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287 points shadaj | 1 comments | | HN request time: 0.202s | source
1. kodablah ◴[] No.43197986[source]
> Just like the external-distribution model, arbitrary-location architectures often come with a performance cost. Durable execution systems typically snapshot their state to a persistent store between every step.

This is not true by most definitions of "snapshot". Most (all?) durable execution systems use event sourcing and therefore it's effectively an immutable event log. And it's only events that have external side effects enough to rebuild the state, not all state. While technically this is not free, it's much more optimal than the traditional definition of capturing and storing a "snapshot".

> But this simplicity comes at a significant cost: control. By letting the runtime decide how the code is distributed [...] we don’t want to give up: Explicit control over placement of logic on machines, with the ability to perform local, atomic computations

Not all durable execution systems require you to give this up completely. Temporal (disclaimer: my employer) allows grouping of logical work by task queue which many users use to pick locations of work, even so far as a task queue per physical resource which is very common for those wanting that explicit control. Also there are primitives for executing short, local operations within workflows assuming that's what is meant there.