From b0568fc2e04d2881cff1d9eb9d47fdde51244911 Mon Sep 17 00:00:00 2001
From: Shigoto-dev19 <shigoto-dev19@protonmail.com>
Date: Tue, 14 Oct 2025 11:13:17 +0300
Subject: [PATCH 1/7] Add performance regression tests to CI

---
 .../actions/upload-perf-baseline/action.yml   | 35 +++++++++++++++++++
 .github/workflows/checks.yml                  | 12 +++++++
 run-ci-tests.sh                               |  6 ++++
 3 files changed, 53 insertions(+)
 create mode 100644 .github/actions/upload-perf-baseline/action.yml

diff --git a/.github/actions/upload-perf-baseline/action.yml b/.github/actions/upload-perf-baseline/action.yml
new file mode 100644
index 0000000000..59fab5ca26
--- /dev/null
+++ b/.github/actions/upload-perf-baseline/action.yml
@@ -0,0 +1,35 @@
+name: Upload Perf Baseline (optional)
+description: Upload perf-regression.json only when PERF_MODE is --dump.
+inputs:
+  perf_mode:
+    description: "--dump or --check"
+    required: true
+  path:
+    description: "Path to perf baseline JSON"
+    required: false
+    default: tests/perf-regression/perf-regression.json
+  name:
+    description: "Artifact name"
+    required: false
+    default: perf-regression-json
+  retention-days:
+    description: "Artifact retention (days)"
+    required: false
+    default: "30"
+
+runs:
+  using: "composite"
+  steps:
+    - name: Skip unless in dump mode
+      if: inputs.perf_mode != '--dump'
+      shell: bash
+      run: echo "Not in --dump mode; skipping upload."
+
+    - name: Upload baseline
+      if: inputs.perf_mode == '--dump'
+      uses: actions/upload-artifact@v4
+      with:
+        name: ${{ inputs.name }}
+        path: ${{ inputs.path }}
+        if-no-files-found: error
+        retention-days: ${{ inputs.retention-days }}
diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index 546dc719c0..eaa4bfbe03 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -152,6 +152,7 @@ jobs:
             'Verification Key Regression Check 2',
             'CommonJS test',
             'Cache Regression',
+            'Performance Regression',
           ]
     steps:
       - name: Checkout repository with submodules
@@ -176,7 +177,18 @@ jobs:
       - name: Execute tests
         env:
           TEST_TYPE: ${{ matrix.test_type }}
+          PERF_MODE: ${{ contains(github.event.pull_request.labels.*.name, 'dump-performance') && '--dump' || '--check' }}
         run: sh run-ci-tests.sh
+      - name: Upload performance regressions baseline
+        if: >
+          matrix.test_type == 'Performance Regression' &&
+          contains(github.event.pull_request.labels.*.name, 'dump-performance')
+        uses: ./.github/actions/upload-perf-baseline
+        with:
+          perf_mode: ${{ contains(github.event.pull_request.labels.*.name, 'dump-performance') && '--dump' || '--check' }}
+          path: tests/perf-regression/perf-regression.json
+          name: perf-regression-json
+          retention-days: 30
       - name: Add to job summary
         if: always()
         run: |
diff --git a/run-ci-tests.sh b/run-ci-tests.sh
index 213514dc0c..dbc1ee71d3 100755
--- a/run-ci-tests.sh
+++ b/run-ci-tests.sh
@@ -53,6 +53,12 @@ case $TEST_TYPE in
   echo "Cache Regression"
   ./scripts/tests/check-cache-regressions.sh
   ;;
+  
+"Performance Regression")
+  echo "Running Performance Regression Check"
+  PERF_MODE="${PERF_MODE:---check}"
+  ./tests/perf-regression/perf-regression.sh "$PERF_MODE"
+  ;;
 *)
   echo "ERROR: Invalid environment variable, not clear what tests to run! $CI_NODE_INDEX"
   exit 1

From e512d764dac78c9db348ef9b8bcd390acf394a94 Mon Sep 17 00:00:00 2001
From: Shigoto-dev19 <shigoto-dev19@protonmail.com>
Date: Tue, 14 Oct 2025 19:12:10 +0300
Subject: [PATCH 2/7] Fix performance regression check in CI by downloading the
 baseline

---
 .github/workflows/checks.yml | 76 ++++++++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)

diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index eaa4bfbe03..c68cc40739 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -33,6 +33,7 @@ concurrency:
 
 permissions:
   contents: write
+  actions: read
 
 jobs:
   Prepare:
@@ -174,6 +175,81 @@ jobs:
           credentials_json: '${{ secrets.GCP_O1JS_CI_BUCKET_SERVICE_ACCOUNT_KEY }}'
       - name: Prepare for tests
         run: touch profiling.md
+      - name: Find a prior run that actually has perf baseline
+        id: find-baseline
+        if: >
+          matrix.test_type == 'Performance Regression' && !contains(github.event.pull_request.labels.*.name, 'dump-performance')
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          TARGET_REPO: ${{ inputs.target_repo || github.repository }}
+          WORKFLOW_NAME: ${{ github.workflow }}   # display name, e.g. "Checks"
+          BRANCH: ${{ github.head_ref || github.ref_name }}
+          ARTIFACT_NAME: perf-regression-json
+        run: |
+          set -euo pipefail
+
+          echo "Looking for completed prior runs of '$WORKFLOW_NAME' on '$BRANCH' in $TARGET_REPO with artifact '$ARTIFACT_NAME'"
+
+          # List recent COMPLETED runs (don't require 'success' to survive matrix failures)
+          RUN_IDS=$(gh run list \
+            --repo "$TARGET_REPO" \
+            --workflow "$WORKFLOW_NAME" \
+            --json databaseId,headBranch,status,conclusion \
+            --limit 40 \
+            --jq "[.[] | select(.status==\"completed\" and .headBranch==\"$BRANCH\") | .databaseId] | .[]" \
+            || true)
+
+          if [[ -z "${RUN_IDS:-}" ]]; then
+            echo "No completed runs found on this branch in $TARGET_REPO."
+            echo "Seed a baseline once (add 'dump-performance' label) or relax branch to 'main' later."
+            exit 1
+          fi
+
+          # Pick the first run that actually has the artifact and it's not expired
+          FOUND=""
+          for RID in $RUN_IDS; do
+            HAS=$(gh api repos/"$TARGET_REPO"/actions/runs/"$RID"/artifacts \
+              --jq ".artifacts | map(select(.name==\"$ARTIFACT_NAME\" and .expired==false)) | length")
+            echo "Run $RID has $HAS matching artifact(s)."
+            if [[ "$HAS" -gt 0 ]]; then
+              FOUND="$RID"
+              break
+            fi
+          done
+
+          if [[ -z "${FOUND:-}" ]]; then
+            echo "No prior completed run on '$BRANCH' has artifact '$ARTIFACT_NAME'."
+            echo "Seed a baseline once (add 'dump-performance' label) so check mode can download it."
+            exit 1
+          fi
+
+          echo "run_id=$FOUND" >> "$GITHUB_OUTPUT"
+          echo "Found suitable run id: $FOUND"
+      - name: Download baseline artifact from that run
+        if: >
+          matrix.test_type == 'Performance Regression' && !contains(github.event.pull_request.labels.*.name, 'dump-performance')
+        uses: actions/download-artifact@v4
+        with:
+          name: perf-regression-json
+          run-id: ${{ steps.find-baseline.outputs.run_id }}
+          path: tests/perf-regression
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Normalize baseline path for the script
+        if: >
+          matrix.test_type == 'Performance Regression' &&!contains(github.event.pull_request.labels.*.name, 'dump-performance')
+        run: |
+          set -euo pipefail 
+          FILE="$(find tests/perf-regression -name 'perf-regression.json' -print -quit || true)"
+          if [[ -z "${FILE:-}" ]]; then
+            echo "ERROR: perf-regression.json not found inside downloaded artifact."
+            echo "Listing:"
+            ls -R tests/perf-regression || true
+            exit 1
+          fi
+          if [[ "$FILE" != "tests/perf-regression/perf-regression.json" ]]; then
+            mv -f "$FILE" tests/perf-regression/perf-regression.json
+          fi
+          echo "Baseline ready at tests/perf-regression/perf-regression.json"
       - name: Execute tests
         env:
           TEST_TYPE: ${{ matrix.test_type }}

From 55e2072bd3256cac14acf65fa641fa43b7f8dcd8 Mon Sep 17 00:00:00 2001
From: Shigoto-dev19 <shigoto-dev19@protonmail.com>
Date: Wed, 15 Oct 2025 13:23:06 +0300
Subject: [PATCH 3/7] Prettify logs for zkprograms performance regression check

---
 src/lib/testing/perf-regression.ts | 75 +++++++++++++++++++++++++-----
 1 file changed, 64 insertions(+), 11 deletions(-)

diff --git a/src/lib/testing/perf-regression.ts b/src/lib/testing/perf-regression.ts
index cd754ef085..86bf415eef 100644
--- a/src/lib/testing/perf-regression.ts
+++ b/src/lib/testing/perf-regression.ts
@@ -26,7 +26,7 @@ import minimist from 'minimist';
 import path from 'path';
 import { ConstraintSystemSummary } from '../provable/core/provable-context.js';
 
-export { PerfRegressionEntry, Performance };
+export { PerfRegressionEntry, Performance, logPerf };
 
 type MethodsInfo = Record<
   string,
@@ -358,10 +358,12 @@ function checkAgainstBaseline(params: {
 
   // tolerances
   const compileTol = 1.05; // 5%
-  const compileTiny = 1.08; // for near-zero baselines
+  const compileTiny = 1.08; // for near-zero baselines (< 5e-5s)
   const timeTolDefault = 1.1; // 10% for prove/verify
   const timeTolSmall = 1.25; // 25% for very small times (<0.2s)
 
+  const labelPretty = label[0].toUpperCase() + label.slice(1);
+
   if (label === 'compile') {
     const expected = baseline.compileTime;
     if (expected == null) {
@@ -369,15 +371,21 @@ function checkAgainstBaseline(params: {
         `No baseline compileTime for "${programName}". Run --dump (compile) to set it.`
       );
     }
+
     const tol = expected < 5e-5 ? compileTiny : compileTol;
     const allowedPct = (tol - 1) * 100;
+    const regressionPct = expected === 0 ? 0 : ((actualTime - expected) / expected) * 100;
+    const failed = actualTime > expected * tol;
 
-    if (actualTime > expected * tol) {
-      const regressionPct = ((actualTime - expected) / expected) * 100;
+    // colorized perf log
+    logPerf(programName, label, expected, actualTime, regressionPct, allowedPct, failed);
+
+    if (failed) {
       throw new Error(
         `Compile regression for ${programName}\n` +
-          `  Actual:   ${actualTime.toFixed(6)}s\n` +
-          `  Regression: +${regressionPct.toFixed(2)}% (allowed +${allowedPct.toFixed(0)}%)`
+          `  Actual:     ${actualTime.toFixed(6)}s\n` +
+          `  Baseline:   ${expected.toFixed(6)}s\n` +
+          `  Regression: +${Number.isFinite(regressionPct) ? regressionPct.toFixed(2) : '∞'}% (allowed +${allowedPct.toFixed(0)}%)`
       );
     }
     return;
@@ -390,6 +398,7 @@ function checkAgainstBaseline(params: {
       `No baseline method entry for ${programName}.${methodName}. Run --dump (${label}) to add it.`
     );
   }
+
   if (baseMethod.digest !== digest) {
     throw new Error(
       `Digest mismatch for ${programName}.${methodName}\n` +
@@ -399,21 +408,65 @@ function checkAgainstBaseline(params: {
   }
 
   const expected = label === 'prove' ? baseMethod.proveTime : baseMethod.verifyTime;
-  const labelPretty = label.charAt(0).toUpperCase();
   if (expected == null) {
     throw new Error(
       `No baseline ${label}Time for ${programName}.${methodName}. Run --dump (${label}) to set it.`
     );
   }
+
   const tol = expected < 0.2 ? timeTolSmall : timeTolDefault;
   const allowedPct = (tol - 1) * 100;
+  const regressionPct = expected === 0 ? 0 : ((actualTime - expected) / expected) * 100;
+  const failed = actualTime > expected * tol;
+
+  logPerf(
+    `${programName}.${methodName}`,
+    label,
+    expected,
+    actualTime,
+    regressionPct,
+    allowedPct,
+    failed
+  );
 
-  if (actualTime > expected * tol) {
-    const regressionPct = ((actualTime - expected) / expected) * 100;
+  if (failed) {
     throw new Error(
       `${labelPretty} regression for ${programName}.${methodName}\n` +
-        `  Actual:   ${actualTime.toFixed(3)}s\n` +
-        `  Regression: +${regressionPct.toFixed(2)}% (allowed +${allowedPct.toFixed(0)}%)`
+        `  Actual:     ${actualTime.toFixed(3)}s\n` +
+        `  Baseline:   ${expected.toFixed(3)}s\n` +
+        `  Regression: +${Number.isFinite(regressionPct) ? regressionPct.toFixed(2) : '∞'}% (allowed +${allowedPct.toFixed(0)}%)`
     );
   }
 }
+
+function logPerf(
+  scope: string,
+  label: string,
+  expected: number,
+  actual: number,
+  regressionPct: number,
+  allowedPct: number,
+  failed: boolean
+) {
+  const COLORS = {
+    reset: '\x1b[0m',
+    red: '\x1b[31m',
+    green: '\x1b[32m',
+    yellow: '\x1b[33m',
+    cyan: '\x1b[36m',
+  };
+
+  let color: string;
+  if (failed) color = COLORS.red;
+  else if (regressionPct > 0) color = COLORS.yellow;
+  else color = COLORS.green;
+
+  console.log(
+    `${COLORS.cyan}[Perf][${scope}]${COLORS.reset} ${label}: ` +
+      `baseline=${expected.toFixed(6)}s, actual=${actual.toFixed(6)}s, ` +
+      `${color}regression=${regressionPct >= 0 ? '+' : ''}${
+        Number.isFinite(regressionPct) ? regressionPct.toFixed(2) : '∞'
+      }%${COLORS.reset} ` +
+      `(allowed +${allowedPct.toFixed(0)}%)`
+  );
+}

From 08b2fb12aba6550144f1a32c7a73f3ea61971b9b Mon Sep 17 00:00:00 2001
From: Shigoto-dev19 <shigoto-dev19@protonmail.com>
Date: Wed, 15 Oct 2025 13:23:53 +0300
Subject: [PATCH 4/7] Prettify logs and adjust tolerances for zkApp and CS
 performance regression checks

---
 tests/perf-regression/perf-regression.ts | 35 ++++++++++++++++++++----
 1 file changed, 29 insertions(+), 6 deletions(-)

diff --git a/tests/perf-regression/perf-regression.ts b/tests/perf-regression/perf-regression.ts
index 171f050ac7..3f445657f9 100644
--- a/tests/perf-regression/perf-regression.ts
+++ b/tests/perf-regression/perf-regression.ts
@@ -20,7 +20,7 @@ import { TokenContract, createDex } from '../../src/examples/zkapps/dex/dex.js';
 import { HelloWorld } from '../../src/examples/zkapps/hello-world/hello-world.js';
 import { Membership_ } from '../../src/examples/zkapps/voting/membership.js';
 import { Voting_ } from '../../src/examples/zkapps/voting/voting.js';
-import { PerfRegressionEntry } from '../../src/lib/testing/perf-regression.js';
+import { PerfRegressionEntry, logPerf } from '../../src/lib/testing/perf-regression.js';
 import { tic, toc } from '../../src/lib/util/tic-toc.js';
 import {
   BasicCS,
@@ -118,14 +118,37 @@ async function checkPerf(contracts: MinimumConstraintSystem[]) {
       continue;
     }
 
-    const tolerance = expectedCompile < 5e-5 ? 1.08 : 1.05;
-    const allowedPct = (tolerance - 1) * 100;
+    // Tiered tolerances:
+    // < 0.00001s → 45%
+    // 0.00001s ≤ t < 0.0001s → 30%
+    // ≥ 0.0001s → 20%
+    let allowedPct: number;
+    if (expectedCompile < 1e-5) {
+      allowedPct = 45;
+    } else if (expectedCompile < 1e-4) {
+      allowedPct = 30;
+    } else {
+      allowedPct = 20;
+    }
+    const tolerance = 1 + allowedPct / 100;
+
+    const regressionPct =
+      expectedCompile === 0
+        ? compileTime === 0
+          ? 0
+          : Infinity
+        : ((compileTime - expectedCompile) / expectedCompile) * 100;
+
+    // colorized log using imported utility
+    const failed = compileTime > expectedCompile * tolerance;
+    logPerf(c.name, 'compile', expectedCompile, compileTime, regressionPct, allowedPct, failed);
 
-    if (compileTime > expectedCompile * tolerance) {
-      const regressionPct = ((compileTime - expectedCompile) / expectedCompile) * 100;
+    // handle failure
+    if (failed) {
       errorStack += `\n\nCompile regression for ${c.name}
   Actual:     ${compileTime.toFixed(6)}s
-  Regression: +${regressionPct.toFixed(2)}% (allowed +${allowedPct.toFixed(0)}%)`;
+  Baseline:   ${expectedCompile.toFixed(6)}s
+  Regression: +${Number.isFinite(regressionPct) ? regressionPct.toFixed(2) : '∞'}% (allowed +${allowedPct.toFixed(0)}%)`;
     }
   }
 

From 4702ace6b0e4b834f33bf130cbdd9c0884947cf0 Mon Sep 17 00:00:00 2001
From: Shigoto-dev19 <shigoto-dev19@protonmail.com>
Date: Wed, 15 Oct 2025 14:06:36 +0300
Subject: [PATCH 5/7] Refactor performance regression CI tests into unified
 composite action

---
 .github/actions/perf-regression/action.yml    | 199 ++++++++++++++++++
 .../actions/upload-perf-baseline/action.yml   |  35 ---
 .github/workflows/checks.yml                  | 100 ++-------
 3 files changed, 214 insertions(+), 120 deletions(-)
 create mode 100644 .github/actions/perf-regression/action.yml
 delete mode 100644 .github/actions/upload-perf-baseline/action.yml

diff --git a/.github/actions/perf-regression/action.yml b/.github/actions/perf-regression/action.yml
new file mode 100644
index 0000000000..23e0f7b95e
--- /dev/null
+++ b/.github/actions/perf-regression/action.yml
@@ -0,0 +1,199 @@
+name: Perf Regression (dump/check)
+description: Dump or check perf baseline; auto mode via label; find/download prior baseline; run tests; upload on dump.
+
+inputs:
+  mode:
+    description: "'dump' | 'check' | 'auto' (auto uses live PR labels)"
+    required: false
+    default: auto
+  label_name:
+    description: "Label that triggers dump when present (auto mode)"
+    required: false
+    default: dump-performance
+
+  artifact_name:
+    description: "Artifact name used to store the baseline"
+    required: false
+    default: perf-regression-json
+  baseline_path:
+    description: "Path for the baseline JSON in the workspace"
+    required: false
+    default: tests/perf-regression/perf-regression.json
+
+  # NOTE: defaults here must be literals; leave empty and resolve at runtime
+  workflow_name:
+    description: "Workflow display name to search runs for"
+    required: false
+    default: ""
+  branch:
+    description: "Branch to search prior runs on"
+    required: false
+    default: ""
+  target_repo:
+    description: "owner/repo to search in"
+    required: false
+    default: ""
+
+  run_command:
+    description: "Shell command to run perf tests (reads PERF_MODE env)"
+    required: false
+    default: sh run-ci-tests.sh
+
+runs:
+  using: "composite"
+  steps:
+    - name: Echo inputs
+      shell: bash
+      run: |
+        echo "mode=${{ inputs.mode }}"
+        echo "label_name=${{ inputs.label_name }}"
+        echo "artifact_name=${{ inputs.artifact_name }}"
+        echo "baseline_path=${{ inputs.baseline_path }}"
+        echo "workflow_name=${{ inputs.workflow_name }}"
+        echo "branch=${{ inputs.branch }}"
+        echo "target_repo=${{ inputs.target_repo }}"
+        echo "run_command=${{ inputs.run_command }}"
+
+    # Resolve workflow/repo/branch defaults using runtime contexts (allowed in steps)
+    - name: Resolve defaults
+      shell: bash
+      env:
+        IN_WORKFLOW: ${{ inputs.workflow_name }}
+        IN_BRANCH: ${{ inputs.branch }}
+        IN_REPO: ${{ inputs.target_repo }}
+        WF_CTX: ${{ github.workflow }}
+        HEAD_REF: ${{ github.head_ref }}
+        REF_NAME: ${{ github.ref_name }}
+        REPO_CTX: ${{ github.repository }}
+      run: |
+        set -euo pipefail
+        WF_NAME="${IN_WORKFLOW:-}"
+        [[ -z "$WF_NAME" ]] && WF_NAME="${WF_CTX}"
+
+        BRANCH="${IN_BRANCH:-}"
+        if [[ -z "$BRANCH" ]]; then
+          if [[ -n "${HEAD_REF}" ]]; then BRANCH="${HEAD_REF}"; else BRANCH="${REF_NAME}"; fi
+        fi
+
+        REPO="${IN_REPO:-}"
+        [[ -z "$REPO" ]] && REPO="${REPO_CTX}"
+
+        echo "WF_NAME=$WF_NAME" >> "$GITHUB_ENV"
+        echo "BRANCH=$BRANCH" >> "$GITHUB_ENV"
+        echo "TARGET_REPO=$REPO" >> "$GITHUB_ENV"
+        echo "Resolved: WF_NAME=$WF_NAME BRANCH=$BRANCH TARGET_REPO=$REPO"
+
+    - name: Resolve PERF_MODE
+      id: resolve-mode
+      shell: bash
+      env:
+        MODE: ${{ inputs.mode }}
+        LABEL_NAME: ${{ inputs.label_name }}
+        GH_TOKEN: ${{ github.token }}
+        EVENT_NAME: ${{ github.event_name }}
+        OWNER_REPO: ${{ github.repository }}
+        PR_NUMBER: ${{ github.event.pull_request.number }}
+      run: |
+        set -euo pipefail
+        MODE="${MODE:-auto}"
+        if [[ "$MODE" == "dump" ]]; then
+          PERF_MODE="--dump"
+        elif [[ "$MODE" == "check" ]]; then
+          PERF_MODE="--check"
+        else
+          if [[ "$EVENT_NAME" == "pull_request" ]]; then
+            LABELS=$(gh api "repos/$OWNER_REPO/issues/$PR_NUMBER/labels" --jq '.[].name' | tr '\n' ' ')
+            if echo "$LABELS" | grep -q -w "$LABEL_NAME"; then
+              PERF_MODE="--dump"
+            else
+              PERF_MODE="--check"
+            fi
+          else
+            PERF_MODE="--check"
+          fi
+        fi
+        echo "PERF_MODE=$PERF_MODE" | tee -a "$GITHUB_ENV"
+        echo "perf_mode=$PERF_MODE" >> "$GITHUB_OUTPUT"
+
+    # Only in check mode: find previous run with artifact and download it
+    - name: Find prior run with baseline
+      id: find-baseline
+      if: ${{ steps.resolve-mode.outputs.perf_mode == '--check' }}
+      shell: bash
+      env:
+        GH_TOKEN: ${{ github.token }}
+        TARGET_REPO: ${{ env.TARGET_REPO }}
+        WORKFLOW_NAME: ${{ env.WF_NAME }}
+        BRANCH: ${{ env.BRANCH }}
+        ARTIFACT_NAME: ${{ inputs.artifact_name }}
+      run: |
+        set -euo pipefail
+        echo "Searching $TARGET_REPO / '$WORKFLOW_NAME' / branch '$BRANCH' for artifact '$ARTIFACT_NAME'"
+        RUN_IDS=$(gh run list \
+          --repo "$TARGET_REPO" \
+          --workflow "$WORKFLOW_NAME" \
+          --json databaseId,headBranch,status,conclusion \
+          --limit 50 \
+          --jq "[.[] | select(.status==\"completed\" and .headBranch==\"$BRANCH\") | .databaseId] | .[]" \
+          || true)
+
+        if [[ -z "${RUN_IDS:-}" ]]; then
+          echo "No completed runs found on branch '$BRANCH' in $TARGET_REPO."
+          exit 1
+        fi
+
+        FOUND=""
+        for RID in $RUN_IDS; do
+          HAS=$(gh api "repos/$TARGET_REPO/actions/runs/$RID/artifacts" \
+            --jq ".artifacts | map(select(.name==\"$ARTIFACT_NAME\" and .expired==false)) | length")
+          echo "Run $RID has $HAS matching artifact(s)"
+          if [[ "$HAS" -gt 0 ]]; then FOUND="$RID"; break; fi
+        done
+
+        if [[ -z "${FOUND:-}" ]]; then
+          echo "No prior completed run on '$BRANCH' has artifact '$ARTIFACT_NAME'. Seed a baseline once."
+          exit 1
+        fi
+
+        echo "run_id=$FOUND" >> "$GITHUB_OUTPUT"
+
+    - name: Download baseline
+      if: ${{ steps.resolve-mode.outputs.perf_mode == '--check' }}
+      uses: actions/download-artifact@v4
+      with:
+        name: ${{ inputs.artifact_name }}
+        run-id: ${{ steps.find-baseline.outputs.run_id }}
+        path: tests/perf-regression
+        github-token: ${{ github.token }}
+
+    - name: Normalize baseline path
+      if: ${{ steps.resolve-mode.outputs.perf_mode == '--check' }}
+      shell: bash
+      env:
+        DEST: ${{ inputs.baseline_path }}
+      run: |
+        set -euo pipefail
+        FILE="$(find tests/perf-regression -name 'perf-regression.json' -print -quit || true)"
+        if [[ -z "${FILE:-}" ]]; then
+          echo "ERROR: perf-regression.json not found inside downloaded artifact."
+          ls -R tests/perf-regression || true
+          exit 1
+        fi
+        mkdir -p "$(dirname "$DEST")"
+        if [[ "$FILE" != "$DEST" ]]; then mv -f "$FILE" "$DEST"; fi
+        echo "Baseline ready at $DEST"
+
+    - name: Run perf tests
+      shell: bash
+      env:
+        PERF_MODE: ${{ env.PERF_MODE }}
+      run: ${{ inputs.run_command }}
+
+    - name: Upload baseline (dump mode only)
+      if: ${{ steps.resolve-mode.outputs.perf_mode == '--dump' }}
+      uses: actions/upload-artifact@v4
+      with:
+        name: ${{ inputs.artifact_name }}
+        path: ${{ inputs.baseline_path }}
+        if-no-files-found: error
+        retention-days: 30
diff --git a/.github/actions/upload-perf-baseline/action.yml b/.github/actions/upload-perf-baseline/action.yml
deleted file mode 100644
index 59fab5ca26..0000000000
--- a/.github/actions/upload-perf-baseline/action.yml
+++ /dev/null
@@ -1,35 +0,0 @@
-name: Upload Perf Baseline (optional)
-description: Upload perf-regression.json only when PERF_MODE is --dump.
-inputs:
-  perf_mode:
-    description: "--dump or --check"
-    required: true
-  path:
-    description: "Path to perf baseline JSON"
-    required: false
-    default: tests/perf-regression/perf-regression.json
-  name:
-    description: "Artifact name"
-    required: false
-    default: perf-regression-json
-  retention-days:
-    description: "Artifact retention (days)"
-    required: false
-    default: "30"
-
-runs:
-  using: "composite"
-  steps:
-    - name: Skip unless in dump mode
-      if: inputs.perf_mode != '--dump'
-      shell: bash
-      run: echo "Not in --dump mode; skipping upload."
-
-    - name: Upload baseline
-      if: inputs.perf_mode == '--dump'
-      uses: actions/upload-artifact@v4
-      with:
-        name: ${{ inputs.name }}
-        path: ${{ inputs.path }}
-        if-no-files-found: error
-        retention-days: ${{ inputs.retention-days }}
diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index c68cc40739..d37e313767 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -175,96 +175,26 @@ jobs:
           credentials_json: '${{ secrets.GCP_O1JS_CI_BUCKET_SERVICE_ACCOUNT_KEY }}'
       - name: Prepare for tests
         run: touch profiling.md
-      - name: Find a prior run that actually has perf baseline
-        id: find-baseline
-        if: >
-          matrix.test_type == 'Performance Regression' && !contains(github.event.pull_request.labels.*.name, 'dump-performance')
-        env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          TARGET_REPO: ${{ inputs.target_repo || github.repository }}
-          WORKFLOW_NAME: ${{ github.workflow }}   # display name, e.g. "Checks"
-          BRANCH: ${{ github.head_ref || github.ref_name }}
-          ARTIFACT_NAME: perf-regression-json
-        run: |
-          set -euo pipefail
-
-          echo "Looking for completed prior runs of '$WORKFLOW_NAME' on '$BRANCH' in $TARGET_REPO with artifact '$ARTIFACT_NAME'"
-
-          # List recent COMPLETED runs (don't require 'success' to survive matrix failures)
-          RUN_IDS=$(gh run list \
-            --repo "$TARGET_REPO" \
-            --workflow "$WORKFLOW_NAME" \
-            --json databaseId,headBranch,status,conclusion \
-            --limit 40 \
-            --jq "[.[] | select(.status==\"completed\" and .headBranch==\"$BRANCH\") | .databaseId] | .[]" \
-            || true)
-
-          if [[ -z "${RUN_IDS:-}" ]]; then
-            echo "No completed runs found on this branch in $TARGET_REPO."
-            echo "Seed a baseline once (add 'dump-performance' label) or relax branch to 'main' later."
-            exit 1
-          fi
-
-          # Pick the first run that actually has the artifact and it's not expired
-          FOUND=""
-          for RID in $RUN_IDS; do
-            HAS=$(gh api repos/"$TARGET_REPO"/actions/runs/"$RID"/artifacts \
-              --jq ".artifacts | map(select(.name==\"$ARTIFACT_NAME\" and .expired==false)) | length")
-            echo "Run $RID has $HAS matching artifact(s)."
-            if [[ "$HAS" -gt 0 ]]; then
-              FOUND="$RID"
-              break
-            fi
-          done
-
-          if [[ -z "${FOUND:-}" ]]; then
-            echo "No prior completed run on '$BRANCH' has artifact '$ARTIFACT_NAME'."
-            echo "Seed a baseline once (add 'dump-performance' label) so check mode can download it."
-            exit 1
-          fi
-
-          echo "run_id=$FOUND" >> "$GITHUB_OUTPUT"
-          echo "Found suitable run id: $FOUND"
-      - name: Download baseline artifact from that run
-        if: >
-          matrix.test_type == 'Performance Regression' && !contains(github.event.pull_request.labels.*.name, 'dump-performance')
-        uses: actions/download-artifact@v4
-        with:
-          name: perf-regression-json
-          run-id: ${{ steps.find-baseline.outputs.run_id }}
-          path: tests/perf-regression
-          github-token: ${{ secrets.GITHUB_TOKEN }}
-      - name: Normalize baseline path for the script
-        if: >
-          matrix.test_type == 'Performance Regression' &&!contains(github.event.pull_request.labels.*.name, 'dump-performance')
-        run: |
-          set -euo pipefail 
-          FILE="$(find tests/perf-regression -name 'perf-regression.json' -print -quit || true)"
-          if [[ -z "${FILE:-}" ]]; then
-            echo "ERROR: perf-regression.json not found inside downloaded artifact."
-            echo "Listing:"
-            ls -R tests/perf-regression || true
-            exit 1
-          fi
-          if [[ "$FILE" != "tests/perf-regression/perf-regression.json" ]]; then
-            mv -f "$FILE" tests/perf-regression/perf-regression.json
-          fi
-          echo "Baseline ready at tests/perf-regression/perf-regression.json"
       - name: Execute tests
+        if: matrix.test_type != 'Performance Regression'
         env:
           TEST_TYPE: ${{ matrix.test_type }}
-          PERF_MODE: ${{ contains(github.event.pull_request.labels.*.name, 'dump-performance') && '--dump' || '--check' }}
         run: sh run-ci-tests.sh
-      - name: Upload performance regressions baseline
-        if: >
-          matrix.test_type == 'Performance Regression' &&
-          contains(github.event.pull_request.labels.*.name, 'dump-performance')
-        uses: ./.github/actions/upload-perf-baseline
+
+      - name: Perf regression (dump/check)
+        if: matrix.test_type == 'Performance Regression'
+        uses: ./.github/actions/perf-regression
+        env:
+          TEST_TYPE: Performance Regression
         with:
-          perf_mode: ${{ contains(github.event.pull_request.labels.*.name, 'dump-performance') && '--dump' || '--check' }}
-          path: tests/perf-regression/perf-regression.json
-          name: perf-regression-json
-          retention-days: 30
+          mode: auto
+          label_name: dump-performance
+          artifact_name: perf-regression-json
+          baseline_path: tests/perf-regression/perf-regression.json
+          workflow_name: ${{ github.workflow }}
+          branch: ${{ github.head_ref || github.ref_name }}
+          target_repo: ${{ inputs.target_repo || github.repository }}
+          run_command: sh run-ci-tests.sh
       - name: Add to job summary
         if: always()
         run: |

From 8ba94f24c517ba24741794019476b80ae300baf6 Mon Sep 17 00:00:00 2001
From: Shigoto-dev19 <shigoto-dev19@protonmail.com>
Date: Wed, 15 Oct 2025 16:35:46 +0300
Subject: [PATCH 6/7] Refine naming in performance regression CI action

---
 .github/actions/perf-regression/action.yml | 85 ++++++++++------------
 .github/workflows/checks.yml               |  3 +-
 2 files changed, 38 insertions(+), 50 deletions(-)

diff --git a/.github/actions/perf-regression/action.yml b/.github/actions/perf-regression/action.yml
index 23e0f7b95e..8329311cbc 100644
--- a/.github/actions/perf-regression/action.yml
+++ b/.github/actions/perf-regression/action.yml
@@ -1,28 +1,27 @@
-name: Perf Regression (dump/check)
-description: Dump or check perf baseline; auto mode via label; find/download prior baseline; run tests; upload on dump.
+name: Performance Regression (Dump or Check)
+description: Runs performance regression tests in dump or check mode. Auto mode determines the mode based on the PR label.
 
 inputs:
   mode:
-    description: "'dump' | 'check' | 'auto' (auto uses live PR labels)"
+    description: "'dump' | 'check' | 'auto' (auto uses the PR label)"
     required: false
     default: auto
   label_name:
-    description: "Label that triggers dump when present (auto mode)"
+    description: "Label that enables dump mode when present (auto mode)"
     required: false
     default: dump-performance
 
   artifact_name:
-    description: "Artifact name used to store the baseline"
+    description: "Artifact name used to store the performance baseline JSON"
     required: false
     default: perf-regression-json
   baseline_path:
-    description: "Path for the baseline JSON in the workspace"
+    description: "Path where the performance baseline JSON is stored"
     required: false
     default: tests/perf-regression/perf-regression.json
 
-  # NOTE: defaults here must be literals; leave empty and resolve at runtime
   workflow_name:
-    description: "Workflow display name to search runs for"
+    description: "Workflow name to search for prior runs"
     required: false
     default: ""
   branch:
@@ -35,27 +34,14 @@ inputs:
     default: ""
 
   run_command:
-    description: "Shell command to run perf tests (reads PERF_MODE env)"
+    description: "Shell command to run performance tests (reads PERF_MODE env)"
     required: false
     default: sh run-ci-tests.sh
 
 runs:
   using: "composite"
   steps:
-    - name: Echo inputs
-      shell: bash
-      run: |
-        echo "mode=${{ inputs.mode }}"
-        echo "label_name=${{ inputs.label_name }}"
-        echo "artifact_name=${{ inputs.artifact_name }}"
-        echo "baseline_path=${{ inputs.baseline_path }}"
-        echo "workflow_name=${{ inputs.workflow_name }}"
-        echo "branch=${{ inputs.branch }}"
-        echo "target_repo=${{ inputs.target_repo }}"
-        echo "run_command=${{ inputs.run_command }}"
-
-    # Resolve workflow/repo/branch defaults using runtime contexts (allowed in steps)
-    - name: Resolve defaults
+    - name: Resolve workflow and repository context
       shell: bash
       env:
         IN_WORKFLOW: ${{ inputs.workflow_name }}
@@ -67,23 +53,19 @@ runs:
         REPO_CTX: ${{ github.repository }}
       run: |
         set -euo pipefail
-        WF_NAME="${IN_WORKFLOW:-}"
-        [[ -z "$WF_NAME" ]] && WF_NAME="${WF_CTX}"
-
-        BRANCH="${IN_BRANCH:-}"
-        if [[ -z "$BRANCH" ]]; then
-          if [[ -n "${HEAD_REF}" ]]; then BRANCH="${HEAD_REF}"; else BRANCH="${REF_NAME}"; fi
-        fi
-
-        REPO="${IN_REPO:-}"
-        [[ -z "$REPO" ]] && REPO="${REPO_CTX}"
+        WF_NAME="${IN_WORKFLOW:-$WF_CTX}"
+        BRANCH="${IN_BRANCH:-${HEAD_REF:-$REF_NAME}}"
+        REPO="${IN_REPO:-$REPO_CTX}"
 
         echo "WF_NAME=$WF_NAME" >> "$GITHUB_ENV"
         echo "BRANCH=$BRANCH" >> "$GITHUB_ENV"
         echo "TARGET_REPO=$REPO" >> "$GITHUB_ENV"
-        echo "Resolved: WF_NAME=$WF_NAME BRANCH=$BRANCH TARGET_REPO=$REPO"
+        echo "Resolved context:"
+        echo "  Workflow: $WF_NAME"
+        echo "  Branch: $BRANCH"
+        echo "  Repository: $REPO"
 
-    - name: Resolve PERF_MODE
+    - name: Determine dump or check mode
       id: resolve-mode
       shell: bash
       env:
@@ -98,25 +80,31 @@ runs:
         MODE="${MODE:-auto}"
         if [[ "$MODE" == "dump" ]]; then
           PERF_MODE="--dump"
+          REASON="explicit input"
         elif [[ "$MODE" == "check" ]]; then
           PERF_MODE="--check"
+          REASON="explicit input"
         else
           if [[ "$EVENT_NAME" == "pull_request" ]]; then
             LABELS=$(gh api "repos/$OWNER_REPO/issues/$PR_NUMBER/labels" --jq '.[].name' | tr '\n' ' ')
             if echo "$LABELS" | grep -q -w "$LABEL_NAME"; then
               PERF_MODE="--dump"
+              REASON="label $LABEL_NAME present"
             else
               PERF_MODE="--check"
+              REASON="label $LABEL_NAME absent"
             fi
           else
             PERF_MODE="--check"
+            REASON="non-PR event"
           fi
         fi
+
         echo "PERF_MODE=$PERF_MODE" | tee -a "$GITHUB_ENV"
         echo "perf_mode=$PERF_MODE" >> "$GITHUB_OUTPUT"
+        echo "Mode: $PERF_MODE ($REASON)"
 
-    # Only in check mode: find previous run with artifact and download it
-    - name: Find prior run with baseline
+    - name: Find prior run with performance baseline artifact
       id: find-baseline
       if: ${{ steps.resolve-mode.outputs.perf_mode == '--check' }}
       shell: bash
@@ -128,7 +116,7 @@ runs:
         ARTIFACT_NAME: ${{ inputs.artifact_name }}
       run: |
         set -euo pipefail
-        echo "Searching $TARGET_REPO / '$WORKFLOW_NAME' / branch '$BRANCH' for artifact '$ARTIFACT_NAME'"
+        echo "Searching $TARGET_REPO (workflow: $WORKFLOW_NAME, branch: $BRANCH) for artifact $ARTIFACT_NAME..."
         RUN_IDS=$(gh run list \
           --repo "$TARGET_REPO" \
           --workflow "$WORKFLOW_NAME" \
@@ -138,7 +126,7 @@ runs:
           || true)
 
         if [[ -z "${RUN_IDS:-}" ]]; then
-          echo "No completed runs found on branch '$BRANCH' in $TARGET_REPO."
+          echo "No completed runs found on branch $BRANCH."
           exit 1
         fi
 
@@ -146,18 +134,19 @@ runs:
         for RID in $RUN_IDS; do
           HAS=$(gh api "repos/$TARGET_REPO/actions/runs/$RID/artifacts" \
             --jq ".artifacts | map(select(.name==\"$ARTIFACT_NAME\" and .expired==false)) | length")
-          echo "Run $RID has $HAS matching artifact(s)"
+          echo "Run $RID → $HAS artifact(s)"
           if [[ "$HAS" -gt 0 ]]; then FOUND="$RID"; break; fi
         done
 
         if [[ -z "${FOUND:-}" ]]; then
-          echo "No prior completed run on '$BRANCH' has artifact '$ARTIFACT_NAME'. Seed a baseline once."
+          echo "No suitable run with artifact $ARTIFACT_NAME found."
           exit 1
         fi
 
         echo "run_id=$FOUND" >> "$GITHUB_OUTPUT"
+        echo "Found performance baseline in run: $FOUND"
 
-    - name: Download baseline
+    - name: Download performance baseline artifact
       if: ${{ steps.resolve-mode.outputs.perf_mode == '--check' }}
       uses: actions/download-artifact@v4
       with:
@@ -166,7 +155,7 @@ runs:
         path: tests/perf-regression
         github-token: ${{ github.token }}
 
-    - name: Normalize baseline path
+    - name: Normalize performance baseline path
       if: ${{ steps.resolve-mode.outputs.perf_mode == '--check' }}
       shell: bash
       env:
@@ -175,21 +164,21 @@ runs:
         set -euo pipefail
         FILE="$(find tests/perf-regression -name 'perf-regression.json' -print -quit || true)"
         if [[ -z "${FILE:-}" ]]; then
-          echo "ERROR: perf-regression.json not found inside downloaded artifact."
+          echo "ERROR: perf-regression.json not found."
           ls -R tests/perf-regression || true
           exit 1
         fi
         mkdir -p "$(dirname "$DEST")"
-        if [[ "$FILE" != "$DEST" ]]; then mv -f "$FILE" "$DEST"; fi
-        echo "Baseline ready at $DEST"
+        [[ "$FILE" != "$DEST" ]] && mv -f "$FILE" "$DEST"
+        echo "Performance Baseline ready at: $DEST"
 
-    - name: Run perf tests
+    - name: Run performance regression tests
       shell: bash
       env:
         PERF_MODE: ${{ env.PERF_MODE }}
       run: ${{ inputs.run_command }}
 
-    - name: Upload baseline (dump mode only)
+    - name: Upload new performance baseline (dump mode)
       if: ${{ steps.resolve-mode.outputs.perf_mode == '--dump' }}
       uses: actions/upload-artifact@v4
       with:
diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index d37e313767..3a448ee194 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -180,8 +180,7 @@ jobs:
         env:
           TEST_TYPE: ${{ matrix.test_type }}
         run: sh run-ci-tests.sh
-
-      - name: Perf regression (dump/check)
+      - name: Performance Regression (dump or check)
         if: matrix.test_type == 'Performance Regression'
         uses: ./.github/actions/perf-regression
         env:

From d15de7fde5fbb67d8812b9278ff3c9240962f909 Mon Sep 17 00:00:00 2001
From: Shigoto-dev19 <shigoto-dev19@protonmail.com>
Date: Wed, 15 Oct 2025 17:07:57 +0300
Subject: [PATCH 7/7] Make performance regression CI checks use main as
 baseline source

---
 .github/actions/perf-regression/action.yml | 89 ++++++++++++++--------
 .github/workflows/checks.yml               |  2 +-
 2 files changed, 57 insertions(+), 34 deletions(-)

diff --git a/.github/actions/perf-regression/action.yml b/.github/actions/perf-regression/action.yml
index 8329311cbc..1930665cc3 100644
--- a/.github/actions/perf-regression/action.yml
+++ b/.github/actions/perf-regression/action.yml
@@ -1,9 +1,9 @@
 name: Performance Regression (Dump or Check)
-description: Runs performance regression tests in dump or check mode. Auto mode determines the mode based on the PR label.
+description: Runs performance regression tests in dump or check mode. Auto mode decides via PR label on PRs, and via merged PR labels on push to main.
 
 inputs:
   mode:
-    description: "'dump' | 'check' | 'auto' (auto uses the PR label)"
+    description: "'dump' | 'check' | 'auto' (auto uses labels)"
     required: false
     default: auto
   label_name:
@@ -21,15 +21,15 @@ inputs:
     default: tests/perf-regression/perf-regression.json
 
   workflow_name:
-    description: "Workflow name to search for prior runs"
+    description: "Workflow name to search when locating prior runs (defaults to current)"
     required: false
     default: ""
   branch:
-    description: "Branch to search prior runs on"
+    description: "Branch to search prior runs on (defaults to main)"
     required: false
-    default: ""
+    default: "main"
   target_repo:
-    description: "owner/repo to search in"
+    description: "owner/repo to search in (defaults to current)"
     required: false
     default: ""
 
@@ -48,22 +48,20 @@ runs:
         IN_BRANCH: ${{ inputs.branch }}
         IN_REPO: ${{ inputs.target_repo }}
         WF_CTX: ${{ github.workflow }}
-        HEAD_REF: ${{ github.head_ref }}
-        REF_NAME: ${{ github.ref_name }}
         REPO_CTX: ${{ github.repository }}
       run: |
         set -euo pipefail
         WF_NAME="${IN_WORKFLOW:-$WF_CTX}"
-        BRANCH="${IN_BRANCH:-${HEAD_REF:-$REF_NAME}}"
+        BRANCH="${IN_BRANCH}"   # default is "main" unless caller overrides
         REPO="${IN_REPO:-$REPO_CTX}"
 
         echo "WF_NAME=$WF_NAME" >> "$GITHUB_ENV"
         echo "BRANCH=$BRANCH" >> "$GITHUB_ENV"
         echo "TARGET_REPO=$REPO" >> "$GITHUB_ENV"
-        echo "Resolved context:"
-        echo "  Workflow: $WF_NAME"
-        echo "  Branch: $BRANCH"
-        echo "  Repository: $REPO"
+
+        echo "Using workflow: $WF_NAME"
+        echo "Searching performance baselines on branch: $BRANCH"
+        echo "Target repository: $REPO"
 
     - name: Determine dump or check mode
       id: resolve-mode
@@ -75,28 +73,52 @@ runs:
         EVENT_NAME: ${{ github.event_name }}
         OWNER_REPO: ${{ github.repository }}
         PR_NUMBER: ${{ github.event.pull_request.number }}
+        GIT_REF: ${{ github.ref }}
+        GIT_SHA: ${{ github.sha }}
       run: |
         set -euo pipefail
+
+        decide_from_pr_labels () {
+          local repo="$1" pr="$2" label="$3"
+          local labels
+          labels=$(gh api "repos/$repo/issues/$pr/labels" --jq '.[].name' | tr '\n' ' ')
+          if echo "$labels" | grep -q -w "$label"; then
+            echo "--dump"
+          else
+            echo "--check"
+          fi
+        }
+
+        decide_from_merged_pr_labels () {
+          local repo="$1" sha="$2" label="$3"
+          local prs should_dump=0
+          prs=$(gh api "repos/$repo/commits/$sha/pulls" --jq '.[].number' || true)
+          for n in $prs; do
+            local ls
+            ls=$(gh api "repos/$repo/issues/$n/labels" --jq '.[].name' | tr '\n' ' ')
+            if echo "$ls" | grep -q -w "$label"; then
+              should_dump=1; break
+            fi
+          done
+          if [[ $should_dump -eq 1 ]]; then echo "--dump"; else echo "--check"; fi
+        }
+
         MODE="${MODE:-auto}"
+        REASON=""
+
         if [[ "$MODE" == "dump" ]]; then
-          PERF_MODE="--dump"
-          REASON="explicit input"
+          PERF_MODE="--dump"; REASON="explicit input"
         elif [[ "$MODE" == "check" ]]; then
-          PERF_MODE="--check"
-          REASON="explicit input"
+          PERF_MODE="--check"; REASON="explicit input"
         else
           if [[ "$EVENT_NAME" == "pull_request" ]]; then
-            LABELS=$(gh api "repos/$OWNER_REPO/issues/$PR_NUMBER/labels" --jq '.[].name' | tr '\n' ' ')
-            if echo "$LABELS" | grep -q -w "$LABEL_NAME"; then
-              PERF_MODE="--dump"
-              REASON="label $LABEL_NAME present"
-            else
-              PERF_MODE="--check"
-              REASON="label $LABEL_NAME absent"
-            fi
+            PERF_MODE="$(decide_from_pr_labels "$OWNER_REPO" "$PR_NUMBER" "$LABEL_NAME")"
+            REASON="PR label check"
+          elif [[ "$EVENT_NAME" == "push" && "$GIT_REF" == "refs/heads/main" ]]; then
+            PERF_MODE="$(decide_from_merged_pr_labels "$OWNER_REPO" "$GIT_SHA" "$LABEL_NAME")"
+            REASON="merged PR label check"
           else
-            PERF_MODE="--check"
-            REASON="non-PR event"
+            PERF_MODE="--check"; REASON="default for non-PR, non-main push"
           fi
         fi
 
@@ -104,7 +126,7 @@ runs:
         echo "perf_mode=$PERF_MODE" >> "$GITHUB_OUTPUT"
         echo "Mode: $PERF_MODE ($REASON)"
 
-    - name: Find prior run with performance baseline artifact
+    - name: Find prior run with performance baseline artifact (from target branch)
       id: find-baseline
       if: ${{ steps.resolve-mode.outputs.perf_mode == '--check' }}
       shell: bash
@@ -116,7 +138,8 @@ runs:
         ARTIFACT_NAME: ${{ inputs.artifact_name }}
       run: |
         set -euo pipefail
-        echo "Searching $TARGET_REPO (workflow: $WORKFLOW_NAME, branch: $BRANCH) for artifact $ARTIFACT_NAME..."
+        echo "Searching $TARGET_REPO (workflow: $WORKFLOW_NAME, branch: $BRANCH) for artifact $ARTIFACT_NAME"
+
         RUN_IDS=$(gh run list \
           --repo "$TARGET_REPO" \
           --workflow "$WORKFLOW_NAME" \
@@ -134,17 +157,17 @@ runs:
         for RID in $RUN_IDS; do
           HAS=$(gh api "repos/$TARGET_REPO/actions/runs/$RID/artifacts" \
             --jq ".artifacts | map(select(.name==\"$ARTIFACT_NAME\" and .expired==false)) | length")
-          echo "Run $RID → $HAS artifact(s)"
+          echo "Run $RID has $HAS matching artifact(s)"
           if [[ "$HAS" -gt 0 ]]; then FOUND="$RID"; break; fi
         done
 
         if [[ -z "${FOUND:-}" ]]; then
-          echo "No suitable run with artifact $ARTIFACT_NAME found."
+          echo "No suitable run with artifact $ARTIFACT_NAME found on $BRANCH."
           exit 1
         fi
 
         echo "run_id=$FOUND" >> "$GITHUB_OUTPUT"
-        echo "Found performance baseline in run: $FOUND"
+        echo "Using performance baseline from run: $FOUND"
 
     - name: Download performance baseline artifact
       if: ${{ steps.resolve-mode.outputs.perf_mode == '--check' }}
@@ -164,7 +187,7 @@ runs:
         set -euo pipefail
         FILE="$(find tests/perf-regression -name 'perf-regression.json' -print -quit || true)"
         if [[ -z "${FILE:-}" ]]; then
-          echo "ERROR: perf-regression.json not found."
+          echo "ERROR: perf-regression.json not found in downloaded artifact."
           ls -R tests/perf-regression || true
           exit 1
         fi
diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index 3a448ee194..bb5f0daa21 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -191,7 +191,7 @@ jobs:
           artifact_name: perf-regression-json
           baseline_path: tests/perf-regression/perf-regression.json
           workflow_name: ${{ github.workflow }}
-          branch: ${{ github.head_ref || github.ref_name }}
+          branch: main               
           target_repo: ${{ inputs.target_repo || github.repository }}
           run_command: sh run-ci-tests.sh
       - name: Add to job summary