Live instructor-led & Self-paced Online Certification Training Courses (Big Data, Hadoop, Spark) › Forums › Hadoop › What is slot in Hadoop v1 Map-Reduce ? This topic contains 1 reply, has 1 voice, and was last updated by dfbdteam3 1 year, 6 months ago. Viewing 2 posts - 1 through 2 (of 2 total) Author Posts September 20, 2018 at 11:48 am #4698 dfbdteam3Moderator What are the slots? how many types or slots are there? What are the issues with the slot based mechanism ? why it was removed from Hadoop 2 ? September 20, 2018 at 11:49 am #4699 dfbdteam3Moderator Each Map Reduce Jobs are split into task and Task tracker runs each task on a fixed number of map and reduce slots inside a data node based on a static configuration. In Hadoop 1.0 we need to specify in mapred-site.xml the following parameter to Configure the number of map slots and reduce slots mapreduce.tasktracker.map.tasks.maximum mapreduce.tasktracker.reduce.tasks.maximum The Following are the problem with Slot Slots are wasted, anytime the cluster workload does not fit the static configuration. In a slot-based model makes it hard for non-MapReduce applications to be scheduled appropriately. Jobs never leave their original slots and cannot be move to free slots. For more details about MapReduce Jobs, please refer: MapReduce Tutorial Author Posts Viewing 2 posts - 1 through 2 (of 2 total) You must be logged in to reply to this topic.