Module: MonitorServers
- Defined in:
- lib/capistrano/ext/monitor.rb
Constant Summary collapse
- LONG_TIME_FORMAT =
"%Y-%m-%d %H:%M:%S"
- SHORT_TIME_FORMAT =
"%H:%M:%S"
Instance Method Summary collapse
-
#date_column(operation, *args) ⇒ Object
A helper method for encapsulating the behavior of the date/time column in a report.
-
#headers(*args) ⇒ Object
A helper method for formatting table headers in a report.
-
#load(options = {}) ⇒ Object
Monitor the load of the servers tied to the current task.
- #put_asset(name, to) ⇒ Object
-
#remote_env(value) ⇒ Object
Get a value from the remote environment.
-
#requests_per_second(*logs) ⇒ Object
Monitor the number of requests per second being logged on the various servers.
Instance Method Details
#date_column(operation, *args) ⇒ Object
A helper method for encapsulating the behavior of the date/time column in a report.
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 |
# File 'lib/capistrano/ext/monitor.rb', line 10 def date_column(operation, *args) case operation when :init { :width => Time.now.strftime(LONG_TIME_FORMAT).length, :last => nil, :rows => 0 } when :show state = args.first now = Time.now date = now.strftime( (state[:rows] % 10 == 0 || now.day != state[:last].day) ? LONG_TIME_FORMAT : SHORT_TIME_FORMAT) state[:last] = now state[:rows] += 1 "%*s" % [state[:width], date] else raise "unknown operation #{operation.inspect}" end end |
#headers(*args) ⇒ Object
A helper method for formatting table headers in a report.
31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 |
# File 'lib/capistrano/ext/monitor.rb', line 31 def headers(*args) 0.step(args.length-1, 2) do |n| header = args[n] size = args[n+1] if header == "-" || header == " " print header * size, " " else print header padding = size - header.length - 1 print " ", "-" * padding if padding > 0 print " " end end puts end |
#load(options = {}) ⇒ Object
Monitor the load of the servers tied to the current task.
58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 |
# File 'lib/capistrano/ext/monitor.rb', line 58 def load(={}) servers = current_task.servers.sort names = servers.map { |s| s.match(/^(\w+)/)[1] } time = date_column(:init) load_column_width = "0.00".length * 3 + 2 puts "connecting..." connect! parser = Proc.new { |text| text.match(/averages: (.*)$/)[1].split(/, /) } delay = ([:delay] || 30).to_i running = true trap("INT") { running = false; puts "[stopping]" } # THE HEADER header = Proc.new do puts headers("-", time[:width], *names.map { |n| [n, load_column_width] }.flatten) end while running uptimes = {} run "uptime" do |ch, stream, data| raise "error: #{data}" if stream == :err uptimes[ch[:host]] = parser[data.strip] end # redisplay the header every 40 rows header.call if time[:rows] % 40 == 0 print(date_column(:show, time), " ") servers.each { |server| print(uptimes[server].join("/"), " ") } puts # sleep this way, so that CTRL-C works immediately delay.times { sleep 1; break unless running } end end |
#put_asset(name, to) ⇒ Object
225 226 227 |
# File 'lib/capistrano/ext/monitor.rb', line 225 def put_asset(name, to) put(File.read("#{File.dirname(__FILE__)}/assets/#{name}"), to) end |
#remote_env(value) ⇒ Object
Get a value from the remote environment
48 49 50 51 52 53 54 55 |
# File 'lib/capistrano/ext/monitor.rb', line 48 def remote_env(value) result = "" run("echo $#{value}", :once => true) do |ch, stream, data| raise "could not get environment variable #{value}: #{data}" if stream == :err result << data end result.chomp end |
#requests_per_second(*logs) ⇒ Object
Monitor the number of requests per second being logged on the various servers.
100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 |
# File 'lib/capistrano/ext/monitor.rb', line 100 def requests_per_second(*logs) # extract our configurable options from the arguments = logs.last.is_a?(Hash) ? logs.pop : {} request_pattern = [:request_pattern] || "Completed in [0-9]" sample_size = [:sample_size] || 5 stats_to_show = [:stats] || [0, 1, 5, 15] num_format = [:format] || "%4.1f" # set up the date column formatter, and get the list of servers time = date_column(:init) servers = current_task.servers.sort # initialize various helper variables we'll be using mutex = Mutex.new count = Hash.new(0) running = false channels = {} windows = Hash.new { |h,k| h[k] = { 1 => [], # last 1 minute 5 => [], # last 5 minutes 15 => [] # last 15 minutes } } minute_1 = 60 / sample_size minute_5 = 300 / sample_size minute_15 = 900 / sample_size # store our helper script on the servers. This script reduces the amount # of traffic caused by tailing busy logs across the network, and also reduces # the amount of work the client has to do. script = "#{remote_env("HOME")}/x-request-counter.rb" put_asset "request-counter.rb", script # set up (but don't start) the runner thread, which accumulates request # counts from the servers. runner = Thread.new do Thread.stop running = true run("echo 0 && tail -F #{logs.join(" ")} | ruby #{script} '#{request_pattern}'") do |ch, stream, out| channels[ch[:host]] ||= ch puts "#{ch[:host]}: #{out}" and break if stream == :err mutex.synchronize { count[ch[:host]] += out.to_i } end running = false end # let the runner thread get started runner.wakeup sleep 0.01 while !running # trap interrupt for graceful shutdown trap("INT") { puts "[stopping]"; channels.values.each { |ch| ch.close; ch[:status] = 0 } } # compute the stuff we need to know for displaying the header num_len = (num_format % 1).length column_width = num_len * (servers.length + 1) + servers.length abbvs = servers.map { |server| server.match(/^(\w+)/)[1][0,num_len] } col_header = abbvs.map { |v| "%-*s" % [num_len, v] }.join("/") # write both rows of the header stat_columns = stats_to_show.map { |n| case n when 0 then "#{sample_size} sec" when 1 then "1 min" when 5 then "5 min" when 15 then "15 min" else raise "unknown statistic #{n.inspect}" end } header = Proc.new do puts headers(" ", time[:width], *stat_columns.map { |v| [v, column_width] }.flatten) headers("-", time[:width], *([col_header, column_width] * stats_to_show.length)) end while running # sleep for the specified sample size (5s by default) (sample_size * 2).times { sleep(0.5); break unless running } break unless running # lock the counters and compute our stats at this point in time mutex.synchronize do totals = Hash.new { |h,k| h[k] = Hash.new(0) } # for each server... count.each do |k,c| # push the latest sample onto the tracking queues windows[k][1] = windows[k][1].push(count[k]).last(minute_1) windows[k][5] = windows[k][5].push(count[k]).last(minute_5) windows[k][15] = windows[k][15].push(count[k]).last(minute_15) # compute the stats for this server (k) totals[k][0] = count[k].to_f / sample_size totals[k][1] = windows[k][1].inject(0) { |n,i| n + i } / (windows[k][1].length * sample_size).to_f totals[k][5] = windows[k][5].inject(0) { |n,i| n + i } / (windows[k][5].length * sample_size).to_f totals[k][15] = windows[k][15].inject(0) { |n,i| n + i } / (windows[k][15].length * sample_size).to_f # add those stats to the totals per category totals[:total][0] += totals[k][0] totals[:total][1] += totals[k][1] totals[:total][5] += totals[k][5] totals[:total][15] += totals[k][15] end # redisplay the header every 40 rows header.call if time[:rows] % 40 == 0 # show the stats print(date_column(:show, time)) stats_to_show.each do |stat| print " " servers.each { |server| print "#{num_format}/" % totals[server][stat] } print(num_format % totals[:total][stat]) end puts # reset the sample counter count = Hash.new(0) end end end |