Overview

This project builds a custom MongoDB 8.0.* server package for Ubuntu 22.04 (Jammy) or Ubuntu 24.04 (Noble) with specific patches and configuration adjustments.

It applies patches from the patches/ directory to build MongoDB without AVX compiler flags, enabling compatibility with older CPUs that do not support AVX or AVX2 instructions.

The build uses --copt=-march=${CPU_ARCH} (for example nehalem or core2) so you can target older machines. Core 2–class CPUs lack SSE4.2 as well as AVX/AVX2; when CPU_ARCH=core2, an extra Snappy patch is applied (see below).

This project is based on the official MongoDB source code, which is licensed under the Server Side Public License (SSPL) v1.
The original source code is available here:
https://github.com/mongodb/mongo

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Patches

The following patches are applied to the MongoDB source tree:

• 0001-Compile-without-debug-symbols.patch
  Removes debug symbols to reduce binary size.

• 0002-Removed_AVX-2_CCFLAG_from_mozjs.patch
  Eliminates AVX2-specific compile flags from the mozjs library.

• 0003-Disabled_AVX_in_mozjs_SIMD.patch
  Disables AVX instruction use inside mozjs SIMD implementation.

• 0004-Disable-advanced-features-gcc.patch Improves compatibility and portability by avoiding advanced CPU-specific features.

For core2 (--build-arg CPU_ARCH=core2)

• core2/0005-disable-crc32-snappy.patch
  Disables the x86 CRC32 fast path in Snappy (uses a portable hash instead), avoiding SSE4.2 crc32 instructions that Core 2 does not support.

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Dockerfiles

Use one of the following to build the mongod binary inside a matching Ubuntu image:

• Dockerfile-jammy – Ubuntu 22.04 (Jammy)
• Dockerfile-noble – Ubuntu 24.04 (Noble; Bazel adds GCC 13 workarounds: -Wno-interference-size, -Wno-mismatched-new-delete, -Wno-array-bounds, -Wno-stringop-overflow)

The Dockerfile includes build dependencies and scripts to produce a custom mongod file.

Noble vs Jammy compiler: Noble’s default GCC 13 is stricter than Jammy’s GCC 11 for diagnostics that MongoDB 8.0.x triggers under -Werror. APT packages here are normal LTS compilers, not outdated. Extra --cxxopt/--copt on Noble work around GCC-13-specific issues (immer, std::hardware_*_interference_size, etc.). In .bazelrc.local this repo uses --cxxopt=-Wno-pessimizing-move instead of -Wpessimizing-move so redundant std::move diagnostics are not enabled on top of Mongo’s warning set.

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Build Instructions

To build the Docker image and generate a custom mongod file, run:

./builder.sh [<REVISION>] [<CPU_ARCH>] [<UBUNTU_CODENAME>]

Example:

./builder.sh "12" "nehalem"
./builder.sh "12" "core2"

CPU_ARCH is any valid GCC -march= value (default in Dockerfile: nehalem). For Core 2, use core2 so the Dockerfile merges in the Snappy CRC32 patch.

Examples (Noble)

./builder.sh "12" "nehalem" noble
./builder.sh "12" "core2" noble