StackTracy

Investigate and detect slow methods within the stack trace of your Ruby (optionally Sinatra) application

Introduction

StackTracy is created for simply investigating your stack trace for called methods and its corresponding duration. You can filter modules / classes / methods within the output tree.

The gem is partly written in C to reduce the application performance as minimal as possible.

Watch the "Using StackTracy within a small Sinatra application" screencast to see StackTracy in action!

Installation

Add `StackTracy` to your Gemfile

gem "stack_tracy"

Install the gem dependencies

$ bundle

Usage

Recording stack events

Using StackTracy is pretty straightforward. You can either start and stop stack events recording.

[1] pry(main)> StackTracy.start
[2] pry(main)> puts "testing"
[3] pry(main)> StackTracy.stop

Or you can use the stack_tracy convenience method which records stack events within the passed block.

[1] pry(main)> stack_tracy do
[1] pry(main)*   puts "testing"
[1] pry(main)* end

Reducing recorded stack events

As StackTracy records every call and return event, the resulted stack tree can get immense huge. Especially when dealing with complicated or extensive applications. If this is the case, I really recommend using following options which instructs StackTracy to reduce the recorded stack events.

It accepts an options Hash with at least one of the following keys:

:only - Only matching events will be recorded
:exclude - Matching events will be ignored

The value can be either a String (optionally whitespace-delimited) or an array of strings containing class and/or module names. You can use the wildcard (*) for matching classes and/or modules within that namespace.

Some examples

You can pass options as follows:

[1] pry(main)> StackTracy.start :only => ["Foo"]
[2] pry(main)> StackTracy.start :exclude => [:core]

When using the convenience method:

[3] pry(main)> stack_tracy(:only => "Foo") { puts "testing" }
[4] pry(main)> stack_tracy(:dump, {:only => "Foo*"}) { puts "testing" }
[5] pry(main)> stack_tracy(:open, {:exclude => ["Array", "Hash"]}) { puts "testing" }

Let's say that you have the following code:

class Foo
  class Bar; end
  module CandyBar; end
end

class FooBar; end

A couple of examples:

:only => "Foo" records Foo
:only => "Foo*" records Foo, Foo::Bar and Foo::CandyBar
:only => "Foo*", :exclude => "Foo::Bar" records Foo and Foo::CandyBar
:exclude => ["Foo*", "FooBar"] records everything except for Foo, Foo::Bar, Foo::CandyBar and FooBar
:only => "Foo* Kernel" records Foo, Foo::Bar, Foo::CandyBar and Kernel
:exclude => :core records everything except for Ruby core classes and modules (see stack_tracy.rb for more details)

Adding trace messages

Sometimes you want to add marks to the stack tree in order to recognize certain events. You can do this by adding trace messages with the String#tracy method:

[1] pry(main)> stack_tracy(:print) do
[1] pry(main)*   "Putting string".tracy
[1] pry(main)*   puts "Hello world!"
[1] pry(main)*   "Done putting string".tracy
[1] pry(main)* end
Hello world!
"Putting string" <0.000007>
Kernel#puts <0.000038>
   IO#puts <0.000034>
      IO#write <0.000017>
      IO#write <0.000009>
"Done putting string" <0.000003>
=> nil

You can also encapsulate trace messages by executing code within a block:

[1] pry(main)> stack_tracy(:print) do
[1] pry(main)*   "Doing things".tracy do
[1] pry(main)*     "" * 10
[1] pry(main)*     "Putting string".tracy do
[1] pry(main)*       puts "Hello world!"
[1] pry(main)*     end
[1] pry(main)*   end
[1] pry(main)* end
Hello world!
"Doing things" <0.000057>
   String#* <0.000003>
   "Putting string" <0.000043>
      Kernel#puts <0.000038>
         IO#puts <0.000033>
            IO#write <0.000017>
            IO#write <0.000009>
=> nil

Configure StackTracy

You can configure StackTracy regarding the default stack tree reduction behaviour, its dump directory and whether to include the source location when dumping recorded stack events:

StackTracy.config do |c|
  c.dump_dir             = "."                        #=> default: Dir::tmpdir
  c.dump_source_location = "."                        #=> default: false
  c.limit                = 1000                       #=> default: 7500
  c.threshold            = 0.005                      #=> default: 0.001
  c.messages_only        = true                       #=> default: false
  c.slows_only           = false                      #=> default: false
  c.only                 = "Foo*"                     #=> default: nil
  c.exclude              = %w(Foo::Bar Foo::CandyBar) #=> default: nil
end

As already mentioned, recorded stack traces can easily get very huge. So StackTracy will use the :limit and :threshold options when generating the HTML stack trace page (after having invoked StackTracy.open).

When the amount of calls within the stack trace exceeds the specified :limit, StackTracy will automatically filter out Ruby core classes and modules calls and it will also apply the :threshold option.

When applying the :threshold, calls with a duration below the :threshold will be folded at default within the stack tree which saves a lot of heavy browser rendering on page load as the 'child calls' will be rendered as comment. See this commit for more information.

As of version v0.1.5, StackTracy.open (and thus the CLI) is provided with the options :messages_only and :slows_only. When having set :messages_only to true, the stack tree will only include trace messages. If you have set :slows_only to true, then the stack tree will only include slow calls (duration > threshold) and trace messages.

Using recorded stack events

Once you have recorded stack events, you can call the following methods:

StackTracy.stack_trace - returns all recorded stack events (array of StackTracy::EventInfo instances)

[2] pry(main)> StackTracy.stack_trace.inspect
=> [
  #<StackTracy::EventInfo:0x0000010154b418 @event="c-call", @file="(pry)", @line=2, @singleton=false, @object=Kernel, @method="puts", @nsec=1344465432463251968>,
  #<StackTracy::EventInfo:0x0000010154b350 @event="c-call", @file="(pry)", @line=2, @singleton=false, @object=IO, @method="puts", @nsec=1344465432463272960>,
  #<StackTracy::EventInfo:0x0000010154b1c0 @event="c-call", @file="(pry)", @line=2, @singleton=false, @object=IO, @method="write", @nsec=1344465432463288064>,
  #<StackTracy::EventInfo:0x0000010154b0a8 @event="c-return", @file="(pry)", @line=2, @singleton=false, @object=IO, @method="write", @nsec=1344465432463331072>,
  #<StackTracy::EventInfo:0x0000010154af68 @event="c-call", @file="(pry)", @line=2, @singleton=false, @object=IO, @method="write", @nsec=1344465432463344896>,
  #<StackTracy::EventInfo:0x0000010154ae50 @event="c-return", @file="(pry)", @line=2, @singleton=false, @object=IO, @method="write", @nsec=1344465432463365888>,
  #<StackTracy::EventInfo:0x0000010154ad38 @event="c-return", @file="(pry)", @line=2, @singleton=false, @object=IO, @method="puts", @nsec=1344465432463378944>,
  #<StackTracy::EventInfo:0x0000010154ac20 @event="c-return", @file="(pry)", @line=2, @singleton=false, @object=Kernel, @method="puts", @nsec=1344465432463390976>]
]

StackTracy.select - returns (optionally filtered) recorded stack events for printing purposes (array of Hash instances)

[3] pry(main)> StackTracy.select.inspect
=> [
  {:event=>"c-call", :file=>"(pry)", :line=>2, :singleton=>false, :object=>Kernel, :method=>"puts", :nsec=>1344464282852728064, :call=>"Kernel#puts", :depth=>0, :duration=>0.000129024},
  {:event=>"c-call", :file=>"(pry)", :line=>2, :singleton=>false, :object=>IO, :method=>"puts", :nsec=>1344464282852748032, :call=>"IO#puts", :depth=>1, :duration=>9.7024e-05},
  {:event=>"c-call", :file=>"(pry)", :line=>2, :singleton=>false, :object=>IO, :method=>"write", :nsec=>1344464282852762112, :call=>"IO#write", :depth=>2, :duration=>3.4816e-05},
  {:event=>"c-call", :file=>"(pry)", :line=>2, :singleton=>false, :object=>IO, :method=>"write", :nsec=>1344464282852811008, :call=>"IO#write", :depth=>2, :duration=>2.0992e-05}
]
[4] pry(main)> StackTracy.select(%w(Kernel)).inspect
=> [
  {:event=>"c-call", :file=>"(pry)", :line=>2, :singleton=>false, :object=>Kernel, :method=>"puts", :nsec=>1344464282852728064, :call=>"Kernel#puts", :depth=>0, :duration=>0.000129024}
]
[5] pry(main)> StackTracy.select("Kernel IO#puts").inspect
=> [
  {:event=>"c-call", :file=>"(pry)", :line=>2, :singleton=>false, :object=>Kernel, :method=>"puts", :nsec=>1344464282852728064, :call=>"Kernel#puts", :depth=>0, :duration=>0.000129024},
  {:event=>"c-call", :file=>"(pry)", :line=>2, :singleton=>false, :object=>IO, :method=>"puts", :nsec=>1344464282852748032, :call=>"IO#puts", :depth=>1, :duration=>9.7024e-05}
]

StackTracy.print - prints (optionally filtered) recorded stack events as a tree

[6] pry(main)> StackTracy.print
Kernel#puts <0.000094>
   IO#puts <0.000069>
      IO#write <0.000018>
      IO#write <0.000016>
=> nil

Writing data to CSV files

You can dump (optionally filtered) recorded stack events to a CSV file.

[1] pry(main)> StackTracy.start
[2] pry(main)> puts "testing"
=> testing
[3] pry(main)> StackTracy.stop
[4] pry(main)> StackTracy.print
Kernel#puts <0.000121>
   IO#puts <0.000091>
      IO#write <0.000032>
      IO#write <0.000020>
=> nil
[5] pry(main)> StackTracy.dump "result.csv"
=> true

CSV sample file

This is what the contents of result.csv would look like:

event;;;singleton;object;method;nsec;call;depth;duration
c-call;;;false;Kernel;puts;1344466943040581120;Kernel#puts;0;0.000120832
c-call;;;false;IO;puts;1344466943040599040;IO#puts;1;9.1904e-05
c-call;;;false;IO;write;1344466943040613120;IO#write;2;3.2768e-05
c-call;;;false;IO;write;1344466943040658944;IO#write;2;1.9968e-05

When invoking StackTracy.dump "result.csv", true and thus including the source location:

event;file;line;singleton;object;method;nsec;call;depth;duration
c-call;(pry);2;false;Kernel;puts;1344466943040581120;Kernel#puts;0;0.000120832
c-call;(pry);2;false;IO;puts;1344466943040599040;IO#puts;1;9.1904e-05
c-call;(pry);2;false;IO;write;1344466943040613120;IO#write;2;3.2768e-05
c-call;(pry);2;false;IO;write;1344466943040658944;IO#write;2;1.9968e-05

Viewing stack events in your browser

You can easily view the dumped stack events within your browser by either calling the following within Ruby:

[1] pry(main)> StackTracy.open "some/dir/file.csv"

Your default browser will be launched in which the stack events will be displayed.

When passing no path, StackTracy will look for stack_events-<random generated postfix>.csv in either the default dump directory, the current directory or Dir::tmpdir and display it in the browser. When not found, it will display the last compiled stack tree when available:

[2] pry(main)> StackTracy.open

Using the CLI (command line interface)

Another way for viewing stack events in your browser is using the CLI tracy within the Terminal:

$ tracy             #=> let StackTracy auto-determine which file to display
$ tracy .           #=> display the last data file within the current directory
$ tracy foo/bar.csv #=> display foo/bar.csv

To get info about its options, type tracy help open:

$ tracy help open
Usage:
  tracy open [PATH]

Options:
  -l, [--limit=N]
  -t, [--threshold=N]
  -m, [--messages-only=MESSAGES_ONLY]
  -s, [--slows-only=SLOWS_ONLY]

Display StackTracy data within the browser (PATH is optional)

Kernel#stack_tracy

As already mentioned, there is a convenience method called stack_tracy convenience method. The following shows a couple variants with its equivalent "normal implementation".

Without passing an argument

Record stack events executed within a block:

[1] pry(main)> stack_tracy do
[1] pry(main)*   puts "testing"
[1] pry(main)* end

Its equivalent:

[1] pry(main)> StackTracy.start
[2] pry(main)> puts "testing"
[3] pry(main)> StackTracy.stop

Passing `:print`

Record stack events executed within a block and print the stack tree:

[1] pry(main)> stack_tracy :print do
[1] pry(main)*   puts "testing"
[1] pry(main)* end

Its equivalent:

[1] pry(main)> StackTracy.start
[2] pry(main)> puts "testing"
[3] pry(main)> StackTracy.stop
[4] pry(main)> StackTracy.print

Passing `:dump`

Record stack events executed within a block and write the obtained data to <default dump directory>/stack_events-<random generated postfix>.csv:

[1] pry(main)> stack_tracy :dump do
[1] pry(main)*   puts "testing"
[1] pry(main)* end

Its equivalent:

[1] pry(main)> StackTracy.start
[2] pry(main)> puts "testing"
[3] pry(main)> StackTracy.stop
[4] pry(main)> StackTracy.dump

Passing a target directory

Record stack events executed within a block and write the obtained data to <passed directory>/stack_events-<random generated postfix>.csv:

[1] pry(main)> stack_tracy Dir::tmpdir do
[1] pry(main)*   puts "testing"
[1] pry(main)* end

Its equivalent:

[1] pry(main)> StackTracy.start
[2] pry(main)> puts "testing"
[3] pry(main)> StackTracy.stop
[4] pry(main)> StackTracy.dump Dir::tmpdir

Passing a CSV file path

Record stack events executed within a block and write the obtained data to the passed file path:

[1] pry(main)> stack_tracy "some/file.csv" do
[1] pry(main)*   puts "testing"
[1] pry(main)* end

Its equivalent:

[1] pry(main)> StackTracy.start
[2] pry(main)> puts "testing"
[3] pry(main)> StackTracy.stop
[4] pry(main)> StackTracy.dump "some/file.csv"

Passing `:open`

Record stack events executed within a block and open the stack tree in your browser:

[1] pry(main)> stack_tracy :open do
[1] pry(main)*   puts "testing"
[1] pry(main)* end

Its equivalent:

[1] pry(main)> StackTracy.start
[2] pry(main)> puts "testing"
[3] pry(main)> StackTracy.stop
[4] pry(main)> StackTracy.dump do |file|
[4] pry(main)*   StackTracy.open file, true
[4] pry(main)* end

Hooking into Sinatra requests

You can easily hook StackTracy into Sinatra requests. This is a complete working example:

require "sinatra"
require "stack_tracy"

use StackTracy::Sinatra, :open

get "/" do
  "Hello world!"
end

Note: Make sure you have the sinatra and stack_tracy gems installed.

Open the Sinatra application in your browser at http://localhost:4567 and the complete stack tree will be displayed in your browser! ^^

You can also open http://localhost:4567/tracy afterwards by the way.

Taking more control

I can imagine that you don't want to hook into every Sinatra request. So you can pass a block which will be yielded before every request. The request will only be traced when the block does not return either false or nil:

use StackTracy::Sinatra do |path, params|
  path == "/" #=> only trace "http://localhost:4567"
end

Also, you can determine what StackTracy has to do after the request has finished. It resembles the invocation of stack_tracy. The following will dump every request into the current directory:

use StackTracy::Sinatra, "."

This will immediately open the stack tree in your default browser after every traced request:

use StackTracy::Sinatra, :open do |path, params|
  path == "/paul/engel" #=> only trace and open stack tree when opening "http://localhost:4567/paul/engel"
end

Reduce the stack tree and open it immediately:

use StackTracy::Sinatra, :open, :only => "Foo*"

Using the console

The StackTracy repo is provided with script/console which you can use for development / testing purposes.

Run the following command in your console:

$ script/console
Loading development environment (StackTracy 0.1.9)
[1] pry(main)> stack_tracy :print do
[1] pry(main)*   puts "testing"
[1] pry(main)* end
testing
Kernel#puts <0.000121>
   IO#puts <0.000091>
      IO#write <0.000032>
      IO#write <0.000020>
=> nil
[2] pry(main)>

Testing

Run the following command for testing:

$ rake

You can also run a single test file:

$ ruby test/unit/test_tracy.rb

TODO

Optimize C implementation performance when converting C data to Ruby objects within stack_tracy_stop
Improve stack tree reduction by checking on method level
Correct StackTracy::PRESETS regarding :active_record and :data_mapper
Easily hook into Rails requests?

Contact me

For support, remarks and requests, please mail me at paul.engel@holder.nl.

Credit

Two functions within the StackTracy C implementation are taken from ruby-prof.
The table sort within the Cumulatives tab is implemented with TinySort.
Being able to improve browser performance when loading heavy HTML stack trace pages using Ravi Raj's (@raviraj4u) blog post: http://ravirajsblog.blogspot.nl/2010/12/another-hack-to-render-heavy-html-pages.html

License

http://holder.nl - http://codehero.es - http://gettopup.com - http://github.com/archan937 - http://twitter.com/archan937 - paul.engel@holder.nl

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

stack_tracy

Runtime

StackTracy

Introduction

Installation

Add StackTracy to your Gemfile

Install the gem dependencies

Usage

Recording stack events

Reducing recorded stack events

Some examples

Adding trace messages

Configure StackTracy

Using recorded stack events

Writing data to CSV files

CSV sample file

Viewing stack events in your browser

Using the CLI (command line interface)

Kernel#stack_tracy

Without passing an argument

Passing :print

Passing :dump

Passing a target directory

Passing a CSV file path

Passing :open

Hooking into Sinatra requests

Taking more control

Using the console

Testing

TODO

Contact me

Credit

License

Add `StackTracy` to your Gemfile

Passing `:print`

Passing `:dump`

Passing `:open`