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@Copilot Copilot AI commented Aug 4, 2025

This PR resolves the warning that appears during Docker and Nix builds:

warning: download buffer is full; consider increasing the 'download-buffer-size' setting

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:

  1. .devcontainer/Dockerfile - Development container configuration
  2. tools/docker/dev/Dockerfile - Docker development environment
  3. .github/actions/setup_nix/action.yaml - GitHub Actions CI setup

The 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:

echo "download-buffer-size = 268435456" >> /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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@Copilot Copilot AI changed the title [WIP] fix warning during the docker / nix build Fix Nix download buffer warning during Docker/Nix builds Aug 4, 2025
Copilot finished work on behalf of mrinalwadhwa August 4, 2025 17:17
@Copilot Copilot AI requested a review from mrinalwadhwa August 4, 2025 17:17
@mrinalwadhwa mrinalwadhwa force-pushed the main branch 5 times, most recently from 6b38ec1 to 09dc4a7 Compare August 4, 2025 18:48
@mrinalwadhwa mrinalwadhwa force-pushed the main branch 8 times, most recently from a8ac5f3 to 722aef6 Compare September 9, 2025 21:32
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fix warning during the docker / nix build
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