1 | <?xml version="1.0"?> |
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2 | <?xml-stylesheet type="text/xsl" href="configuration.xsl"?> |
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3 | |
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4 | <!-- Do not modify this file directly. Instead, copy entries that you --> |
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5 | <!-- wish to modify from this file into mapred-site.xml and change them --> |
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6 | <!-- there. If mapred-site.xml does not already exist, create it. --> |
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7 | |
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8 | <configuration> |
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9 | |
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10 | <property> |
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11 | <name>hadoop.job.history.location</name> |
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12 | <value></value> |
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13 | <description> If job tracker is static the history files are stored |
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14 | in this single well known place. If No value is set here, by default, |
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15 | it is in the local file system at ${hadoop.log.dir}/history. |
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16 | </description> |
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17 | </property> |
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18 | |
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19 | <property> |
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20 | <name>hadoop.job.history.user.location</name> |
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21 | <value></value> |
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22 | <description> User can specify a location to store the history files of |
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23 | a particular job. If nothing is specified, the logs are stored in |
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24 | output directory. The files are stored in "_logs/history/" in the directory. |
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25 | User can stop logging by giving the value "none". |
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26 | </description> |
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27 | </property> |
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28 | |
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29 | <!-- i/o properties --> |
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30 | |
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31 | <property> |
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32 | <name>io.sort.factor</name> |
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33 | <value>10</value> |
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34 | <description>The number of streams to merge at once while sorting |
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35 | files. This determines the number of open file handles.</description> |
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36 | </property> |
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37 | |
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38 | <property> |
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39 | <name>io.sort.mb</name> |
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40 | <value>100</value> |
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41 | <description>The total amount of buffer memory to use while sorting |
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42 | files, in megabytes. By default, gives each merge stream 1MB, which |
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43 | should minimize seeks.</description> |
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44 | </property> |
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45 | |
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46 | <property> |
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47 | <name>io.sort.record.percent</name> |
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48 | <value>0.05</value> |
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49 | <description>The percentage of io.sort.mb dedicated to tracking record |
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50 | boundaries. Let this value be r, io.sort.mb be x. The maximum number |
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51 | of records collected before the collection thread must block is equal |
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52 | to (r * x) / 4</description> |
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53 | </property> |
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54 | |
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55 | <property> |
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56 | <name>io.sort.spill.percent</name> |
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57 | <value>0.80</value> |
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58 | <description>The soft limit in either the buffer or record collection |
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59 | buffers. Once reached, a thread will begin to spill the contents to disk |
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60 | in the background. Note that this does not imply any chunking of data to |
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61 | the spill. A value less than 0.5 is not recommended.</description> |
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62 | </property> |
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63 | |
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64 | <property> |
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65 | <name>io.map.index.skip</name> |
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66 | <value>0</value> |
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67 | <description>Number of index entries to skip between each entry. |
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68 | Zero by default. Setting this to values larger than zero can |
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69 | facilitate opening large map files using less memory.</description> |
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70 | </property> |
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71 | |
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72 | <property> |
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73 | <name>mapred.job.tracker</name> |
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74 | <value>local</value> |
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75 | <description>The host and port that the MapReduce job tracker runs |
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76 | at. If "local", then jobs are run in-process as a single map |
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77 | and reduce task. |
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78 | </description> |
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79 | </property> |
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80 | |
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81 | <property> |
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82 | <name>mapred.job.tracker.http.address</name> |
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83 | <value>0.0.0.0:50030</value> |
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84 | <description> |
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85 | The job tracker http server address and port the server will listen on. |
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86 | If the port is 0 then the server will start on a free port. |
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87 | </description> |
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88 | </property> |
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89 | |
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90 | <property> |
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91 | <name>mapred.job.tracker.handler.count</name> |
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92 | <value>10</value> |
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93 | <description> |
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94 | The number of server threads for the JobTracker. This should be roughly |
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95 | 4% of the number of tasktracker nodes. |
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96 | </description> |
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97 | </property> |
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98 | |
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99 | <property> |
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100 | <name>mapred.task.tracker.report.address</name> |
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101 | <value>127.0.0.1:0</value> |
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102 | <description>The interface and port that task tracker server listens on. |
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103 | Since it is only connected to by the tasks, it uses the local interface. |
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104 | EXPERT ONLY. Should only be changed if your host does not have the loopback |
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105 | interface.</description> |
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106 | </property> |
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107 | |
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108 | <property> |
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109 | <name>mapred.local.dir</name> |
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110 | <value>${hadoop.tmp.dir}/mapred/local</value> |
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111 | <description>The local directory where MapReduce stores intermediate |
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112 | data files. May be a comma-separated list of |
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113 | directories on different devices in order to spread disk i/o. |
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114 | Directories that do not exist are ignored. |
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115 | </description> |
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116 | </property> |
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117 | |
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118 | <property> |
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119 | <name>mapred.system.dir</name> |
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120 | <value>${hadoop.tmp.dir}/mapred/system</value> |
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121 | <description>The shared directory where MapReduce stores control files. |
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122 | </description> |
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123 | </property> |
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124 | |
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125 | <property> |
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126 | <name>mapred.temp.dir</name> |
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127 | <value>${hadoop.tmp.dir}/mapred/temp</value> |
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128 | <description>A shared directory for temporary files. |
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129 | </description> |
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130 | </property> |
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131 | |
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132 | <property> |
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133 | <name>mapred.local.dir.minspacestart</name> |
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134 | <value>0</value> |
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135 | <description>If the space in mapred.local.dir drops under this, |
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136 | do not ask for more tasks. |
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137 | Value in bytes. |
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138 | </description> |
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139 | </property> |
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140 | |
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141 | <property> |
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142 | <name>mapred.local.dir.minspacekill</name> |
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143 | <value>0</value> |
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144 | <description>If the space in mapred.local.dir drops under this, |
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145 | do not ask more tasks until all the current ones have finished and |
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146 | cleaned up. Also, to save the rest of the tasks we have running, |
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147 | kill one of them, to clean up some space. Start with the reduce tasks, |
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148 | then go with the ones that have finished the least. |
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149 | Value in bytes. |
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150 | </description> |
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151 | </property> |
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152 | |
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153 | <property> |
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154 | <name>mapred.tasktracker.expiry.interval</name> |
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155 | <value>600000</value> |
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156 | <description>Expert: The time-interval, in miliseconds, after which |
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157 | a tasktracker is declared 'lost' if it doesn't send heartbeats. |
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158 | </description> |
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159 | </property> |
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160 | |
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161 | <property> |
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162 | <name>mapred.tasktracker.instrumentation</name> |
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163 | <value>org.apache.hadoop.mapred.TaskTrackerMetricsInst</value> |
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164 | <description>Expert: The instrumentation class to associate with each TaskTracker. |
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165 | </description> |
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166 | </property> |
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167 | |
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168 | <property> |
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169 | <name>mapred.tasktracker.memory_calculator_plugin</name> |
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170 | <value></value> |
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171 | <description> |
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172 | Name of the class whose instance will be used to query memory information |
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173 | on the tasktracker. |
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174 | |
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175 | The class must be an instance of |
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176 | org.apache.hadoop.util.MemoryCalculatorPlugin. If the value is null, the |
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177 | tasktracker attempts to use a class appropriate to the platform. |
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178 | Currently, the only platform supported is Linux. |
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179 | </description> |
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180 | </property> |
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181 | |
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182 | <property> |
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183 | <name>mapred.tasktracker.taskmemorymanager.monitoring-interval</name> |
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184 | <value>5000</value> |
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185 | <description>The interval, in milliseconds, for which the tasktracker waits |
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186 | between two cycles of monitoring its tasks' memory usage. Used only if |
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187 | tasks' memory management is enabled via mapred.tasktracker.tasks.maxmemory. |
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188 | </description> |
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189 | </property> |
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190 | |
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191 | <property> |
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192 | <name>mapred.tasktracker.procfsbasedprocesstree.sleeptime-before-sigkill</name> |
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193 | <value>5000</value> |
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194 | <description>The time, in milliseconds, the tasktracker waits for sending a |
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195 | SIGKILL to a process that has overrun memory limits, after it has been sent |
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196 | a SIGTERM. Used only if tasks' memory management is enabled via |
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197 | mapred.tasktracker.tasks.maxmemory.</description> |
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198 | </property> |
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199 | |
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200 | <property> |
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201 | <name>mapred.map.tasks</name> |
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202 | <value>2</value> |
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203 | <description>The default number of map tasks per job. |
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204 | Ignored when mapred.job.tracker is "local". |
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205 | </description> |
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206 | </property> |
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207 | |
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208 | <property> |
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209 | <name>mapred.reduce.tasks</name> |
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210 | <value>1</value> |
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211 | <description>The default number of reduce tasks per job. Typically set to 99% |
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212 | of the cluster's reduce capacity, so that if a node fails the reduces can |
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213 | still be executed in a single wave. |
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214 | Ignored when mapred.job.tracker is "local". |
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215 | </description> |
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216 | </property> |
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217 | |
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218 | <property> |
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219 | <name>mapred.jobtracker.restart.recover</name> |
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220 | <value>false</value> |
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221 | <description>"true" to enable (job) recovery upon restart, |
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222 | "false" to start afresh |
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223 | </description> |
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224 | </property> |
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225 | |
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226 | <property> |
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227 | <name>mapred.jobtracker.job.history.block.size</name> |
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228 | <value>3145728</value> |
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229 | <description>The block size of the job history file. Since the job recovery |
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230 | uses job history, its important to dump job history to disk as |
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231 | soon as possible. Note that this is an expert level parameter. |
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232 | The default value is set to 3 MB. |
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233 | </description> |
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234 | </property> |
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235 | |
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236 | <property> |
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237 | <name>mapred.jobtracker.taskScheduler</name> |
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238 | <value>org.apache.hadoop.mapred.JobQueueTaskScheduler</value> |
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239 | <description>The class responsible for scheduling the tasks.</description> |
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240 | </property> |
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241 | |
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242 | <property> |
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243 | <name>mapred.jobtracker.taskScheduler.maxRunningTasksPerJob</name> |
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244 | <value></value> |
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245 | <description>The maximum number of running tasks for a job before |
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246 | it gets preempted. No limits if undefined. |
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247 | </description> |
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248 | </property> |
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249 | |
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250 | <property> |
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251 | <name>mapred.map.max.attempts</name> |
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252 | <value>4</value> |
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253 | <description>Expert: The maximum number of attempts per map task. |
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254 | In other words, framework will try to execute a map task these many number |
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255 | of times before giving up on it. |
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256 | </description> |
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257 | </property> |
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258 | |
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259 | <property> |
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260 | <name>mapred.reduce.max.attempts</name> |
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261 | <value>4</value> |
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262 | <description>Expert: The maximum number of attempts per reduce task. |
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263 | In other words, framework will try to execute a reduce task these many number |
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264 | of times before giving up on it. |
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265 | </description> |
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266 | </property> |
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267 | |
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268 | <property> |
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269 | <name>mapred.reduce.parallel.copies</name> |
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270 | <value>5</value> |
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271 | <description>The default number of parallel transfers run by reduce |
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272 | during the copy(shuffle) phase. |
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273 | </description> |
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274 | </property> |
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275 | |
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276 | <property> |
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277 | <name>mapred.reduce.copy.backoff</name> |
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278 | <value>300</value> |
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279 | <description>The maximum amount of time (in seconds) a reducer spends on |
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280 | fetching one map output before declaring it as failed. |
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281 | </description> |
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282 | </property> |
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283 | |
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284 | <property> |
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285 | <name>mapred.task.timeout</name> |
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286 | <value>600000</value> |
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287 | <description>The number of milliseconds before a task will be |
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288 | terminated if it neither reads an input, writes an output, nor |
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289 | updates its status string. |
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290 | </description> |
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291 | </property> |
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292 | |
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293 | <property> |
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294 | <name>mapred.tasktracker.map.tasks.maximum</name> |
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295 | <value>2</value> |
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296 | <description>The maximum number of map tasks that will be run |
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297 | simultaneously by a task tracker. |
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298 | </description> |
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299 | </property> |
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300 | |
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301 | <property> |
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302 | <name>mapred.tasktracker.reduce.tasks.maximum</name> |
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303 | <value>2</value> |
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304 | <description>The maximum number of reduce tasks that will be run |
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305 | simultaneously by a task tracker. |
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306 | </description> |
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307 | </property> |
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308 | |
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309 | <property> |
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310 | <name>mapred.jobtracker.completeuserjobs.maximum</name> |
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311 | <value>100</value> |
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312 | <description>The maximum number of complete jobs per user to keep around |
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313 | before delegating them to the job history.</description> |
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314 | </property> |
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315 | |
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316 | <property> |
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317 | <name>mapred.jobtracker.instrumentation</name> |
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318 | <value>org.apache.hadoop.mapred.JobTrackerMetricsInst</value> |
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319 | <description>Expert: The instrumentation class to associate with each JobTracker. |
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320 | </description> |
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321 | </property> |
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322 | |
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323 | <property> |
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324 | <name>mapred.child.java.opts</name> |
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325 | <value>-Xmx200m</value> |
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326 | <description>Java opts for the task tracker child processes. |
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327 | The following symbol, if present, will be interpolated: @taskid@ is replaced |
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328 | by current TaskID. Any other occurrences of '@' will go unchanged. |
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329 | For example, to enable verbose gc logging to a file named for the taskid in |
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330 | /tmp and to set the heap maximum to be a gigabyte, pass a 'value' of: |
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331 | -Xmx1024m -verbose:gc -Xloggc:/tmp/@taskid@.gc |
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332 | |
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333 | The configuration variable mapred.child.ulimit can be used to control the |
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334 | maximum virtual memory of the child processes. |
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335 | </description> |
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336 | </property> |
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337 | |
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338 | <property> |
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339 | <name>mapred.child.ulimit</name> |
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340 | <value></value> |
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341 | <description>The maximum virtual memory, in KB, of a process launched by the |
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342 | Map-Reduce framework. This can be used to control both the Mapper/Reducer |
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343 | tasks and applications using Hadoop Pipes, Hadoop Streaming etc. |
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344 | By default it is left unspecified to let cluster admins control it via |
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345 | limits.conf and other such relevant mechanisms. |
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346 | |
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347 | Note: mapred.child.ulimit must be greater than or equal to the -Xmx passed to |
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348 | JavaVM, else the VM might not start. |
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349 | </description> |
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350 | </property> |
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351 | |
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352 | <property> |
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353 | <name>mapred.child.tmp</name> |
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354 | <value>./tmp</value> |
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355 | <description> To set the value of tmp directory for map and reduce tasks. |
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356 | If the value is an absolute path, it is directly assigned. Otherwise, it is |
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357 | prepended with task's working directory. The java tasks are executed with |
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358 | option -Djava.io.tmpdir='the absolute path of the tmp dir'. Pipes and |
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359 | streaming are set with environment variable, |
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360 | TMPDIR='the absolute path of the tmp dir' |
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361 | </description> |
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362 | </property> |
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363 | |
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364 | <property> |
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365 | <name>mapred.inmem.merge.threshold</name> |
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366 | <value>1000</value> |
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367 | <description>The threshold, in terms of the number of files |
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368 | for the in-memory merge process. When we accumulate threshold number of files |
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369 | we initiate the in-memory merge and spill to disk. A value of 0 or less than |
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370 | 0 indicates we want to DON'T have any threshold and instead depend only on |
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371 | the ramfs's memory consumption to trigger the merge. |
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372 | </description> |
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373 | </property> |
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374 | |
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375 | <property> |
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376 | <name>mapred.job.shuffle.merge.percent</name> |
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377 | <value>0.66</value> |
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378 | <description>The usage threshold at which an in-memory merge will be |
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379 | initiated, expressed as a percentage of the total memory allocated to |
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380 | storing in-memory map outputs, as defined by |
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381 | mapred.job.shuffle.input.buffer.percent. |
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382 | </description> |
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383 | </property> |
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384 | |
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385 | <property> |
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386 | <name>mapred.job.shuffle.input.buffer.percent</name> |
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387 | <value>0.70</value> |
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388 | <description>The percentage of memory to be allocated from the maximum heap |
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389 | size to storing map outputs during the shuffle. |
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390 | </description> |
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391 | </property> |
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392 | |
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393 | <property> |
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394 | <name>mapred.job.reduce.input.buffer.percent</name> |
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395 | <value>0.0</value> |
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396 | <description>The percentage of memory- relative to the maximum heap size- to |
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397 | retain map outputs during the reduce. When the shuffle is concluded, any |
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398 | remaining map outputs in memory must consume less than this threshold before |
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399 | the reduce can begin. |
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400 | </description> |
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401 | </property> |
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402 | |
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403 | <property> |
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404 | <name>mapred.map.tasks.speculative.execution</name> |
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405 | <value>true</value> |
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406 | <description>If true, then multiple instances of some map tasks |
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407 | may be executed in parallel.</description> |
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408 | </property> |
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409 | |
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410 | <property> |
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411 | <name>mapred.reduce.tasks.speculative.execution</name> |
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412 | <value>true</value> |
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413 | <description>If true, then multiple instances of some reduce tasks |
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414 | may be executed in parallel.</description> |
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415 | </property> |
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416 | |
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417 | <property> |
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418 | <name>mapred.job.reuse.jvm.num.tasks</name> |
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419 | <value>1</value> |
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420 | <description>How many tasks to run per jvm. If set to -1, there is |
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421 | no limit. |
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422 | </description> |
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423 | </property> |
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424 | |
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425 | <property> |
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426 | <name>mapred.min.split.size</name> |
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427 | <value>0</value> |
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428 | <description>The minimum size chunk that map input should be split |
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429 | into. Note that some file formats may have minimum split sizes that |
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430 | take priority over this setting.</description> |
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431 | </property> |
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432 | |
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433 | <property> |
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434 | <name>mapred.jobtracker.maxtasks.per.job</name> |
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435 | <value>-1</value> |
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436 | <description>The maximum number of tasks for a single job. |
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437 | A value of -1 indicates that there is no maximum. </description> |
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438 | </property> |
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439 | |
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440 | <property> |
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441 | <name>mapred.submit.replication</name> |
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442 | <value>10</value> |
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443 | <description>The replication level for submitted job files. This |
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444 | should be around the square root of the number of nodes. |
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445 | </description> |
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446 | </property> |
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447 | |
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448 | |
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449 | <property> |
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450 | <name>mapred.tasktracker.dns.interface</name> |
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451 | <value>default</value> |
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452 | <description>The name of the Network Interface from which a task |
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453 | tracker should report its IP address. |
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454 | </description> |
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455 | </property> |
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456 | |
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457 | <property> |
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458 | <name>mapred.tasktracker.dns.nameserver</name> |
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459 | <value>default</value> |
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460 | <description>The host name or IP address of the name server (DNS) |
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461 | which a TaskTracker should use to determine the host name used by |
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462 | the JobTracker for communication and display purposes. |
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463 | </description> |
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464 | </property> |
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465 | |
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466 | <property> |
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467 | <name>tasktracker.http.threads</name> |
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468 | <value>40</value> |
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469 | <description>The number of worker threads that for the http server. This is |
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470 | used for map output fetching |
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471 | </description> |
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472 | </property> |
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473 | |
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474 | <property> |
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475 | <name>mapred.task.tracker.http.address</name> |
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476 | <value>0.0.0.0:50060</value> |
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477 | <description> |
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478 | The task tracker http server address and port. |
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479 | If the port is 0 then the server will start on a free port. |
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480 | </description> |
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481 | </property> |
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482 | |
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483 | <property> |
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484 | <name>keep.failed.task.files</name> |
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485 | <value>false</value> |
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486 | <description>Should the files for failed tasks be kept. This should only be |
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487 | used on jobs that are failing, because the storage is never |
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488 | reclaimed. It also prevents the map outputs from being erased |
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489 | from the reduce directory as they are consumed.</description> |
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490 | </property> |
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491 | |
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492 | |
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493 | <!-- |
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494 | <property> |
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495 | <name>keep.task.files.pattern</name> |
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496 | <value>.*_m_123456_0</value> |
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497 | <description>Keep all files from tasks whose task names match the given |
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498 | regular expression. Defaults to none.</description> |
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499 | </property> |
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500 | --> |
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501 | |
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502 | <property> |
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503 | <name>mapred.output.compress</name> |
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504 | <value>false</value> |
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505 | <description>Should the job outputs be compressed? |
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506 | </description> |
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507 | </property> |
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508 | |
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509 | <property> |
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510 | <name>mapred.output.compression.type</name> |
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511 | <value>RECORD</value> |
---|
512 | <description>If the job outputs are to compressed as SequenceFiles, how should |
---|
513 | they be compressed? Should be one of NONE, RECORD or BLOCK. |
---|
514 | </description> |
---|
515 | </property> |
---|
516 | |
---|
517 | <property> |
---|
518 | <name>mapred.output.compression.codec</name> |
---|
519 | <value>org.apache.hadoop.io.compress.DefaultCodec</value> |
---|
520 | <description>If the job outputs are compressed, how should they be compressed? |
---|
521 | </description> |
---|
522 | </property> |
---|
523 | |
---|
524 | <property> |
---|
525 | <name>mapred.compress.map.output</name> |
---|
526 | <value>false</value> |
---|
527 | <description>Should the outputs of the maps be compressed before being |
---|
528 | sent across the network. Uses SequenceFile compression. |
---|
529 | </description> |
---|
530 | </property> |
---|
531 | |
---|
532 | <property> |
---|
533 | <name>mapred.map.output.compression.codec</name> |
---|
534 | <value>org.apache.hadoop.io.compress.DefaultCodec</value> |
---|
535 | <description>If the map outputs are compressed, how should they be |
---|
536 | compressed? |
---|
537 | </description> |
---|
538 | </property> |
---|
539 | |
---|
540 | <property> |
---|
541 | <name>map.sort.class</name> |
---|
542 | <value>org.apache.hadoop.util.QuickSort</value> |
---|
543 | <description>The default sort class for sorting keys. |
---|
544 | </description> |
---|
545 | </property> |
---|
546 | |
---|
547 | <property> |
---|
548 | <name>mapred.userlog.limit.kb</name> |
---|
549 | <value>0</value> |
---|
550 | <description>The maximum size of user-logs of each task in KB. 0 disables the cap. |
---|
551 | </description> |
---|
552 | </property> |
---|
553 | |
---|
554 | <property> |
---|
555 | <name>mapred.userlog.retain.hours</name> |
---|
556 | <value>24</value> |
---|
557 | <description>The maximum time, in hours, for which the user-logs are to be |
---|
558 | retained. |
---|
559 | </description> |
---|
560 | </property> |
---|
561 | |
---|
562 | <property> |
---|
563 | <name>mapred.hosts</name> |
---|
564 | <value></value> |
---|
565 | <description>Names a file that contains the list of nodes that may |
---|
566 | connect to the jobtracker. If the value is empty, all hosts are |
---|
567 | permitted.</description> |
---|
568 | </property> |
---|
569 | |
---|
570 | <property> |
---|
571 | <name>mapred.hosts.exclude</name> |
---|
572 | <value></value> |
---|
573 | <description>Names a file that contains the list of hosts that |
---|
574 | should be excluded by the jobtracker. If the value is empty, no |
---|
575 | hosts are excluded.</description> |
---|
576 | </property> |
---|
577 | |
---|
578 | <property> |
---|
579 | <name>mapred.max.tracker.blacklists</name> |
---|
580 | <value>4</value> |
---|
581 | <description>The number of blacklists for a taskTracker by various jobs |
---|
582 | after which the task tracker could be blacklisted across |
---|
583 | all jobs. The tracker will be given a tasks later |
---|
584 | (after a day). The tracker will become a healthy |
---|
585 | tracker after a restart. |
---|
586 | </description> |
---|
587 | </property> |
---|
588 | |
---|
589 | <property> |
---|
590 | <name>mapred.max.tracker.failures</name> |
---|
591 | <value>4</value> |
---|
592 | <description>The number of task-failures on a tasktracker of a given job |
---|
593 | after which new tasks of that job aren't assigned to it. |
---|
594 | </description> |
---|
595 | </property> |
---|
596 | |
---|
597 | <property> |
---|
598 | <name>jobclient.output.filter</name> |
---|
599 | <value>FAILED</value> |
---|
600 | <description>The filter for controlling the output of the task's userlogs sent |
---|
601 | to the console of the JobClient. |
---|
602 | The permissible options are: NONE, KILLED, FAILED, SUCCEEDED and |
---|
603 | ALL. |
---|
604 | </description> |
---|
605 | </property> |
---|
606 | |
---|
607 | <property> |
---|
608 | <name>mapred.job.tracker.persist.jobstatus.active</name> |
---|
609 | <value>false</value> |
---|
610 | <description>Indicates if persistency of job status information is |
---|
611 | active or not. |
---|
612 | </description> |
---|
613 | </property> |
---|
614 | |
---|
615 | <property> |
---|
616 | <name>mapred.job.tracker.persist.jobstatus.hours</name> |
---|
617 | <value>0</value> |
---|
618 | <description>The number of hours job status information is persisted in DFS. |
---|
619 | The job status information will be available after it drops of the memory |
---|
620 | queue and between jobtracker restarts. With a zero value the job status |
---|
621 | information is not persisted at all in DFS. |
---|
622 | </description> |
---|
623 | </property> |
---|
624 | |
---|
625 | <property> |
---|
626 | <name>mapred.job.tracker.persist.jobstatus.dir</name> |
---|
627 | <value>/jobtracker/jobsInfo</value> |
---|
628 | <description>The directory where the job status information is persisted |
---|
629 | in a file system to be available after it drops of the memory queue and |
---|
630 | between jobtracker restarts. |
---|
631 | </description> |
---|
632 | </property> |
---|
633 | |
---|
634 | <property> |
---|
635 | <name>mapred.task.profile</name> |
---|
636 | <value>false</value> |
---|
637 | <description>To set whether the system should collect profiler |
---|
638 | information for some of the tasks in this job? The information is stored |
---|
639 | in the user log directory. The value is "true" if task profiling |
---|
640 | is enabled.</description> |
---|
641 | </property> |
---|
642 | |
---|
643 | <property> |
---|
644 | <name>mapred.task.profile.maps</name> |
---|
645 | <value>0-2</value> |
---|
646 | <description> To set the ranges of map tasks to profile. |
---|
647 | mapred.task.profile has to be set to true for the value to be accounted. |
---|
648 | </description> |
---|
649 | </property> |
---|
650 | |
---|
651 | <property> |
---|
652 | <name>mapred.task.profile.reduces</name> |
---|
653 | <value>0-2</value> |
---|
654 | <description> To set the ranges of reduce tasks to profile. |
---|
655 | mapred.task.profile has to be set to true for the value to be accounted. |
---|
656 | </description> |
---|
657 | </property> |
---|
658 | |
---|
659 | <property> |
---|
660 | <name>mapred.line.input.format.linespermap</name> |
---|
661 | <value>1</value> |
---|
662 | <description> Number of lines per split in NLineInputFormat. |
---|
663 | </description> |
---|
664 | </property> |
---|
665 | |
---|
666 | <property> |
---|
667 | <name>mapred.skip.attempts.to.start.skipping</name> |
---|
668 | <value>2</value> |
---|
669 | <description> The number of Task attempts AFTER which skip mode |
---|
670 | will be kicked off. When skip mode is kicked off, the |
---|
671 | tasks reports the range of records which it will process |
---|
672 | next, to the TaskTracker. So that on failures, TT knows which |
---|
673 | ones are possibly the bad records. On further executions, |
---|
674 | those are skipped. |
---|
675 | </description> |
---|
676 | </property> |
---|
677 | |
---|
678 | <property> |
---|
679 | <name>mapred.skip.map.auto.incr.proc.count</name> |
---|
680 | <value>true</value> |
---|
681 | <description> The flag which if set to true, |
---|
682 | SkipBadRecords.COUNTER_MAP_PROCESSED_RECORDS is incremented |
---|
683 | by MapRunner after invoking the map function. This value must be set to |
---|
684 | false for applications which process the records asynchronously |
---|
685 | or buffer the input records. For example streaming. |
---|
686 | In such cases applications should increment this counter on their own. |
---|
687 | </description> |
---|
688 | </property> |
---|
689 | |
---|
690 | <property> |
---|
691 | <name>mapred.skip.reduce.auto.incr.proc.count</name> |
---|
692 | <value>true</value> |
---|
693 | <description> The flag which if set to true, |
---|
694 | SkipBadRecords.COUNTER_REDUCE_PROCESSED_GROUPS is incremented |
---|
695 | by framework after invoking the reduce function. This value must be set to |
---|
696 | false for applications which process the records asynchronously |
---|
697 | or buffer the input records. For example streaming. |
---|
698 | In such cases applications should increment this counter on their own. |
---|
699 | </description> |
---|
700 | </property> |
---|
701 | |
---|
702 | <property> |
---|
703 | <name>mapred.skip.out.dir</name> |
---|
704 | <value></value> |
---|
705 | <description> If no value is specified here, the skipped records are |
---|
706 | written to the output directory at _logs/skip. |
---|
707 | User can stop writing skipped records by giving the value "none". |
---|
708 | </description> |
---|
709 | </property> |
---|
710 | |
---|
711 | <property> |
---|
712 | <name>mapred.skip.map.max.skip.records</name> |
---|
713 | <value>0</value> |
---|
714 | <description> The number of acceptable skip records surrounding the bad |
---|
715 | record PER bad record in mapper. The number includes the bad record as well. |
---|
716 | To turn the feature of detection/skipping of bad records off, set the |
---|
717 | value to 0. |
---|
718 | The framework tries to narrow down the skipped range by retrying |
---|
719 | until this threshold is met OR all attempts get exhausted for this task. |
---|
720 | Set the value to Long.MAX_VALUE to indicate that framework need not try to |
---|
721 | narrow down. Whatever records(depends on application) get skipped are |
---|
722 | acceptable. |
---|
723 | </description> |
---|
724 | </property> |
---|
725 | |
---|
726 | <property> |
---|
727 | <name>mapred.skip.reduce.max.skip.groups</name> |
---|
728 | <value>0</value> |
---|
729 | <description> The number of acceptable skip groups surrounding the bad |
---|
730 | group PER bad group in reducer. The number includes the bad group as well. |
---|
731 | To turn the feature of detection/skipping of bad groups off, set the |
---|
732 | value to 0. |
---|
733 | The framework tries to narrow down the skipped range by retrying |
---|
734 | until this threshold is met OR all attempts get exhausted for this task. |
---|
735 | Set the value to Long.MAX_VALUE to indicate that framework need not try to |
---|
736 | narrow down. Whatever groups(depends on application) get skipped are |
---|
737 | acceptable. |
---|
738 | </description> |
---|
739 | </property> |
---|
740 | |
---|
741 | <!-- Job Notification Configuration --> |
---|
742 | |
---|
743 | <!-- |
---|
744 | <property> |
---|
745 | <name>job.end.notification.url</name> |
---|
746 | <value>http://localhost:8080/jobstatus.php?jobId=$jobId&jobStatus=$jobStatus</value> |
---|
747 | <description>Indicates url which will be called on completion of job to inform |
---|
748 | end status of job. |
---|
749 | User can give at most 2 variables with URI : $jobId and $jobStatus. |
---|
750 | If they are present in URI, then they will be replaced by their |
---|
751 | respective values. |
---|
752 | </description> |
---|
753 | </property> |
---|
754 | --> |
---|
755 | |
---|
756 | <property> |
---|
757 | <name>job.end.retry.attempts</name> |
---|
758 | <value>0</value> |
---|
759 | <description>Indicates how many times hadoop should attempt to contact the |
---|
760 | notification URL </description> |
---|
761 | </property> |
---|
762 | |
---|
763 | <property> |
---|
764 | <name>job.end.retry.interval</name> |
---|
765 | <value>30000</value> |
---|
766 | <description>Indicates time in milliseconds between notification URL retry |
---|
767 | calls</description> |
---|
768 | </property> |
---|
769 | |
---|
770 | <!-- Proxy Configuration --> |
---|
771 | <property> |
---|
772 | <name>hadoop.rpc.socket.factory.class.JobSubmissionProtocol</name> |
---|
773 | <value></value> |
---|
774 | <description> SocketFactory to use to connect to a Map/Reduce master |
---|
775 | (JobTracker). If null or empty, then use hadoop.rpc.socket.class.default. |
---|
776 | </description> |
---|
777 | </property> |
---|
778 | |
---|
779 | <property> |
---|
780 | <name>mapred.task.cache.levels</name> |
---|
781 | <value>2</value> |
---|
782 | <description> This is the max level of the task cache. For example, if |
---|
783 | the level is 2, the tasks cached are at the host level and at the rack |
---|
784 | level. |
---|
785 | </description> |
---|
786 | </property> |
---|
787 | |
---|
788 | <property> |
---|
789 | <name>mapred.queue.names</name> |
---|
790 | <value>default</value> |
---|
791 | <description> Comma separated list of queues configured for this jobtracker. |
---|
792 | Jobs are added to queues and schedulers can configure different |
---|
793 | scheduling properties for the various queues. To configure a property |
---|
794 | for a queue, the name of the queue must match the name specified in this |
---|
795 | value. Queue properties that are common to all schedulers are configured |
---|
796 | here with the naming convention, mapred.queue.$QUEUE-NAME.$PROPERTY-NAME, |
---|
797 | for e.g. mapred.queue.default.submit-job-acl. |
---|
798 | The number of queues configured in this parameter could depend on the |
---|
799 | type of scheduler being used, as specified in |
---|
800 | mapred.jobtracker.taskScheduler. For example, the JobQueueTaskScheduler |
---|
801 | supports only a single queue, which is the default configured here. |
---|
802 | Before adding more queues, ensure that the scheduler you've configured |
---|
803 | supports multiple queues. |
---|
804 | </description> |
---|
805 | </property> |
---|
806 | |
---|
807 | <property> |
---|
808 | <name>mapred.acls.enabled</name> |
---|
809 | <value>false</value> |
---|
810 | <description> Specifies whether ACLs are enabled, and should be checked |
---|
811 | for various operations. |
---|
812 | </description> |
---|
813 | </property> |
---|
814 | |
---|
815 | <property> |
---|
816 | <name>mapred.queue.default.acl-submit-job</name> |
---|
817 | <value>*</value> |
---|
818 | <description> Comma separated list of user and group names that are allowed |
---|
819 | to submit jobs to the 'default' queue. The user list and the group list |
---|
820 | are separated by a blank. For e.g. alice,bob group1,group2. |
---|
821 | If set to the special value '*', it means all users are allowed to |
---|
822 | submit jobs. |
---|
823 | </description> |
---|
824 | </property> |
---|
825 | |
---|
826 | <property> |
---|
827 | <name>mapred.queue.default.acl-administer-jobs</name> |
---|
828 | <value>*</value> |
---|
829 | <description> Comma separated list of user and group names that are allowed |
---|
830 | to delete jobs or modify job's priority for jobs not owned by the current |
---|
831 | user in the 'default' queue. The user list and the group list |
---|
832 | are separated by a blank. For e.g. alice,bob group1,group2. |
---|
833 | If set to the special value '*', it means all users are allowed to do |
---|
834 | this operation. |
---|
835 | </description> |
---|
836 | </property> |
---|
837 | |
---|
838 | <property> |
---|
839 | <name>mapred.job.queue.name</name> |
---|
840 | <value>default</value> |
---|
841 | <description> Queue to which a job is submitted. This must match one of the |
---|
842 | queues defined in mapred.queue.names for the system. Also, the ACL setup |
---|
843 | for the queue must allow the current user to submit a job to the queue. |
---|
844 | Before specifying a queue, ensure that the system is configured with |
---|
845 | the queue, and access is allowed for submitting jobs to the queue. |
---|
846 | </description> |
---|
847 | </property> |
---|
848 | |
---|
849 | <property> |
---|
850 | <name>mapred.tasktracker.indexcache.mb</name> |
---|
851 | <value>10</value> |
---|
852 | <description> The maximum memory that a task tracker allows for the |
---|
853 | index cache that is used when serving map outputs to reducers. |
---|
854 | </description> |
---|
855 | </property> |
---|
856 | |
---|
857 | <property> |
---|
858 | <name>mapred.merge.recordsBeforeProgress</name> |
---|
859 | <value>10000</value> |
---|
860 | <description> The number of records to process during merge before |
---|
861 | sending a progress notification to the TaskTracker. |
---|
862 | </description> |
---|
863 | </property> |
---|
864 | |
---|
865 | <property> |
---|
866 | <name>mapred.reduce.slowstart.completed.maps</name> |
---|
867 | <value>0.05</value> |
---|
868 | <description>Fraction of the number of maps in the job which should be |
---|
869 | complete before reduces are scheduled for the job. |
---|
870 | </description> |
---|
871 | </property> |
---|
872 | |
---|
873 | </configuration> |
---|