Known Issues and Restrictions
- Sqoop importing data into Hive fails when the entire cluster is configured to use Tez.
- This is because of Sqoop's incompatibility with Tez.
Workaround: Do not configure the entire cluster to use Tez.
- Percentage sampling is not supported in
org.apache.hadoop.hive.ql.io.HiveInputFormat
. Hive uses
org.apache.hadoop.hive.ql.io.HiveInputFormat
by default and so queries like'SELECT * FROM tablename TABLESAMPLE(20 percent);'
will not work for Hive on Tez.Workaround: Instead of
org.apache.hadoop.hive.ql.io.HiveInputFormat
, useorg.apache.hadoop.hive.ql.io.CombineHiveInputFormat
.To change input format, do one of the following:
- Set
hive.tez.input.format
in hive shell. For example:hive> set hive.tez.input.format=org.apache.hadoop.hive.ql.io.CombineHiveInputFormat;
- Add
org.apache.hadoop.hive.ql.io.CombineHiveInputFormat
tohive-site.xml
file. For example:<property> <name>hive.tez.input.format</name> <value>org.apache.hadoop.hive.ql.io.CombineHiveInputFormat</value> </property>
- Set
- Hive on Tez does not work well with Sequence Files Schema changes
- TEZ-2741
- Limitations with common joins
- HIVE-11693: The CommonMergeJoinOperator only sets big table position when it has inputs for big table. If the input is empty, the method is not called.
- HiveServer2 on Tez doesn't support concurrent queries within one session
- HIVE-9223: When multiple queries are submitted in the same HS2 session concurrently, some queries fail with an error.
- Tez upgrade issues
- No support for preserving configuration from EEP-5.0.0 and EEP-4.1.1 (ECO-1803) to EEP-6.0.0(1808) or EEP-5.0.1(1808) on Ubuntu.
- No support for preserving Tomcat configuration from previous EEPs to EEP-6.0.0 (1808).
- You should manually stop the Tomcat service and delete the tomcat folder as a
precondition if you are updating or upgrading Tez from the following EEPs:
EEP-4.0.0
EEP-4.1.0
- Tez shuffle SSL encryption issue
- During a shuffle phase, the
javax.net.ssl.SSLException
error could occur on a multi-node cluster due to insufficient Tez shuffle SSL encryption configuration, see Tez Shuffle for a solution.