Merge branch 'origin-3609-arv-run' into master closes #3609
[arvados.git] / services / api / script / crunch-dispatch.rb
index aa91d68aebda036a1a4792026e8a48ee960a3665..44ea396dc74e77cb497d968f4dde76d8f25f2004 100755 (executable)
@@ -1,5 +1,6 @@
 #!/usr/bin/env ruby
 
+require 'shellwords'
 include Process
 
 $options = {}
@@ -190,6 +191,23 @@ class Dispatcher
     nodelist
   end
 
+  def fail_job job, message
+    $stderr.puts "dispatch: #{job.uuid}: #{message}"
+    begin
+      Log.new(object_uuid: job.uuid,
+              event_type: 'dispatch',
+              owner_uuid: job.owner_uuid,
+              summary: message,
+              properties: {"text" => message}).save!
+    rescue
+      $stderr.puts "dispatch: log.create failed"
+    end
+    job.state = "Failed"
+    if not job.save
+      $stderr.puts "dispatch: job.save failed"
+    end
+  end
+
   def start_jobs
     @todo.each do |job|
       next if @running[job.uuid]
@@ -232,12 +250,24 @@ class Dispatcher
                          "GEM_PATH=#{ENV['GEM_PATH']}")
       end
 
-      job_auth = ApiClientAuthorization.
-        new(user: User.where('uuid=?', job.modified_by_user_uuid).first,
-            api_client_id: 0)
-      if not job_auth.save
-        $stderr.puts "dispatch: job_auth.save failed"
-        next
+      @authorizations ||= {}
+      if @authorizations[job.uuid] and
+          @authorizations[job.uuid].user.uuid != job.modified_by_user_uuid
+        # We already made a token for this job, but we need a new one
+        # because modified_by_user_uuid has changed (the job will run
+        # as a different user).
+        @authorizations[job.uuid].update_attributes expires_at: Time.now
+        @authorizations[job.uuid] = nil
+      end
+      if not @authorizations[job.uuid]
+        auth = ApiClientAuthorization.
+          new(user: User.where('uuid=?', job.modified_by_user_uuid).first,
+              api_client_id: 0)
+        if not auth.save
+          $stderr.puts "dispatch: auth.save failed"
+          next
+        end
+        @authorizations[job.uuid] = auth
       end
 
       crunch_job_bin = (ENV['CRUNCH_JOB_BIN'] || `which arv-crunch-job`.strip)
@@ -245,70 +275,76 @@ class Dispatcher
         raise "No CRUNCH_JOB_BIN env var, and crunch-job not in path."
       end
 
-      require 'shellwords'
-
       arvados_internal = Rails.configuration.git_internal_dir
       if not File.exists? arvados_internal
         $stderr.puts `mkdir -p #{arvados_internal.shellescape} && cd #{arvados_internal.shellescape} && git init --bare`
       end
 
-      repo_root = Rails.configuration.git_repositories_dir
-      src_repo = File.join(repo_root, job.repository + '.git')
-      if not File.exists? src_repo
-        src_repo = File.join(repo_root, job.repository, '.git')
+      git = "git --git-dir=#{arvados_internal.shellescape}"
+
+      # @fetched_commits[V]==true if we know commit V exists in the
+      # arvados_internal git repository.
+      @fetched_commits ||= {}
+      if !@fetched_commits[job.script_version]
+
+        repo_root = Rails.configuration.git_repositories_dir
+        src_repo = File.join(repo_root, job.repository + '.git')
         if not File.exists? src_repo
-          $stderr.puts "dispatch: No #{job.repository}.git or #{job.repository}/.git at #{repo_root}"
-          sleep 1
-          next
+          src_repo = File.join(repo_root, job.repository, '.git')
+          if not File.exists? src_repo
+            fail_job job, "No #{job.repository}.git or #{job.repository}/.git at #{repo_root}"
+            next
+          end
         end
-      end
-
-      git = "git --git-dir=#{arvados_internal.shellescape}"
 
-      # check if the commit needs to be fetched or not
-      commit_rev = `#{git} rev-list -n1 #{job.script_version.shellescape} 2>/dev/null`.chomp
-      unless $? == 0 and commit_rev == job.script_version
-        # commit does not exist in internal repository, so import the source repository using git fetch-pack
-        cmd = "#{git} fetch-pack --no-progress --all #{src_repo.shellescape}"
-        $stderr.puts cmd
-        $stderr.puts `#{cmd}`
-        unless $? == 0
-          $stderr.puts "dispatch: git fetch-pack failed"
-          sleep 1
-          next
+        # check if the commit needs to be fetched or not
+        commit_rev = `#{git} rev-list -n1 #{job.script_version.shellescape} 2>/dev/null`.chomp
+        unless $? == 0 and commit_rev == job.script_version
+          # commit does not exist in internal repository, so import the source repository using git fetch-pack
+          cmd = "#{git} fetch-pack --no-progress --all #{src_repo.shellescape}"
+          $stderr.puts cmd
+          $stderr.puts `#{cmd}`
+          unless $? == 0
+            fail_job job, "git fetch-pack failed"
+            next
+          end
         end
+        @fetched_commits[job.script_version] = true
       end
 
-      # check if the commit needs to be tagged with this job uuid
-      tag_rev = `#{git} rev-list -n1 #{job.uuid.shellescape} 2>/dev/null`.chomp
-      if $? != 0
-        # no job tag found, so create one
-        cmd = "#{git} tag #{job.uuid.shellescape} #{job.script_version.shellescape}"
-        $stderr.puts cmd
-        $stderr.puts `#{cmd}`
-        unless $? == 0
-          $stderr.puts "dispatch: git tag failed"
-          sleep 1
-          next
-        end
-      else
-        # job tag found, check that it has the expected revision
-        unless tag_rev == job.script_version
-          # Uh oh, the tag doesn't point to the revision we were expecting.
-          # Someone has been monkeying with the job record and/or git.
-          $stderr.puts "dispatch: Already a tag #{job.script_version} pointing to commit #{tag_rev} but expected commit #{job.script_version}"
-          job.state = "Failed"
-          if not job.save
-            $stderr.puts "dispatch: job.save failed"
+      # @job_tags[J]==V if we know commit V has been tagged J in the
+      # arvados_internal repository. (J is a job UUID, V is a commit
+      # sha1.)
+      @job_tags ||= {}
+      if not @job_tags[job.uuid]
+        # check if the commit needs to be tagged with this job uuid
+        tag_rev = `#{git} rev-list -n1 #{job.uuid.shellescape} 2>/dev/null`.chomp
+        if $? != 0
+          # no job tag found, so create one
+          cmd = "#{git} tag #{job.uuid.shellescape} #{job.script_version.shellescape}"
+          $stderr.puts cmd
+          $stderr.puts `#{cmd}`
+          unless $? == 0
+            fail_job job, "git tag failed"
+            next
+          end
+        else
+          # job tag found, check that it has the expected revision
+          unless tag_rev == job.script_version
+            # Uh oh, the tag doesn't point to the revision we were expecting.
+            # Someone has been monkeying with the job record and/or git.
+            fail_job job, "Existing tag #{job.uuid} points to commit #{tag_rev} but expected commit #{job.script_version}"
             next
           end
-          next
         end
+        @job_tags[job.uuid] = job.script_version
+      elsif @job_tags[job.uuid] != job.script_version
+        fail_job job, "Existing tag #{job.uuid} points to commit #{@job_tags[job.uuid]} but this job uses commit #{job.script_version}"
       end
 
       cmd_args << crunch_job_bin
       cmd_args << '--job-api-token'
-      cmd_args << job_auth.api_token
+      cmd_args << @authorizations[job.uuid].api_token
       cmd_args << '--job'
       cmd_args << job.uuid
       cmd_args << '--git-dir'
@@ -337,67 +373,161 @@ class Dispatcher
         buf: {stderr: '', stdout: ''},
         started: false,
         sent_int: 0,
-        job_auth: job_auth,
+        job_auth: @authorizations[job.uuid],
         stderr_buf_to_flush: '',
-        stderr_flushed_at: 0,
+        stderr_flushed_at: Time.new(0),
         bytes_logged: 0,
         events_logged: 0,
-        log_truncated: false
+        log_throttle_is_open: true,
+        log_throttle_reset_time: Time.now + Rails.configuration.crunch_log_throttle_period,
+        log_throttle_bytes_so_far: 0,
+        log_throttle_lines_so_far: 0,
+        log_throttle_bytes_skipped: 0,
       }
       i.close
       update_node_status
     end
   end
 
+  # Test for hard cap on total output and for log throttling.  Returns whether
+  # the log line should go to output or not.  Modifies "line" in place to
+  # replace it with an error if a logging limit is tripped.
+  def rate_limit running_job, line
+    message = false
+    linesize = line.size
+    if running_job[:log_throttle_is_open]
+      running_job[:log_throttle_lines_so_far] += 1
+      running_job[:log_throttle_bytes_so_far] += linesize
+      running_job[:bytes_logged] += linesize
+
+      if (running_job[:bytes_logged] >
+          Rails.configuration.crunch_limit_log_bytes_per_job)
+        message = "Exceeded log limit #{Rails.configuration.crunch_limit_log_bytes_per_job} bytes (crunch_limit_log_bytes_per_job). Log will be truncated."
+        running_job[:log_throttle_reset_time] = Time.now + 100.years
+        running_job[:log_throttle_is_open] = false
+
+      elsif (running_job[:log_throttle_bytes_so_far] >
+             Rails.configuration.crunch_log_throttle_bytes)
+        remaining_time = running_job[:log_throttle_reset_time] - Time.now
+        message = "Exceeded rate #{Rails.configuration.crunch_log_throttle_bytes} bytes per #{Rails.configuration.crunch_log_throttle_period} seconds (crunch_log_throttle_bytes). Logging will be silenced for the next #{remaining_time.round} seconds.\n"
+        running_job[:log_throttle_is_open] = false
+
+      elsif (running_job[:log_throttle_lines_so_far] >
+             Rails.configuration.crunch_log_throttle_lines)
+        remaining_time = running_job[:log_throttle_reset_time] - Time.now
+        message = "Exceeded rate #{Rails.configuration.crunch_log_throttle_lines} lines per #{Rails.configuration.crunch_log_throttle_period} seconds (crunch_log_throttle_lines), logging will be silenced for the next #{remaining_time.round} seconds.\n"
+        running_job[:log_throttle_is_open] = false
+      end
+    end
+
+    if not running_job[:log_throttle_is_open]
+      # Don't log anything if any limit has been exceeded. Just count lossage.
+      running_job[:log_throttle_bytes_skipped] += linesize
+    end
+
+    if message
+      # Yes, write to logs, but use our "rate exceeded" message
+      # instead of the log message that exceeded the limit.
+      line.replace message
+      true
+    else
+      running_job[:log_throttle_is_open]
+    end
+  end
+
   def read_pipes
     @running.each do |job_uuid, j|
       job = j[:job]
 
+      now = Time.now
+      if now > j[:log_throttle_reset_time]
+        # It has been more than throttle_period seconds since the last
+        # checkpoint so reset the throttle
+        if j[:log_throttle_bytes_skipped] > 0
+          message = "#{job_uuid} ! Skipped #{j[:log_throttle_bytes_skipped]} bytes of log"
+          $stderr.puts message
+          j[:stderr_buf_to_flush] << "#{Time.now.ctime.to_s} #{message}\n"
+        end
+
+        j[:log_throttle_reset_time] = now + Rails.configuration.crunch_log_throttle_period
+        j[:log_throttle_bytes_so_far] = 0
+        j[:log_throttle_lines_so_far] = 0
+        j[:log_throttle_bytes_skipped] = 0
+        j[:log_throttle_is_open] = true
+      end
+
       j[:buf].each do |stream, streambuf|
         # Read some data from the child stream
-        buf = false
+        buf = ''
         begin
-          buf = j[stream].read_nonblock(2**16)
+          # It's important to use a big enough buffer here. When we're
+          # being flooded with logs, we must read and discard many
+          # bytes at once. Otherwise, we can easily peg a CPU with
+          # time-checking and other loop overhead. (Quick tests show a
+          # 1MiB buffer working 2.5x as fast as a 64 KiB buffer.)
+          #
+          # So don't reduce this buffer size!
+          buf = j[stream].read_nonblock(2**20)
         rescue Errno::EAGAIN, EOFError
         end
 
-        if buf
-          # Add to a the buffer
-          streambuf << buf
-
-          # Check for at least one complete line
-          if streambuf.index "\n"
-            lines = streambuf.lines("\n").to_a
-
-            # check if the last line is partial or not
-            j[:buf][stream] = if streambuf[-1] == "\n"
-                                # nope
-                                ''
-                              else
-                                # Put the partial line back into the buffer
-                                lines.pop
-                              end
-
-            # Now spool the lines to the log output buffer
-            lines.each do |line|
-              $stderr.print "#{job_uuid} ! " unless line.index(job_uuid)
-              $stderr.puts line
-              pub_msg = "#{Time.now.ctime.to_s} #{line.strip} \n"
-              if not j[:log_truncated]
-                j[:stderr_buf_to_flush] << pub_msg
-              end
-            end
+        # Short circuit the counting code if we're just going to throw
+        # away the data anyway.
+        if not j[:log_throttle_is_open]
+          j[:log_throttle_bytes_skipped] += streambuf.size + buf.size
+          streambuf.replace ''
+          next
+        elsif buf == ''
+          next
+        end
 
-            # Now actually send the log output to the logs table
-            if not j[:log_truncated]
-              if (Rails.configuration.crunch_log_bytes_per_event < j[:stderr_buf_to_flush].size or
-                  (j[:stderr_flushed_at] + Rails.configuration.crunch_log_seconds_between_events < Time.now.to_i))
-                write_log j
-              end
+        # Append to incomplete line from previous read, if any
+        streambuf << buf
+
+        bufend = ''
+        streambuf.each_line do |line|
+          if not line.end_with? $/
+            if line.size > Rails.configuration.crunch_log_throttle_bytes
+              # Without a limit here, we'll use 2x an arbitrary amount
+              # of memory, and waste a lot of time copying strings
+              # around, all without providing any feedback to anyone
+              # about what's going on _or_ hitting any of our throttle
+              # limits.
+              #
+              # Here we leave "line" alone, knowing it will never be
+              # sent anywhere: rate_limit() will reach
+              # crunch_log_throttle_bytes immediately. However, we'll
+              # leave [...] in bufend: if the trailing end of the long
+              # line does end up getting sent anywhere, it will have
+              # some indication that it is incomplete.
+              bufend = "[...]"
+            else
+              # If line length is sane, we'll wait for the rest of the
+              # line to appear in the next read_pipes() call.
+              bufend = line
+              break
             end
           end
+          # rate_limit returns true or false as to whether to actually log
+          # the line or not.  It also modifies "line" in place to replace
+          # it with an error if a logging limit is tripped.
+          if rate_limit j, line
+            $stderr.print "#{job_uuid} ! " unless line.index(job_uuid)
+            $stderr.puts line
+            pub_msg = "#{Time.now.ctime.to_s} #{line.strip}\n"
+            j[:stderr_buf_to_flush] << pub_msg
+          end
         end
+
+        # Leave the trailing incomplete line (if any) in streambuf for
+        # next time.
+        streambuf.replace bufend
       end
+      # Flush buffered logs to the logs table, if appropriate. We have
+      # to do this even if we didn't collect any new logs this time:
+      # otherwise, buffered data older than seconds_between_events
+      # won't get flushed until new data arrives.
+      write_log j
     end
   end
 
@@ -440,9 +570,12 @@ class Dispatcher
     $stderr.puts "dispatch: child #{pid_done} exit"
     $stderr.puts "dispatch: job #{job_done.uuid} end"
 
-    # Ensure every last drop of stdout and stderr is consumed
+    # Ensure every last drop of stdout and stderr is consumed.
     read_pipes
-    write_log j_done # write any remaining logs
+    # Reset flush timestamp to make sure log gets written.
+    j_done[:stderr_flushed_at] = Time.new(0)
+    # Write any remaining logs.
+    write_log j_done
 
     j_done[:buf].each do |stream, streambuf|
       if streambuf != ''
@@ -451,15 +584,17 @@ class Dispatcher
     end
 
     # Wait the thread (returns a Process::Status)
-    exit_status = j_done[:wait_thr].value
+    exit_status = j_done[:wait_thr].value.exitstatus
 
     jobrecord = Job.find_by_uuid(job_done.uuid)
-    if exit_status.to_i != 75 and jobrecord.state == "Running"
+    if exit_status != 75 and jobrecord.state == "Running"
       # crunch-job did not return exit code 75 (see below) and left the job in
       # the "Running" state, which means there was an unhandled error.  Fail
       # the job.
       jobrecord.state = "Failed"
-      jobrecord.save!
+      if not jobrecord.save
+        $stderr.puts "dispatch: jobrecord.save failed"
+      end
     else
       # Don't fail the job if crunch-job didn't even get as far as
       # starting it. If the job failed to run due to an infrastructure
@@ -521,7 +656,7 @@ class Dispatcher
         end
       else
         refresh_todo unless did_recently(:refresh_todo, 1.0)
-        update_node_status
+        update_node_status unless did_recently(:update_node_status, 1.0)
         unless @todo.empty? or did_recently(:start_jobs, 1.0) or $signal[:term]
           start_jobs
         end
@@ -537,15 +672,6 @@ class Dispatcher
 
   protected
 
-  def too_many_bytes_logged_for_job(j)
-    return (j[:bytes_logged] + j[:stderr_buf_to_flush].size >
-            Rails.configuration.crunch_limit_log_event_bytes_per_job)
-  end
-
-  def too_many_events_logged_for_job(j)
-    return (j[:events_logged] >= Rails.configuration.crunch_limit_log_events_per_job)
-  end
-
   def did_recently(thing, min_interval)
     @did_recently ||= {}
     if !@did_recently[thing] or @did_recently[thing] < Time.now - min_interval
@@ -558,34 +684,28 @@ class Dispatcher
 
   # send message to log table. we want these records to be transient
   def write_log running_job
-    return if running_job[:log_truncated]
     return if running_job[:stderr_buf_to_flush] == ''
-    begin
-      # Truncate logs if they exceed crunch_limit_log_event_bytes_per_job
-      # or crunch_limit_log_events_per_job.
-      if (too_many_bytes_logged_for_job(running_job))
-        running_job[:log_truncated] = true
-        running_job[:stderr_buf_to_flush] =
-          "Server configured limit reached (crunch_limit_log_event_bytes_per_job: #{Rails.configuration.crunch_limit_log_event_bytes_per_job}). Subsequent logs truncated"
-      elsif (too_many_events_logged_for_job(running_job))
-        running_job[:log_truncated] = true
-        running_job[:stderr_buf_to_flush] =
-          "Server configured limit reached (crunch_limit_log_events_per_job: #{Rails.configuration.crunch_limit_log_events_per_job}). Subsequent logs truncated"
+
+    # Send out to log event if buffer size exceeds the bytes per event or if
+    # it has been at least crunch_log_seconds_between_events seconds since
+    # the last flush.
+    if running_job[:stderr_buf_to_flush].size > Rails.configuration.crunch_log_bytes_per_event or
+        (Time.now - running_job[:stderr_flushed_at]) >= Rails.configuration.crunch_log_seconds_between_events
+      begin
+        log = Log.new(object_uuid: running_job[:job].uuid,
+                      event_type: 'stderr',
+                      owner_uuid: running_job[:job].owner_uuid,
+                      properties: {"text" => running_job[:stderr_buf_to_flush]})
+        log.save!
+        running_job[:events_logged] += 1
+      rescue => exception
+        $stderr.puts "Failed to write logs"
+        $stderr.puts exception.backtrace
       end
-      log = Log.new(object_uuid: running_job[:job].uuid,
-                    event_type: 'stderr',
-                    owner_uuid: running_job[:job].owner_uuid,
-                    properties: {"text" => running_job[:stderr_buf_to_flush]})
-      log.save!
-      running_job[:bytes_logged] += running_job[:stderr_buf_to_flush].size
-      running_job[:events_logged] += 1
-    rescue
-      running_job[:buf][:stderr] = "Failed to write logs\n" + running_job[:buf][:stderr]
+      running_job[:stderr_buf_to_flush] = ''
+      running_job[:stderr_flushed_at] = Time.now
     end
-    running_job[:stderr_buf_to_flush] = ''
-    running_job[:stderr_flushed_at] = Time.now.to_i
   end
-
 end
 
 # This is how crunch-job child procs know where the "refresh" trigger file is