# Amazon EMR 6.15.0 - Tez release notes
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## Amazon EMR 6.15.0 - Tez changes
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| Type | Description | 
| --- | --- | 
| Feature | [TEZ-4397](https://issues.apache.org/jira/browse/TEZ-4397): Open Tez Input splits asynchronously | 
| Upgrade | [TEZ-4493](https://issues.apache.org/jira/browse/TEZ-4493): Upgrade Apache Hadoop to 3.3.6 | 

**Amazon EMR 6.15.0 - Tez known issues**
+ **Pig jobs running on Tez** – In clusters with SSL enabled running EMR version 6.9.0 to 7.0.0, there is a known issue where Pig jobs running on Tez fail with *SSLHandshakeException*. This is related to the open-source issue [TEZ-4096](https://issues.apache.org/jira/browse/TEZ-4096), which was introduced with the Tez upgrade to version 0.10.2 in EMR 6.9.0. The issue requires SSL-related configurations to be passed from the client side (Pig).

  **Fix version:** – EMR 7.1.0

  **Workaround** – Add the following SSL configuration to tez-site.xml:

  ```
  <property>
      <name>ssl.client.truststore.location</name>
      <value>{SSL_TRUSTSTORE_LOCATION}</value>
  </property>
  ```
+ **Tez DAG cleanup issue (EMR 6.11.0 - EMR 7.2.0)** – In clusters with SSL enabled running EMR versions 6.11.0 to 7.2.0, there is a known issue where *SSLHandshakeException* occurs in TEZ Application Master (AM) during the DAG cleanup phase. This happens when attempting to delete intermediate shuffle data from remote nodes over HTTPS after query completion, not during the query execution. The issue occurs because Tez AM cannot read the relevant **trustStore** configuration when calling the shuffle handler service endpoint. However this affects only the cleaning up of shuffle data during DAG cleanup, the application(AM) level cleanup happens anyways and cleans up any lingering shuffle data. So this doesn’t lead to shuffle data accumulation. 

  **Fix version:** – EMR 7.3.0

  **Workaround** – Add the following SSL configuration to tez-site.xml:

  ```
  <property>
      <name>ssl.client.truststore.location</name>
      <value>{SSL_TRUSTSTORE_LOCATION}</value>
  </property>
  ```

## Amazon EMR 6.15.0 - Tez features
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+ **[Tez asynchronous split opening](tez-configure.md#tez-configure-async)** – Amazon EMR 6.15.0 introduces configurations that you can specify to asynchronously open the input splits in a Tez *grouped split*. The feature was initiated by [TEZ-4397](https://issues.apache.org/jira/browse/TEZ-4397), but had regressions in OSS Hive. Amazon EMR Hive fixed the regressions and additional bugs in Hive ACID table. This improvement results in faster performance of read queries when there are a large number of input splits in a single Tez grouped split. For more information, see [Tez asynchronous split opening](tez-configure.md#tez-configure-async).