Increase CI sharding

.github/actions/ci-checks/action.yml

@@ -43,10 +43,10 @@ runs:
       run: ./scripts/ci-runners.sh
       shell: bash
     - if: ${{ startsWith(inputs.check, 'tests-') }}
-      run: ./scripts/ci-tests.sh $(sed s/tests-// <<< ${{ inputs.check }}) 8
+      run: ./scripts/ci-tests.sh $(sed s/tests-// <<< ${{ inputs.check }}) 11
       shell: bash
-    - if: ${{ inputs.check == 'hw-host' }}
-      run: ./scripts/hwci.sh host
+    - if: ${{ startsWith(inputs.check, 'hw-host-') }}
+      run: SHARDING="$(sed s/hw-host-// <<< ${{ inputs.check }}) 2" ./scripts/hwci.sh host
       shell: bash
     - if: ${{ inputs.check == 'book' }}
       run: ./scripts/ci-book.sh

.github/workflows/ci.yml

@@ -31,21 +31,23 @@ jobs:
             done
             true
           }
-          x   copyright  pull_request
-          x   changelog  pull_request
-          x  textreview  pull_request
-          x        sync  pull_request  push  schedule
-          x     publish  pull_request  push  schedule
-          x    markdown  pull_request  push  schedule
-          x       taplo  pull_request  push  schedule
-          x     applets  pull_request  push  schedule
-          x     runners  pull_request  push  schedule
-          for i in $(seq 0 7); do
-            x  tests-$i  pull_request  push  schedule
+          x    copyright  pull_request
+          x    changelog  pull_request
+          x   textreview  pull_request
+          x         sync  pull_request  push  schedule
+          x      publish  pull_request  push  schedule
+          x     markdown  pull_request  push  schedule
+          x        taplo  pull_request  push  schedule
+          x      applets  pull_request  push  schedule
+          x      runners  pull_request  push  schedule
+          for i in $(seq 0 10); do
+            x   tests-$i  pull_request  push  schedule
           done
-          x     hw-host  pull_request  push  schedule
-          x        book  pull_request  push  schedule
-          x   footprint  pull_request  push
+          for i in $(seq 0 1); do
+            x hw-host-$i  pull_request  push  schedule
+          done
+          x         book  pull_request  push  schedule
+          x    footprint  pull_request  push
           echo "checks=[$CHECKS]" >> $GITHUB_OUTPUT
           release=$(git log -1 --pretty=%s | sed -n 's/^Release all crates (#\([0-9]*\))$/\1/p')
           [[ $GITHUB_EVENT_NAME == push ]] || release=

scripts/ci-tests.sh

@@ -15,16 +15,13 @@
 
 set -e
 . scripts/log.sh
+. scripts/shard.sh
 
 # This script runs the continuous integration tests.
 
-K=${1:-0}
-M=${2:-1}
-
-i=$(( M - 1 ))
+shard_init "$@"
 for dir in $(git ls-files '*/test.sh'); do
-  i=$(( (i + 1) % M ))
-  [ $i -eq $K ] || continue
+  shard_next || continue
   grep -q test-helper $dir || e "$dir doesn't use test-helper.sh"
   dir=$(dirname $dir)
   i "Run tests in $dir"

scripts/hwci.sh

@@ -16,6 +16,7 @@
 set -e
 . scripts/log.sh
 . scripts/package.sh
+. scripts/shard.sh
 
 # This script runs the test applets and thus needs a connected platform.
 #
@@ -39,7 +40,9 @@ run() {
   local name name_flags feature features
   local runner_specific runner_feature runner_default
   shift 2
+  shard_init $SHARDING
   for name in $(list); do
+    shard_next || continue
     runner_specific=n
     runner_feature=
     runner_default=n

scripts/shard.sh

@@ -0,0 +1,24 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+shard_init() {
+  _SHARD_INDEX=${1:-0}
+  _SHARD_COUNT=${2:-1}
+  _shard_index=$(( _SHARD_COUNT - 1 ))
+}
+
+shard_next() {
+  _shard_index=$(( (_shard_index + 1) % _SHARD_COUNT ))
+  [ $_shard_index -eq $_SHARD_INDEX ]
+}