Hi all, I need help on understanding supervisor role in “ordinary” web architecture. I’m thinking the data flow will be like the following (notice the plurals): client → Load Balancer (LB) → elixir apps → workers or client → LB → elixir apps → supervisor → workers or client → LB → elixi…

The supervisor doesn’t do anything to your request. It just sits there and restart crashed processes.

so, supervisor doesn’t manages child node process at all?

Supervision trees is how you impose structure to your Erlang programs. They start with a simple concept, a supervisor, whose only job is to start processes, look at them, and restart them when they fail. By the way, supervisor are one of the core components of ‘OTP’, the general development framewo…

Usually it only managed static and longrunning processes, not such that are only spawned to handle a single request/workunit/connection or similar.

yes, but that article doesn’t mention supervisor’s relationship with “non OTP system” like the LB and MQ.

Supervisor is an OTP concept. The load balancing between nodes is the responsibility of the BEAM. RabbitMQ is an OTP application (unless you are talking about the BEAM process mailboxes - the mailbox is an integral part of any BEAM process while the BEAM handles the details of message routing betwee…

Is your question about Erlang supervisors, or the abstract idea of a supervisor in general? Assuming the first, in your example, supervisors are internal to the Elixir app (and the message queue, if you’re using rabbitmq). They have nothing to do with load balancing, etc. It’s just a way of organiz…

The BEAM spreads processes on schedulers within a single node. It doesn’t load balance between nodes.

RIght - got carried away there - the BEAM distributes the processes across the all the cores available to the node. Documentation: Frequently Asked Questions In distributed computer systems, load balancing is the act of spreading incoming traffic across all computers that can perform a…

Understanding supervisor

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peerreynders June 18, 2017, 11:06pm 10

RIght - got carried away there - the BEAM distributes the processes across the all the cores available to the node.