orta / ping

A Heroku app to measure latency from client to the server

ping

A Heroku app to measure latency from client to the server

Usage

Deploy and open the top page of the app.

Via Heroku button

Click the Deloy to Heroku button, then migrate the database, and scale the worker:

$ heroku run rake db:migrate
$ heroku ps:scale worker=1

Schedule a task, say hourly, on Heroku Scheduler to sweep database for delayed execution of geocoding locations and measuring distances

rake locations:geocode ping_results:measure_distance

Via CLI

Alternatively, create an app on Heroku (or somewhere else), push, and provision add-ons:

$ heroku create <app-name>
$ heroku addons:create heroku-postgresql
$ heroku addons:create heroku-redis
$ heroku addons:create scheduler
$ git push heroku master

Migrate the database, and scale - one or more web and worker are needed:

$ heroku run rake db:migrate
$ heroku ps:scale web=1 worker=1

Schedule a task, say hourly, on Heroku Scheduler to sweep database for delayed execution of geocoding locations and measuring distances

rake locations:geocode ping_results:measure_distance

Debugging

Set APP_STATUS config var to staging for database access through the app.

Measurement

This program measures time needed to receive response for a HEAD request to one of its static assets. See the Javascript code for details.

The time measured shuold be for a round trip of packets between the client and the server. A tcpudmp shows something like below for each ping.

08:11:30.340923 IP misoan.51404 > ec2-54-243-156-39.compute-1.amazonaws.com.http: Flags [P.], seq 2347:3100, ack 2835, win 296, length 753
08:11:30.477844 IP ec2-54-243-156-39.compute-1.amazonaws.com.http > misoan.51404: Flags [P.], seq 2835:3052, ack 3100, win 96, length 217
08:11:30.477929 IP misoan.51404 > ec2-54-243-156-39.compute-1.amazonaws.com.http: Flags [.], ack 3052, win 314, length 0

Samples

• http://ping-us.herokuapp.com/
• http://ping-eu.herokuapp.com/
• http://ping-tokyo.herokuapp.com/

Other settings

Verification with loader.io

heroku config:set LOADERIO_VERIFICATION_TOKEN=loaderio-0123456789abcdef
heroku config:set LOADERIO_VERIFICATION_FILENAME=loaderio-0123456789abcdef