mpmiszczyk / recon_demo

Playground for recon, for practice and demos.

Recon Demo

WHAAAT

Recon-demo is an app built to demo some of recon's capabilities. It consists of 26 processes named and registered in gproc (using strings) as:

Alfa          November
Bravo         Oscar
Charlie       Papa
Delta         Quebec (woo!)
Echo          Romeo
Foxtrot       Sierra
Golf          Tango
Hotel         Uniform
India         Victor
Juliett       Whiskey
Kilo          Xray
Lima          Yankee
Mike          Zulu

Each of them will:

• have a non-deterministic behavior. Each run is different.
• have a TCP connection open and listening
• try to contact each other randomly
• have different levels of chattiness and activity (frequency, msg size)
• will randomly try to send messages over message passing or TCP
• log nothing
• have no particular debugging code in place
• TCP is handled by each process starting its own listen socket, spawning a connector, accepting the connection, having the connector hand over the connected port, and store all of that data in a table (or Gproc) somewhere. Peers can use that connect port to send data to the process, but can't read from it unless they're the owner. This allows to do TCP work where everybody sends using the same connection, and is to be used more as a way to simplify the whole request/response setup. UDP could have been done similarly.

Questions to Answer

• What's the system memory?
• Is the node's CPU loaded?
• Is any process mailbox overflowing?
• Which chatty process takes the most memory?
• Which chatty process is eating the most CPU?
• Which chatty process is consuming the most bandwidth?
• Which chatty process sends the most messages over TCP? The least?
• Can chatty processes message themselves? (can this work with registered names? Do I need to check the chattiest one and see if it messages itself?)
• If they send messages to themselves, can you make it so they can't without touching code? The opposite?
• Can you estimate the overall frequency at which messages are sent globally?

Building

Assumes you have rebar3 installed somewhere:

rebar3 release

Running

./_build/default/rel/recon_demo/bin/recon_demo