Class: ServerMetrics::Processes::Process

Inherits:
Object
  • Object
show all
Defined in:
lib/server_metrics/collectors/processes.rb

Overview

a thin wrapper around Sys:ProcTable’s ProcTableStruct. We’re using it to add some fields and behavior. Beyond what we’re adding, it just passes through to its instance of ProcTableStruct

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(proctable_struct) ⇒ Process

Returns a new instance of Process.



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# File 'lib/server_metrics/collectors/processes.rb', line 164

def initialize(proctable_struct)
  @pts=proctable_struct
  @recent_cpu = 0
end

Instance Attribute Details

#recent_cpu ⇒ Object

used to store the calculation of CPU since last sample



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# File 'lib/server_metrics/collectors/processes.rb', line 163

def recent_cpu
  @recent_cpu
end

#recent_cpu_percentage ⇒ Object

used to store the calculation of CPU since last sample



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# File 'lib/server_metrics/collectors/processes.rb', line 163

def recent_cpu_percentage
  @recent_cpu_percentage
end

Instance Method Details

#cmdline ⇒ Object 



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# File 'lib/server_metrics/collectors/processes.rb', line 207

def cmdline
  @pts.cmdline
end

#combined_cpu ⇒ Object 



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# File 'lib/server_metrics/collectors/processes.rb', line 191

def combined_cpu
  # best thread I've seen on cutime vs utime & cstime vs stime: https://www.ruby-forum.com/topic/93176
  # * cutime and cstime include CPUusage of child processes
  # * utime and stime don't include CPU usage of child processes
  (utime || 0) + (stime || 0)  # utime and stime aren't available on mac. Result is %cpu is 0 on mac.
end

#comm ⇒ Object 



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# File 'lib/server_metrics/collectors/processes.rb', line 203

def comm
  @comm ||= @pts.comm
end

#has?(method_name) ⇒ Boolean

because apparently respond_to doesn’t work through method_missing

Returns:

  • (Boolean) 


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# File 'lib/server_metrics/collectors/processes.rb', line 170

def has?(method_name)
  @pts.respond_to?(method_name)
end

#pid ⇒ Object

For better performance, not using #method_missing to just pass these off to ProcTable::Struct.



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# File 'lib/server_metrics/collectors/processes.rb', line 199

def pid
  @pts.pid
end

#ppid ⇒ Object 



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# File 'lib/server_metrics/collectors/processes.rb', line 211

def ppid
  @pts.ppid
end

#rss ⇒ Object 



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# File 'lib/server_metrics/collectors/processes.rb', line 223

def rss
  @pts.rss
end

#set_recent_cpu(last_cpu, elapsed_jiffies, num_processors) ⇒ Object 



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# File 'lib/server_metrics/collectors/processes.rb', line 174

def set_recent_cpu(last_cpu,elapsed_jiffies,num_processors)
  if last_cpu
    self.recent_cpu = combined_cpu - last_cpu
  else
    self.recent_cpu = combined_cpu # this process wasn't around last time, so just use the cumulative CPU time for its existence so far
  end
  # a) self.recent_cpu / elapsed_jiffies = the amount of CPU time this process has taken divided by the total "time slots" the CPU has available
  # b) * 100 ... this turns it into a percentage
  # b) / num_processors ... this normalizes for the the number of processors in the system, so it reflects the amount of CPU power avaiable as a whole
  self.recent_cpu_percentage = ((recent_cpu.to_f / elapsed_jiffies.to_f ) * 100.0) / num_processors.to_f
end

#stime ⇒ Object 



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# File 'lib/server_metrics/collectors/processes.rb', line 219

def stime
  @pts.stime
end

#utime ⇒ Object 



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# File 'lib/server_metrics/collectors/processes.rb', line 215

def utime
  @pts.utime
end