skip inconsistent shards if possible (#13945)

data shards were wrong due to a healing bug
reported in #13803 mainly with unaligned object
sizes.

This PR is an attempt to automatically avoid
these shards, with available information about
the `xl.meta` and actually disk mtime.

.github/workflows/go-healing.yml

@@ -0,0 +1,48 @@
+name: Healing Functional Tests
+
+on:
+  pull_request:
+    branches:
+    - master
+
+# This ensures that previous jobs for the PR are canceled when the PR is
+# updated.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref }}
+  cancel-in-progress: true
+
+jobs:
+  build:
+    name: Go ${{ matrix.go-version }} on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        go-version: [1.17.x]
+        os: [ubuntu-latest]
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-go@v2
+        with:
+          go-version: ${{ matrix.go-version }}
+      - uses: actions/cache@v2
+        with:
+          path: |
+            ~/.cache/go-build
+            ~/go/pkg/mod
+          key: ${{ runner.os }}-${{ matrix.go-version }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-${{ matrix.go-version }}-go-
+      - name: Build on ${{ matrix.os }}
+        if: matrix.os == 'ubuntu-latest'
+        env:
+          CGO_ENABLED: 0
+          GO111MODULE: on
+          MINIO_KMS_KES_CERT_FILE: /home/runner/work/minio/minio/.github/workflows/root.cert
+          MINIO_KMS_KES_KEY_FILE: /home/runner/work/minio/minio/.github/workflows/root.key
+          MINIO_KMS_KES_ENDPOINT: "https://play.min.io:7373"
+          MINIO_KMS_KES_KEY_NAME: "my-minio-key"
+          MINIO_KMS_AUTO_ENCRYPTION: on
+        run: |
+          sudo sysctl net.ipv6.conf.all.disable_ipv6=0
+          sudo sysctl net.ipv6.conf.default.disable_ipv6=0
+          make verify-healing

.github/workflows/go.yml

@@ -13,7 +13,7 @@ concurrency:
 
 jobs:
   build:
-    name: Go ${{ matrix.go-version }} on ${{ matrix.os }}
+    name: Go ${{ matrix.go-version }} on ${{ matrix.os }} - healing
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
@@ -46,4 +46,3 @@ jobs:
           sudo sysctl net.ipv6.conf.all.disable_ipv6=0
           sudo sysctl net.ipv6.conf.default.disable_ipv6=0
           make verify
-          make verify-healing