chore(benchmark): change benchmark worflow to run weekly instead of PRs

.github/workflows/benchmark.yml

@@ -1,15 +1,27 @@
 name: Benchmark
 on:
-  push:
-    branches: [ "main", "master" ]
-  pull_request:
-    branches: [ "main", "master" ]
+  # Runs only on demand or on a schedule so CI minutes aren't burned on every push.
+  schedule:
+    - cron: "0 3 * * 1" # weekly (Mon 03:00 UTC)
   workflow_dispatch:
+    inputs:
+      benchtime:
+        description: Duration per benchmark (go -benchtime)
+        required: false
+        default: "1s"
+      count:
+        description: Number of runs per benchmark (go -count); median of runs is reported
+        required: false
+        default: "3"
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
 
+env:
+  BENCHTIME: ${{ inputs.benchtime || '1s' }}
+  BENCH_COUNT: ${{ inputs.count || '3' }}
+
 jobs:
   benchmark:
     name: Benchmark (${{ matrix.db }})
@@ -66,7 +78,6 @@ jobs:
   save-benchmarks:
     name: Save Benchmark JSON
     needs: benchmark
-    if: ${{ github.event_name != 'pull_request' }}
     runs-on: ubuntu-latest
     permissions:
       contents: write
@@ -94,7 +105,7 @@ jobs:
             git config user.name "github-actions[bot]"
             git config user.email "github-actions[bot]@users.noreply.github.com"
             git add benchmark/benchmarks.json
-            git commit -m "chore(benchmark): update benchmark/benchmarks.json [skip ci]"
+            git commit -m "chore(benchmark): update benchmark results [skip ci]"
             git push
           else
             echo "No benchmark results changed."

benchmark/benchmark_test.go

@@ -2,11 +2,14 @@ package main
 
 import (
 	"fmt"
+	"math/rand"
 	"testing"
 )
 
+// Mirrors the shuffle technique used by github.com/efectn/go-orm-benchmarks.
 func orms(b *testing.B, fns map[string]func(*testing.B)) {
 	order := []string{"Raw", "Phi", "Bun", "Ent", "GORM"}
+	rand.Shuffle(len(order), func(i, j int) { order[i], order[j] = order[j], order[i] })
 	for _, name := range order {
 		if fn, ok := fns[name]; ok {
 			b.Run(name, fn)