

Tools API Environment Variable Support

• Automatic Lightweight Mode: Tools API now automatically detects and respects the DDS_LIGHTWEIGHT_PACKAGE environment variable
• No More make wn_bin: When using lightweight mode, you no longer need to build the worker binary package with make wn_bin - a huge time saver!
• Simplified API Usage: Users no longer need to manually set the enable_lightweight flag when the environment variable is set
• Consistent Behavior: Tools API now behaves consistently with command-line tools (dds-session and dds-submit)
• Smaller Packages: Worker packages reduced from ~15MB to ~50KB in lightweight mode

🐛 Bug Fixes

Critical SLURM Plugin Fix for Lightweight Mode

• Job Submission Failure: Fixed critical bug in SLURM plugin that caused job submissions to fail with "No partition specified or system default partition" error when using lightweight mode
• Root Cause: The job script template incorrectly placed executable validation code before #SBATCH directives, violating SLURM's parsing requirements. SLURM stops processing #SBATCH options when it encounters the first executable line, causing all subsequent directives (including --partition) to be ignored
• Template Bug: The placeholder #DDS_LIGHTWEIGHT_VALIDATION appeared in both a comment line and the code section. The boost::replace_all() function replaced both occurrences, breaking the comment syntax and injecting executable code before #SBATCH directives
• Resolution:
  • Removed lightweight validation code from the job script template entirely
  • Eliminated blank lines between #SBATCH directive placeholders
  • Validation logic moved to worker nodes where it's actually needed (DDSWorker.sh)
• Impact: SLURM now correctly parses all #SBATCH directives including partition specifications, resource requirements, and job options

Critical Worker Package Deployment Fix

• DDSWorker.sh Logic Error: Fixed inverted logic bug that caused worker package deployment to fail when pre-compiled binaries were present
• Impact: This bug prevented users from deploying full worker packages (with binaries) even though the binaries were correctly packaged
• Resolution: The script now correctly:
  • Extracts and uses binaries when they exist (full package mode)
  • Validates lightweight mode requirements when binaries are absent (lightweight package mode)

🚀 For Users

If You Use SLURM with Lightweight Mode

If you experienced SLURM job submission failures with errors like:

Batch job submission failed: No partition specified or system default partition

This was caused by a critical bug in the SLURM plugin template that placed executable code before #SBATCH directives. SLURM stopped parsing directives when it encountered this code, ignoring your partition specifications and other settings.

The fix requires rebuilding DDS:

cd /path/to/DDS/build
make
make install

After rebuilding, your SLURM submissions with lightweight mode will work correctly, and all #SBATCH directives (including partition, CPU requirements, etc.) will be properly recognized.

If You Use Tools API

Before this fix, you had to explicitly set the lightweight flag:

submitInfo.setFlag(SSubmitRequestData::ESubmitRequestFlags::enable_lightweight, true);

Now, simply set the environment variable before running your application:

export DDS_LIGHTWEIGHT_PACKAGE=1
./my_dds_app

The Tools API will automatically:

• Start sessions with --lightweight flag
• Configure submit requests for lightweight mode

If You Experienced Worker Package Failures

If you previously encountered errors like:

Error: Can't find WN pre-compiled bin.: /path/to/dds-wrk-bin-3.14-Linux-x86_64.tar.gz

This was caused by the DDSWorker.sh bug and is now fixed. Your worker packages will deploy correctly regardless of whether they contain pre-compiled binaries or are in lightweight mode.

📝 Complete Changelog

For a complete list of all changes, see CHANGELOG.md.

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