If I run the flow.run block it seems to miss the cache every time... I'm v confused!

Welcome back! Whenever you run Prefect without a backend, the cache is stored in

prefect.context

. I believe that your call to

with prefect.context():

is effectively clearing the cache between runs

Thanks @Chris White - that did it. I was actually using the context for something but removed it for clarity. So this means that the cache stays around as long as the with block (which is a single run/gets cleared out every time)?

For sure! For your first question: - the cache lives in

prefect.context['caches']

, so if you clear your context the cache will disappear; if you removed the

with prefect.context():

block then you shouldn’t need to worry about the cache disappearing unexpectedly - for the backend, sounds like you figured it out but to provide some more color: Prefect Core alone maintains state only as long as the Python process running your Flow. We have various options for how to run flows in a more stateful way (which includes how task caching is handled!), one of which is Prefect Server (our open source offering) — if you don’t want to deal with setting up the database, services, etc. Prefect Cloud is essentially a managed version of server (with more bells and whistles, e.g., authentication / user management / etc.). Note also that Cloud is designed to keep your code and data private (see, e..g, https://medium.com/the-prefect-blog/the-prefect-hybrid-model-1b70c7fd296) For the best caching experience, I do recommend using one of our backends

got it, makes sense thank you

anytime anytime - let us know if you have any issues configuring server and / or getting caching working properly 👍

and one last thing: i noticed that prefect.context.today is in UTC not local

Haha yea, we found that using local timezones caused more confusion when migrating flows around from local -> production systems, so for consistency we keep everything in UTC

got it - ok. thanks!

anytime anytime, that’s what we’re here for