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https://issues.apache.org/jira/browse/KYLIN-5308?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17640513#comment-17640513
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ASF GitHub Bot commented on KYLIN-5308:
---------------------------------------

hit-lacus commented on code in PR #2039:
URL: https://github.com/apache/kylin/pull/2039#discussion_r1034513420


##########
src/core-common/src/test/java/org/apache/kylin/common/persistence/metadata/FileEpochStoreTest.java:
##########
@@ -15,15 +15,14 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.kylin.common.persistence.metadata.epochstore;
+package org.apache.kylin.common.persistence.metadata;
 
 import org.junit.jupiter.api.BeforeEach;
 
-public final class FileEpochStoreTest extends AbstractEpochStoreTest {

Review Comment:
   Why remove `public`?





> The old transaction is not interrupted when Epoch renew retry
> -------------------------------------------------------------
>
>                 Key: KYLIN-5308
>                 URL: https://issues.apache.org/jira/browse/KYLIN-5308
>             Project: Kylin
>          Issue Type: Bug
>            Reporter: Jiale He
>            Assignee: Jiale He
>            Priority: Critical
>             Fix For: 5.0-alpha
>
>         Attachments: KYLIN-5308 Epoch Renew 事务超时 Design.pdf, 
> image-2022-11-28-16-32-00-356.png, image-2022-11-29-14-29-31-681.png
>
>
> kylin fails to write data to the new transaction because the old transaction 
> is not interrupted during the Renew Epoch Retry. As a result, Kylin loses the 
> epoch.
>  
> When Epoch Renew occurs, the write to the database times out and tries again. 
> As the old transaction is not rolled back during the retry, the old 
> transaction is successfully written to the database and MVCC+1 occurs. When a 
> new transaction writes to the database, it will check the MVCC. If the 
> detection fails, kylin will think that the Epoch is lost.
> !image-2022-11-28-16-32-00-356.png!
>  
> See attachment for RC and Fix Design:  `KYLIN-5308 Epoch Renew 事务超时 
> Design.pdf`
>  
>  
>  



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