Hadoop streaming with Python
Want to write a Hadoop program in less than 5 minutes? Get in here for a quick check on how it’s done. We use Python and Hadoop streaming to complete the task.
Tagged: hadoop
Cleanup hdfs directory having too many files and directories
At times some directories on hdfs has too many inodes (files and folders) and it is really hard to delete. Some instances also lead to out of memory (OOM) errors such as the following error, INFO retry.RetryInvocationHandler: java.io.IOException: com.google.protobuf.ServiceException: java.lang.OutOfMemoryError:...
Extract query time from hiveserver2 Interactive log
Got in a situation where you were asked to extract hive queries and the time they took to execute? Steps On log files run below 2 extracts awk ‘match($0, “^([^ ]+).*Completed executing command\\(queryId=([0-9a-z_-]+)\\); Time taken: (.*)”, a) {print “COMPLETE\t” a[1]...
HDFS data sizing
Below is data storage estimator based on message size and throughput. Input HDFS replication and the amount of data end users will generate over time using raw data. Hope this helps you. Data calculator Message size in bytes Message per...
snakebite – Python HDFS client
Source: https://snakebite.readthedocs.io/en/latest/client.html Example: >>> from snakebite.client import Client >>> client = Client(“localhost”, 8020, use_trash=False) >>> for x in client.ls([‘/’]): … print x Warning Many methods return generators, which mean they need to be consumed to execute! Documentation will explicitly...
Hadoop like a PRO
Lookup yarn queue of a user from bash This bash function will lookup capacity scheduler XML and return queues for the user getYarnQueue() { grep $1 -B 1 /etc/hadoop/conf/capacity-scheduler.xml | awk -F’.’ ‘/name/{print $(NF-1)}’ } Works on Hortonworks HDP. Usage:...
Hive msck repair not working
Okay, so msck repair is not working and you saw something as below, 0: jdbc:hive2://hive_server:10000> msck repair table mytable; Error: Error while processing statement: FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask (state=08S01,code=1) It seems to appear because of higher...
DistCp Between HA Clusters
Source: https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.6.1/bk_administration/content/distcp_between_ha_clusters.html DistCp Between HA Clusters To copy data between HA clusters, use the dfs.internal.nameservices property in the hdfs-site.xml file to explicitly specify the name services belonging to the local cluster, while continuing to use the dfs.nameservices property to specify all of the name services in...
Hive export to CSV
Bash function to export Hive table data to local CSV file Usage: hive_export_csv <db.table> <output.csv> [queue] Recommendation: Add to .bash_profile hive_export_csv () { if [ -z “$2” ]; then echo “Bad arguments. Usage: ${FUNCNAME[0]} <db.table> <output.csv> [queue]” else uuid=$(uuidgen)...
HiveAccessControlException Permission denied user [user] does not have [WRITE] privilege on …
Source: https://community.hortonworks.com/questions/112754/insert-overwrite-directory-beeline.html Error Error: Error while compiling statement: FAILED: HiveAccessControlException Permission denied: user [user] does not have [WRITE] privilege on [/tmp/*] (state=42000,code=40000) The above error appears, even though you’ve setup ranger policies, hdfs policies are set up. You’ve checked everything and...
