If I understand correctly,

@dynamic

is a workflow whose DAG is created during runtime (unlike

@workflow

whose DAG is created during compile time), which makes it more flexible. So my question is, what are the downsides of

@dynamic

compared to a static

@workflow

? Why aren’t all flyte workflows

@dynamic

(kind of like how all PyTorch computational graphs are by default dynamic)? Are there meaningful performance penalties to using

@dynamic

?

You don't get the safety of

@workflow

(compiled before registration). Dynamics being compiled at runtime means you can run into runtime issues that would've been caught by compiling the workflow (from my experience)

Right - but wouldn’t that be caught during local testing?

For the most part, yes. There's also the overhead of storing the entire DAG in the head dynamic node. I love dynamics, but have had issues with scale (when running 1,000s of tasks in a dynamic)

Ah ok, this was what I wanted to know - if there are tradeoff in terms of performance I need to worry about since I don’t understand the internals very well

We have thousands of samples, each sample can have 50GB+ of data, so we run at least 1 task per sample, leading to thousands of tasks!

Dynamic from a scale pov should behave similar to static, but you won’t be able to see the workflow before runtime

@freezing-airport-6809 thanks - but why is caching limited?

You can generate a task, how can Flyte know if the generated task is similar to previous

Couldn’t you technically compare the code at runtime instead of compile time to see if it is cached? I guess that’s easier said than done?

You can generate a task, how can Flyte know if the generated task is similar to previous

Can you comment on how this is done at the workflow level compared to dynamics? I thought caching was just interface/inputs/cache_version, which you'd have for both workflows and dynamics