adding benchmarking script to start monitoring build times

- makes use of the gradle-profiler to run the build multiple times
- currently uses reduced warm up/iteration count as the build takes a long time, can be increased once the build time is reduced

.gitignore

@@ -8,6 +8,7 @@
 .idea/*.xml
 .DS_Store
 /build
+/benchmark-out
 /captures
 .externalNativeBuild
 

tools/benchmark/benchmark.profile

@@ -0,0 +1,39 @@
+#
+# Copyright 2021 New Vector Ltd
+#
+# 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.
+#
+
+clean_assemble {
+  tasks = ["clean", ":vector:assembleGPlayDebug"]
+}
+
+clean_assemble_build_cache {
+  tasks = ["clean", ":vector:assembleGPlayDebug"]
+  gradle-args = ["--build-cache"]
+}
+
+clean_assemble_without_cache {
+  tasks = ["clean", ":vector:assembleGPlayDebug"]
+  gradle-args = ["--no-build-cache"]
+}
+
+incremental_assemble_sdk_abi {
+  tasks = [":vector:assembleGPlayDebug"]
+  apply-abi-change-to = "matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/Matrix.kt"
+}
+
+incremental_assemble_sdk_no_abi {
+  tasks = [":vector:assembleGPlayDebug"]
+  apply-non-abi-change-to = "matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/Matrix.kt"
+}

tools/benchmark/run_benchmark.sh

@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+
+#
+# Copyright 2021 New Vector Ltd
+#
+# 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.
+#
+
+if ! command -v gradle-profiler &> /dev/null
+then
+    echo "gradle-profiler could not be found https://github.com/gradle/gradle-profiler"
+    exit
+fi
+
+gradle-profiler \
+  --benchmark \
+  --project-dir . \
+  --scenario-file tools/benchmark/benchmark.profile \
+  --output-dir benchmark-out/output \
+  --gradle-user-home benchmark-out/gradle-home \
+  --warmups 3 \
+  --iterations 3 \
+  $1