Usage Tips

Below are some ways to get the best experience with mozci.

Caching Results

Gathering the requisite data can sometimes be very expensive. Analyzing many pushes at once can take hours or even days. Luckily, mozci uses a caching mechanism so once a result is computed once, it won’t be re-computed (even between runs). See the linked docs for more details, but a basic file system cache can be set up by modifying ~/.config/mozci/config.toml and adding the following:

[mozci.cache]
retention = 10080  # minutes

[mozci.cache.stores]
file = { driver = "file", path = "/path/to/cache" }

Pre-seeding the Cache via Bugbug

There’s a service called bugbug that runs mozci against all of the pushes on autoland. This service uploads its cache on S3 for others to use. You can benefit by using this uploaded cache to “pre-seed” your own local cache, if you have the necessary scopes. To do so, add the following to your ~/.config/mozci/config.toml:

[mozci.cache]
serializer = "compressedpickle"

[mozci.cache.stores]
s3 = { driver = "s3", bucket = "communitytc-bugbug", prefix = "data/mozci_cache/" }