| # Coordinator | |
| Prototype for a process/library-based dora-rs implementation, instead of framework-based. The idea is that each operator is compiled as a separate executable. The `dora-coordinator` runtime is responsible for reading the dataflow descriptor file and launching the operators accordingly. The operators use a common library called `dora-api`, which implements the communication layer based on zenoh. | |
| This approach has the following advantages: | |
| - Less overhead | |
| - No data transfer between a runtime and the operator | |
| - The compiler can inline and optimize the full process | |
| - More flexibility | |
| - Operators can be sync or async | |
| - They can decide how many threads and which execution model they use | |
| - The OS ensures fair share of resources (e.g. CPU time) -> no need to cooperate with other operators | |
| - Operators get all inputs immediately -> no need for input rules | |
| - Keeping local state is easily possible | |
| - Separate address spaces | |
| - The operators are isolated from each other. | |
| There are drawbacks too, for example: | |
| - Less control | |
| - Processes run independently -> need to cooperate with the runtime, e.g. on stop signals | |
| - Operator migration is more difficult | |
| - Operators are always isolated | |
| - No way of using in-memory channels | |
| - Local sockets and shared memory should be still possible | |