feat: symlink cached runner instead of copy #25
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- this should (sometimes dramatically) improve boot times if cache runner image is used
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Generally speaking as long as symlink targets are absolute paths, it does not matter if the symlink points to a different filesystem. Hard links will complain, but symlinks are just pointers. The |
| @@ -126,8 +126,8 @@ if [ -z "$CACHED_RUNNER" ];then | |||
| sudo ./bin/installdependencies.sh || fail "failed to install dependencies" | |||
| else | |||
| sendStatus "using cached runner found in $CACHED_RUNNER" | |||
| sudo cp -a "$CACHED_RUNNER" "/home/{{ .RunnerUsername }}/actions-runner" | |||
| sudo chown {{ .RunnerUsername }}:{{ .RunnerGroup }} -R "/home/{{ .RunnerUsername }}/actions-runner" || fail "failed to change owner" | |||
| ln -s "$CACHED_RUNNER"/actions-runner "/home/{{ .RunnerUsername}}/actions-runner" || fail "failed to create symlink" | |||
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You can quote the entire path:
ln -s "$CACHED_RUNNER/actions-runner" "/home/{{ .RunnerUsername}}/actions-runner" || fail "failed to create symlink"Variables cannot have slashes in them and the shell does the right thing.
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.. this change is very much relevant for us since it reduces our azure VM boot times quite significantly. However, we will need some more tweaks and changes, so I will close this one for now and create a new one once we're done.
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I wasn't suggesting to not add the change. It was just a nit which can be ignored. The change looked ok. Feel free to reopen when ready.
This should (sometimes dramatically) improve boot times if cache runner image is used.
We currently see that copying those ~500 MB takes around 3 Minutes during boot .. I don't know why it's that slow, and later the disk IO speed seems to be much better, but anyway we could skip that copy step all together.
The only issue is see is if /home is mounted on a different disk than /opt , in this case the symlink would probably not be what you would want. Do you think that is an issue? Am I missing other problems with that?