Created a benchmarks file

.github/workflows/benchmark.yml

@@ -0,0 +1,118 @@
+name: Benchmark
+
+on:
+  workflow_dispatch:
+    inputs:
+      baseline_ref:
+        description: "Branch/tag/commit to compare against"
+        required: false
+        default: "main"
+  pull_request:
+    types: [opened, synchronize, reopened, labeled]
+
+permissions:
+  contents: read
+
+jobs:
+  benchmark:
+    if: github.event_name == 'workflow_dispatch' || contains(github.event.pull_request.labels.*.name, 'run-benchmarks')
+    runs-on: ubuntu-latest
+    env:
+      BASE_REF: ${{ github.event_name == 'workflow_dispatch' && inputs.baseline_ref || github.base_ref }}
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Set up Julia
+        uses: julia-actions/setup-julia@v2
+        with:
+          version: "1"
+
+      - name: Cache Julia artifacts
+        uses: julia-actions/cache@v2
+
+      - name: Ensure baseline ref is available
+        run: git fetch origin "${BASE_REF}" --depth=1
+
+      - name: Instantiate benchmark environment
+        run: julia --project=benchmark -e 'using Pkg; Pkg.instantiate(); Pkg.develop(PackageSpec(path=pwd())); Pkg.instantiate()'
+
+      - name: Compare benchmarks against baseline
+        run: |
+          if git cat-file -e "origin/${BASE_REF}:benchmark/Project.toml" 2>/dev/null; then
+            julia --project=benchmark -e '
+              using PkgBenchmark
+              baseline = "origin/$(ENV["BASE_REF"])"
+              judgment = judge(pwd(), "HEAD", baseline)
+              mkpath("benchmark-results")
+              export_markdown("benchmark-results/report.md", judgment; export_invariants=true)
+              '
+            touch benchmark-results/has_judgment
+          else
+            julia --project=benchmark -e '
+              using BenchmarkTools
+              include("benchmark/benchmarks.jl")
+              results = run(SUITE; seconds=1)
+              mkpath("benchmark-results")
+              open("benchmark-results/report.md", "w") do io
+                  println(io, "# Benchmark Report")
+                  println(io)
+                  println(io, "Baseline branch `$(ENV["BASE_REF"])` does not contain `benchmark/Project.toml`.")
+                  println(io, "Ran current-branch benchmarks only; regression comparison skipped.")
+                  println(io)
+                  show(io, MIME"text/plain"(), results)
+                  println(io)
+              end
+              '
+            touch benchmark-results/no_judgment
+          fi
+
+      - name: Print benchmark report in job log
+        run: |
+          echo "=== Benchmark Report ==="
+          cat benchmark-results/report.md
+
+      - name: Publish benchmark report in step summary
+        run: |
+          cat benchmark-results/report.md >> "${GITHUB_STEP_SUMMARY}"
+
+      - name: Fail on regression above 15%
+        run: |
+          if [ -f benchmark-results/no_judgment ]; then
+            echo "No baseline benchmark harness found; skipping regression gate."
+            exit 0
+          fi
+          julia --project=benchmark -e '
+            threshold = 15.0
+            report = read("benchmark-results/report.md", String)
+            worst = 0.0
+            offenders = String[]
+            for line in split(report, "\n")
+                m = match(r"\+([0-9]+(?:\.[0-9]+)?)%", line)
+                m === nothing && continue
+                pct = parse(Float64, m.captures[1])
+                worst = max(worst, pct)
+                if pct > threshold
+                    push!(offenders, strip(line))
+                end
+            end
+
+            println("Maximum parsed regression: ", round(worst; digits=2), "%")
+            if isempty(offenders)
+                println("No regression above ", threshold, "% detected.")
+                exit(0)
+            end
+
+            println("Regressions above ", threshold, "%:")
+            foreach(x -> println("  ", x), offenders)
+            exit(1)
+            '
+
+      - name: Upload benchmark report
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: benchmark-report
+          path: benchmark-results/report.md

Project.toml

@@ -8,12 +8,20 @@ LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 Printf = "de0858da-6303-5e67-8744-51eddeeeb8d7"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 StructArrays = "09ab397b-f2b6-538f-b94a-2f83cf4a842a"
-Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [compat]
 julia = "1.8 - 1"
 StaticArrays = "1.9 - 1"
 StructArrays = "0.7.1 - 0.7"
 LinearAlgebra = "1"
 Printf = "1"
-Test = "1"
+Test = "1"
+BenchmarkTools = "1"
+
+[extras]
+BenchmarkTools = "6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf"
+Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+
+[targets]
+benchmark = ["BenchmarkTools"]
+test = ["Test"]

benchmark/Project.toml

@@ -0,0 +1,9 @@
+[deps]
+BenchmarkTools = "6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf"
+IdealGasThermo = "d4fb33c0-2494-4384-b7a5-e5d0487b6649"
+PkgBenchmark = "32113eaa-f34f-5b0d-bd6c-c81e245fc73d"
+
+[compat]
+BenchmarkTools = "1"
+PkgBenchmark = "0.2"
+julia = "1.8 - 1"

benchmark/benchmarks.jl

@@ -0,0 +1,34 @@
+using BenchmarkTools
+using IdealGasThermo
+
+const SUITE = BenchmarkGroup()
+
+const TT = rand(200.0:600.0, 100)
+
+function benchmark_gas!(TT::AbstractVector, gas::IdealGasThermo.AbstractGas)
+    @views for i in eachindex(TT)
+        gas.T = TT[i]
+        gas.cp
+        gas.ϕ
+        gas.h
+        gas.cp_T
+    end
+    return nothing
+end
+
+function benchmark_enthalpy()
+    gas = Gas()
+    gas.h = 1e5
+    return gas
+end
+
+function benchmark_combustion()
+    gas_ox = Gas()
+    fuel = "CH4"
+    return IdealGasThermo.fuel_combustion(gas_ox, fuel, 298.15, 1e-2)
+end
+
+SUITE["gas"]["Gas1D thermo properties"] = @benchmarkable benchmark_gas!($TT, $(Gas1D()))
+SUITE["gas"]["Gas thermo properties"] = @benchmarkable benchmark_gas!($TT, $(Gas()))
+SUITE["state"]["Set enthalpy"] = @benchmarkable benchmark_enthalpy()
+SUITE["combustion"]["fuel_combustion"] = @benchmarkable benchmark_combustion()