GitHub Actions CI中缓存的命中率为0.00%

Question

我有一个伪C++项目，我有以下github操作配置：

name: CI
on: [push, pull_request] # on all pushes and PRs
jobs:
dummy:
runs-on: ubuntu-latest
strategy:
matrix:
distro: ["ros:foxy-ros-base-focal"]
container:
image: ${{ matrix.distro }}
env:
CCACHE_DIR: "${{ github.workspace }}/.ccache"
steps:
- uses: actions/checkout@v2
- name: install ccache
run: |
sudo apt-get update -y
sudo apt-get -qq install ccache
- name: ccache cache
uses: actions/cache@v2
with:
path: ${{ env.CCACHE_DIR }}
key: ccache-${{ matrix.distro }}-${{github.run_id}}
restore-keys: |
ccache-${{ matrix.distro }}
- name: ccache stats
run: ccache -s
- name: Build workspace
run: |
bash ./build_bridge.sh

我正在通过在CMakeLists.txt中添加/删除库来测试ccache，但每次ccache的命中率为0%

cache directory                     /__w/action_test/action_test/.ccache
primary config                      /__w/action_test/action_test/.ccache/ccache.conf
secondary config      (readonly)    /etc/ccache.conf
cache hit (direct)                     0
cache hit (preprocessed)               0
cache miss                             0
cache hit rate                      0.00 %
cleanups performed                     0
files in cache                         0
cache size                           0.0 kB
max cache size                       5.0 GB

从中恢复缓存的上一个作业有一个输出：

Post job cleanup.
/usr/bin/docker exec  b170bb77ebaac32aed0561984bb959d515d8a025b9329b6309b986f6b676c6c4 sh -c "cat /etc/*release | grep ^ID"
/usr/bin/tar --posix -z -cf cache.tgz -P -C /__w/action_test/action_test --files-from manifest.txt
Cache saved successfully

我需要做任何特定的事情来保存cmake特定的缓存吗？

Answer 1

CMake应该使用ccache的编译器包装引用："在您的项目中启用ccache；。我将构建步骤修改为：

- name: Build workspace
run: |
sudo /usr/sbin/update-ccache-symlinks
export PATH="/usr/lib/ccache:$PATH"
bash ./build_bridge.sh

CMake输出：

-- Check for working C compiler: /usr/lib/ccache/cc -- works
-- Check for working CXX compiler: /usr/lib/ccache/c++ -- works

现在ccache的统计数据看起来不错

stats updated                       Wed Mar 31 17:30:50 2021
cache hit (direct)                     1
cache hit (preprocessed)               0
cache miss                            48
cache hit rate                      2.04 %
called for link                       41
cleanups performed                     0
files in cache                        94
cache size                          42.8 MB
max cache size                       5.0 GB

构建时间从1分钟~20秒缩短到24秒。