nerf-herder

A companion service to mongod to keep long running queries from wrecking havoc

Nerf Herder

A companion service to mongod to keep long running queries from causing chaos. Every so often config.interval nerfHerder will poll mongo to find a list of current operations. nerfHerder will then loop through each operation and evaluate each rule in config.rules. Each λ rule has the operation set as the context this. The λ can due whatever logic it wants and then return a thruthy value. true means the nerf lives, false means the nerf dies, killOp will be called to kill it.

git clone git@github.com:thurmda/nerfHerder.git
npm install
npm test
nerfHerder -d MONGO_CONNECTION_STRING -f PATH_TO_CONFIG

example

nerfHerder -d mongodb://localhost:27017/local -f test/config/config.js
module.exports = {
"interval" : .3 * 1000, //Polling interval in miliseconds 
"rules" : [
            function(){/* 'Print op and let it live.' */ console.log(JSON.stringify(this)); return true;},
            function(){/*Kill everything over 2 secs! */ return (this.secs_running < 2);}
       ]
}

###ref http://www.youtube.com/watch?v=1f6Xc3PsOkc