Table 1 Hadoop’s basic configuration parameters
From: A Pareto-based scheduler for exploring cost-performance trade-offs for MapReduce workloads
Parameter | Description | Default |
|---|---|---|
value | ||
Mapred.reduce.tasks | Number of reduce tasks | 1 |
Io.sort.mb | Map buffer size in MB | 100 |
Io.sort.record.percent | The percentage of the map buffer’s | |
size used for metadata | 0.05 | |
Io.sort.spill.percent | Threshold in the map buffer’s size | |
that if exceeded in-memory data | ||
are stored in local files | 0.80 | |
Dfs.block.size | HDFS block size, determines the | |
number of map tasks | 128 m |