[RFC PATCH] gitlab: aggressively avoid extra GIT data

[Alex Bennée]

This avoids fetching blobs and tree references for branches we are not
going to worry about. Also skip tag references which are similarly not
useful and keep the default --prune. This keeps the .git data to
around 100M rather than the ~400M even a shallow clone takes.

So we can check the savings we also run a quick du while setting up
the build.

We also have to have special settings of GIT_FETCH_EXTRA_FLAGS for the
Windows build (git too old?) and the migration legacy test where we
build an older QEMU alongside the main one.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
---
 .gitlab-ci.d/base.yml               | 4 ++++
 .gitlab-ci.d/buildtest-template.yml | 1 +
 .gitlab-ci.d/buildtest.yml          | 2 ++
 .gitlab-ci.d/windows.yml            | 2 ++
 4 files changed, 9 insertions(+)

diff --git a/.gitlab-ci.d/base.yml b/.gitlab-ci.d/base.yml
index ef173a34e6..7cb800fc3b 100644
--- a/.gitlab-ci.d/base.yml
+++ b/.gitlab-ci.d/base.yml
@@ -24,6 +24,10 @@ variables:
     # Each script line from will be in a collapsible section in the job output
     # and show the duration of each line.
     FF_SCRIPT_SECTIONS: 1
+    # The project has a fairly fat GIT repo so we try and avoid bringing in 
things
+    # we don't need. The --filter options avoid blobs and tree references we 
aren't going to use
+    # and we also avoid fetching tags.
+    GIT_FETCH_EXTRA_FLAGS: --filter=blob:none --filter=tree:0 --no-tags --prune
 
   interruptible: true
 
diff --git a/.gitlab-ci.d/buildtest-template.yml 
b/.gitlab-ci.d/buildtest-template.yml
index 4fbfeb6667..22045add80 100644
--- a/.gitlab-ci.d/buildtest-template.yml
+++ b/.gitlab-ci.d/buildtest-template.yml
@@ -14,6 +14,7 @@
     - export CCACHE_DIR="$CCACHE_BASEDIR/ccache"
     - export CCACHE_MAXSIZE="500M"
     - export PATH="$CCACHE_WRAPPERSDIR:$PATH"
+    - du -sh .git
     - mkdir build
     - cd build
     - ccache --zero-stats
diff --git a/.gitlab-ci.d/buildtest.yml b/.gitlab-ci.d/buildtest.yml
index a1c030337b..def469a9dc 100644
--- a/.gitlab-ci.d/buildtest.yml
+++ b/.gitlab-ci.d/buildtest.yml
@@ -187,6 +187,8 @@ build-previous-qemu:
   variables:
     IMAGE: opensuse-leap
     TARGETS: x86_64-softmmu aarch64-softmmu
+    # Override the default flags as we need more to grab the old version
+    GIT_FETCH_EXTRA_FLAGS: --prune
   before_script:
     - export QEMU_PREV_VERSION="$(sed 's/\([0-9.]*\)\.[0-9]*/v\1.0/' VERSION)"
     - git remote add upstream https://gitlab.com/qemu-project/qemu
diff --git a/.gitlab-ci.d/windows.yml b/.gitlab-ci.d/windows.yml
index f116b8012d..f9da745042 100644
--- a/.gitlab-ci.d/windows.yml
+++ b/.gitlab-ci.d/windows.yml
@@ -28,6 +28,8 @@ msys2-64bit:
     # qTests don't run successfully with "--without-default-devices",
     # so let's exclude the qtests from CI for now.
     TEST_ARGS: --no-suite qtest
+    # The Windows git is a bit older so override the default
+    GIT_FETCH_EXTRA_FLAGS: --no-tags --prune
   artifacts:
     name: "$CI_JOB_NAME-$CI_COMMIT_REF_SLUG"
     expire_in: 7 days
-- 
2.39.2