ARCHITECTURE_CHECKS.md

Spack Architecture-Specific Optimization Verification

This document explains how to verify that Spack is correctly configured for architecture-specific optimizations on this system.

Detected Architecture Information

• CPU Model: Intel(R) Xeon(R) CPU E5-2699 v3 @ 2.30GHz
• Architecture Target: x86_64
• Compiler Flags: -march=native -mtune=native -O3 -mavx2

Verification Commands

Run the following commands to verify the architecture-specific configuration:

1. Check the detected architecture

source /opt/spack/share/spack/setup-env.sh
spack arch

This shows the complete architecture specification Spack is using.

2. View available targets for your system

source /opt/spack/share/spack/setup-env.sh
spack arch --known-targets

This displays all microarchitecture targets Spack recognizes for your system.

3. Check compiler flags being used

source /opt/spack/share/spack/setup-env.sh
spack compiler info gcc

This shows the compiler configuration, including optimization flags.

4. Examine the Spack configuration files

cat /opt/spack/etc/spack/config.yaml
cat /opt/spack/etc/spack/packages.yaml
cat /opt/spack/etc/spack/compilers.yaml

These files show the architecture-specific settings that were applied.

5. Test a package installation with verbose output

source /opt/spack/share/spack/setup-env.sh
spack install --verbose openmpi

The verbose output shows the exact compiler flags used during compilation.

6. Check how a specific package would be built

source /opt/spack/share/spack/setup-env.sh
spack spec -I openmpi

This shows the complete specification for how OpenMPI would be built.

Interpreting Results

• The architecture should match your CPU (x86_64)
• Compiler flags should include architecture-specific optimizations (-march=native -mtune=native -O3 -mavx2)
• Package specs should show these optimizations are being applied