Fix Nix download buffer warning during Docker/Nix builds #9
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Co-authored-by: copilot-swe-agent[bot] <[email protected]> Co-authored-by: mrinalwadhwa <[email protected]>
Co-authored-by: mrinalwadhwa <[email protected]>
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[WIP] fix warning during the docker / nix build
Fix Nix download buffer warning during Docker/Nix builds
Aug 4, 2025
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August 4, 2025 17:17
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This PR resolves the warning that appears during Docker and Nix builds:
The warning occurs when Nix downloads large packages or many packages simultaneously and the default download buffer (64MB) becomes insufficient. This is a common issue in containerized environments where multiple large dependencies are downloaded during the build process.
Changes Made
Added
download-buffer-size = 268435456(256MB) to the Nix configuration in three locations:.devcontainer/Dockerfile- Development container configurationtools/docker/dev/Dockerfile- Docker development environment.github/actions/setup_nix/action.yaml- GitHub Actions CI setupThe setting increases the download buffer from the default 64MB to 256MB, providing 4x more capacity for handling concurrent downloads without triggering the buffer overflow warning.
Technical Implementation
The fix follows Nix's recommended approach by adding the buffer size setting to
/etc/nix/nix.conf:This configuration is applied consistently across all environments where Nix is used in the repository, ensuring the warning is eliminated regardless of the build context (local development, CI/CD, or containerized environments).
The 256MB buffer size strikes a balance between providing sufficient capacity for most download scenarios while avoiding excessive memory consumption on resource-constrained systems.
Fixes #8.
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