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.github/workflows/master.yml

@@ -882,6 +882,7 @@ jobs:
           fi
           sudo touch /var/run/job.in.progress
           rm -rf cleanup.sh install_cleanup.sh
+          # after this PR is merged, update URLs to get the scripts from github master
           wget https://storage.googleapis.com/minikube-ci-utils/cleanup.sh
           wget https://storage.googleapis.com/minikube-ci-utils/install_cleanup.sh
           chmod +x cleanup.sh install_cleanup.sh

.github/workflows/pr.yml

@@ -879,6 +879,7 @@ jobs:
           fi
           sudo touch /var/run/job.in.progress
           rm -rf cleanup.sh install_cleanup.sh
+          # after this PR is merged, update URLs to get the scripts from github master
           wget https://storage.googleapis.com/minikube-ci-utils/cleanup.sh
           wget https://storage.googleapis.com/minikube-ci-utils/install_cleanup.sh
           chmod +x cleanup.sh install_cleanup.sh

hack/gh_actions/cleanup.sh

@@ -19,6 +19,8 @@ REBOOT_MARK=/var/run/reboot.in.progress
 
 timeout=900 # 15 minutes
 
+# $PROGRESS_MARK file is touched when a new GitHub Actions job is started
+# check that no job was started in the last 15 minutes
 function check_running_job() {
   if [[ -f "$PROGRESS_MARK" ]]; then
     started=$(date -r "$PROGRESS_MARK" +%s)
@@ -35,6 +37,7 @@ function check_running_job() {
 
 check_running_job
 sudo touch "$REBOOT_MARK"
+# avoid race if a job was started between two lines above and recheck
 check_running_job
 
 echo "cleanup docker..."

hack/gh_actions/install_cleanup.sh

@@ -19,10 +19,12 @@ if [[ ! -f cleanup.sh ]]; then
   exit 1
 fi
 
+# update cron to run the cleanup script every hour
 if [ ! -f /etc/cron.hourly/cleanup.sh ]; then
-  sudo install cleanup.sh /etc/cron.hourly/cleanup || echo "FAILED TO INSTALL CLEANUP"
+  sudo install cleanup.sh /etc/cron.hourly/cleanup.sh || echo "FAILED TO INSTALL CLEANUP"
 fi
 
+# install a cron rule to remove /var/run/reboot.in.progress file immediately after reboot
 if (crontab -l 2>/dev/null | grep '@reboot rm -rf /var/run/reboot.in.progress'); then
   echo "reboot cron rule already installed"
   exit 0