cloud8421/erlangpl

Getting started

The Erlang Performance Lab tool (erlangpl for short) can be started using escript or as a regular Erlang release.

For building UI you have to have node, yarn and elm-lang installed. Be aware that building UI can take some time. It takes around 1 minute on stock MacBook 2015 plus dependencies download for the first time. Second time dependencies will be cached.

$ git clone --recursive git@github.com:erlanglab/erlangpl.git
$ cd erlangpl
$ make rebar
$ make build-ui
$ make
$ ./bootstrap

Running erlangpl script

The erlangpl shell script is a self-contained escript, which can be started from a command line as long as you have Erlang/OTP installed.

$ ./erlangpl -h

Usage: erlangpl [-n <node>] [-c <cookie>] [-p <plugin>] [-h]
                [-v <verbose>] [-P <port>] [-V] [-s <sname>] [-l <name>]

  -n, --node     Monitored node name
  -c, --cookie   Overwrite ~/.erlang.cookie
  -p, --plugin   Path to plugins
  -h, --help     Show the program options
  -v, --verbose  Verbosity level (-v, -vv, -vvv)
  -P, --port     HTTP and WS port number
  -V, --version  Show version information
  -s, --sname    Start with a shortname
  -l, --name     Start with a longname, default erlangpl@127.0.0.1

$ ./erlangpl -n testnode@127.0.0.1 -c YOURCOOKIE

Once started, try visiting http://localhost:8000/

Examples

Connecting to an Elixir iex session

$ iex --name foo@127.0.0.1 -S mix

$ ./erlangpl --node foo@127.0.0.1

Mnesia cluster

You can generate messages between nodes by querying a distributed database Mnesia.

To setup a Mnesia cluster, start several Erlang nodes with unique names e.g. a@, b@, c@, etc. and start the database on all of them:

erl -name a@127.0.0.1
(a@127.0.0.1)1> mnesia:start().

Then create a test_table and configure it to be replicated on all nodes:

(a@127.0.0.1)2> mnesia:change_config(extra_db_nodes, ['b@127.0.0.1']).
(a@127.0.0.1)3> mnesia:change_config(extra_db_nodes, ['c@127.0.0.1']).
(a@127.0.0.1)4> mnesia:change_config(extra_db_nodes, ['d@127.0.0.1']).
(a@127.0.0.1)5> mnesia:create_table(test_table, []).
(a@127.0.0.1)6> [mnesia:add_table_copy(test_table, Node, ram_copies) || Node <- nodes()].

Here are some behaviours you can test:

[begin mnesia:transaction(fun() -> mnesia:write({test_table, Key, "value"}) end), timer:sleep(10) end || Key <- lists:seq(1,2000)].
[begin mnesia:sync_dirty(fun() -> mnesia:write({test_table, Key, "value"}) end), timer:sleep(10) end || Key <- lists:seq(1,2000)].
[begin mnesia:dirty_write({test_table, Key, "value"}), timer:sleep(10) end || Key <- lists:seq(1,2000)].

Videos from those experiments were posted on YouTube

Running development release

You can also start the tool as a regular Erlang release and connect to its console to debug the tool itself.

$ make
$ rebar -f generate
$ ./rel/erlangpl/bin/erlangpl console node=testnode@127.0.0.1 cookie=YOURCOOKIE

Have fun!

cloud8421 / erlangpl