ManageIQ MiqServer mem log initializer patch

miq_server_mem_log_patch.local.rb

# Make sure the normal MiqServer is autoloaded before monkey patching it
MiqServer

require 'objspace'

class MiqServer < ApplicationRecord
  alias _old_monitor_poll monitor_poll

  def monitor_poll
    begin
      @memory_log_diagnostic_count  ||= 0
      @memory_dump_diagnostic_count ||= 0
      @memory_log_diagnostic_count   += 1
      @memory_dump_diagnostic_count  += 1

      # Log every minute if monitor poll, assuming is set to 5.seconds
      if @memory_log_diagnostic_count % 12 == 0
        @memory_log_diagnostic_count = 0

        mem_info = Sys::ProcTable::Smaps.new(Process.pid, MiqSystem.readfile_async("/proc/#{Process.pid}/smaps"))

        # types = Hash.new { |h, k| h[k] = 0 }
        # ObjectSpace.each_object do |obj|
        #   types[obj.class.name] += 1
        # end.sort_by { |_k, v| -v }.take(50)

        _log.info "Memory Info XXXX => {"                                 \
                  "RSS: #{mem_info.rss}, "                                \
                  "PSS: #{mem_info.pss}, "                                \
                  "thread_count: #{Thread.list.length}, "                 \
                  "gc_stats: #{GC.stat.inspect}, "                        \
                  "objspace_count: #{ObjectSpace.count_objects.inspect}}"
        # _log.info("Ruby Object Usage: #{types.inspect}")
      end

      # log every 3 hours, assuming server is set to monitor poll every 5.seconds
      if @memory_dump_diagnostic_count % 2160 == 0
        @memory_dump_diagnostic_count = 0
        io = File.open("#{Rails.root}/tmp/miq_server_#{Time.now.to_i}_#{Process.pid}.dump", "w")
        ObjectSpace.dump_all(output: io)
        io.close
      end
    rescue => e
      # no-op if we have an error
      _log.info "XXXX ERR:  #{e.message}"
    end

    _old_monitor_poll
  end
end