distributed 2021.10.0

Tracks the current state of workers, data, and computations.

Handles transitions between different task states. Notifies the Scheduler of changes by messaging passing through Queues, which the Scheduler listens to responds accordingly.

All events are handled quickly, in linear time with respect to their input (which is often of constant size) and generally within a millisecond. Additionally when Cythonized, this can be faster still. To accomplish this the scheduler tracks a lot of state. Every operation maintains the consistency of this state.

Users typically do not interact with Transitions directly. Instead users interact with the Client , which in turn engages the Scheduler affecting different transitions here under-the-hood. In the background Worker``s also engage with the ``Scheduler affecting these state transitions as well.

State

The Transitions object contains the following state variables. Each variable is listed along with what it stores and a brief description.

Underlying task state of dynamic scheduler

Examples

See :

Local connectivity graph

Hover to see nodes names; edges to Self not shown, Caped at 50 nodes.

Using a canvas is more power efficient and can get hundred of nodes ; but does not allow hyperlinks; , arrows or text (beyond on hover)

SVG is more flexible but power hungry; and does not scale well to 50 + nodes.

All aboves nodes referred to, (or are referred from) current nodes; Edges from Self to other have been omitted (or all nodes would be connected to the central node "self" which is not useful). Nodes are colored by the library they belong to, and scaled with the number of references pointing them


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