Remove watchdog

This watchdog thread watching is currently unused and bugged in some
context, this PR remove any mention of it.

Ref #3828

Fixes #3830

docs/asciidoc/static/command-line-flags.asciidoc

@@ -18,11 +18,6 @@ Logstash has the following flags. You can use the `--help` flag to display this
 -w, --filterworkers COUNT
  Sets the number of filter workers to run (default: 1)
 
---watchdog-timeout TIMEOUT
- Set watchdog timeout value in seconds. Default is 10. This timeout is used to detect
- stuck filters; stuck filters usually symptoms of bugs. When a filter takes longer than 
- TIMEOUT seconds, it will cause Logstash to abort.
-
 -l, --log FILE
  Log to a given path. Default is to log to stdout
 

docs/flags.md

@@ -20,8 +20,6 @@ default. If no output is specified, 'stdout { debug => true }}' is
 default. </dd>
 <dt> -w, --filterworkers COUNT </dt>
 <dd> Run COUNT filter workers (default: 1) </dd>
-<dt> --watchdog-timeout TIMEOUT </dt>
-<dd> Set watchdog timeout value in seconds. Default is 10.</dd>
 <dt> -l, --log FILE </dt>
 <dd> Log to a given path. Default is to log to stdout </dd>
 <dt> --verbose </dt>

lib/logstash/agent.rb

@@ -23,10 +23,6 @@ class LogStash::Agent < Clamp::Command
     I18n.t("logstash.agent.flag.filterworkers"),
     :attribute_name => :filter_workers, :default => 1, &:to_i
 
-  option "--watchdog-timeout", "SECONDS",
-    I18n.t("logstash.agent.flag.watchdog-timeout"),
-    :default => 10, &:to_f
-
   option ["-l", "--log"], "FILE",
     I18n.t("logstash.agent.flag.log"),
     :attribute_name => :log_file

lib/logstash/plugin.rb

@@ -97,18 +97,6 @@ class LogStash::Plugin
     return "#{self.class.name}: #{@params}"
   end
 
-  protected
-  def update_watchdog(state)
-    Thread.current[:watchdog] = Time.now
-    Thread.current[:watchdog_state] = state
-  end
-
-  protected
-  def clear_watchdog
-    Thread.current[:watchdog] = nil
-    Thread.current[:watchdog_state] = nil
-  end
-
   public
   def inspect
     if !@params.nil?

lib/logstash/threadwatchdog.rb

@@ -1,37 +0,0 @@
-# encoding: utf-8
-require "logstash/namespace"
-require "logstash/logging"
-
-class LogStash::ThreadWatchdog
-  attr_accessor :logger
-  attr_accessor :threads
-
-  class TimeoutError < StandardError; end
-
-  public
-  def initialize(threads, watchdog_timeout=10)
-    @threads = threads
-    @watchdog_timeout = watchdog_timeout
-  end # def initialize
-
-  public
-  def watch
-    while sleep(1)
-      cutoff = Time.now - @watchdog_timeout
-      @threads.each do |t|
-        watchdog = t[:watchdog]
-        if watchdog and watchdog <= cutoff
-          age = Time.now - watchdog
-          @logger.fatal("thread watchdog timeout",
-                        :thread => t,
-                        :backtrace => t.backtrace,
-                        :thread_watchdog => watchdog,
-                        :age => age,
-                        :cutoff => @watchdog_timeout,
-                        :state => t[:watchdog_state])
-          raise TimeoutError, "watchdog timeout"
-        end
-      end
-    end
-  end # def watch
-end # class LogStash::ThreadWatchdog

locales/en.yml

@@ -153,12 +153,6 @@ en:
           Check configuration for valid syntax and then exit.
         filterworkers: |+
           Sets the number of filter workers to run.
-        watchdog-timeout: |+
-          Set the filter watchdog timeout (in seconds).
-          This timeout is used to detect stuck filters;
-          stuck filters usually symptoms of bugs.
-          When a filter takes longer than TIMEOUT
-          seconds, it will cause logstash to abort.
         log: |+
           Write logstash internal logs to the given
           file. Without this flag, logstash will emit