If you actually have splittable files you can set the following setting to create more splits:
mapred.max.split.size appropriately. Thanks Vaibhav From: Daniel,Wu [mailto:hadoop...@163.com] Sent: Tuesday, August 23, 2011 6:51 AM To: hive Subject: Why a sql only use one map task? I run the following simple sql select count(*) from sales; And the job information shows it only uses one map task. The underlying hadoop has 3 data/data nodes. So I expect hive should kick off 3 map tasks, one on each task nodes. What can make hive only run one map task? Do I need to set something to kick off multiple map task? in my config, I didn't change hive config.
