dmpetrov
commented
6 years ago Hi @kskyten, thank you for your kind words about DVC.
You have an interesting scenario - like auto-ML. We designed DVC with this kind of scenarios in mind. Not all of our ideas were implemented in the first version (the current released version) - more scenarios are coming in the next version.
First, let's discuss how can we avoid your issue. By your current code you create cyclic dependencies with symlinks: data/res.txt version N --> data/res.txt version N-1 --> data/res.txt version (N-2) --> ... --> the current data/cache file. So, you are actually having a right symlink with the right version when you do git checkout PREV_COMMIT but it still points to the latest data/cache file.
To avoid the issue you should not write to an existing symlink file directly. I'd read the data file first, delete the file and increment it later. The git checkout will work properly. Do not forget dvc repro because dvc remove removes cache files by default.
mkdir myrepo_old/
cd myrepo_old/
git init
dvc init
dvc run echo "0" --stdout data/res.txt
cat data/res.txt
# 0 expected
# A single increment
VAL=`cat data/res.txt`
dvc remove data/res.txt # Keep cache. So, you won't need dvc repro
dvc run echo $(($VAL + 1)) --stdout data/res.txt
cat data/res.txt
# 1 excepted
# A batch increment
for num in {0..32}; do
VAL=`cat data/res.txt`
dvc remove data/res.txt
dvc run echo $(($VAL + 1)) --stdout data/res.txt
done
cat data/res.txt
# 34 expected
# Git checkout works!
git checkout HEAD~12 -b alpha_optimum
dvc repro
cat data/res.txt
# 28 expectedI'd appreciate if you could share more details. This will help us to support more scenarios.
- What is your goal in this step? Are you trying to find the optimum value for some metrics? Is the metric located in a different data file?
- Have you considered creating branches for each of the iterations? Like alpha_iter_0, .. alpha_iter_34.
Thank you for using DVC.
kskyten
yarikoptic
Thanks for making dvc. It looks really interesting.
I'm trying to use Bayesian optimization to optimize the hyperparameters of a model. This creates a cyclic dependency in the workflow. Executing
dvc run python code.pymultiple times with the following minimal example updates the state of the file 'data/res.txt', but reverting back to an older commit does not revert the changes. I think adding cyclic dependencies would be a useful feature to have. What kind of changes would be needed to add it?