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https://issues.apache.org/jira/browse/HIVE-26704?focusedWorklogId=844490&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-844490
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ASF GitHub Bot logged work on HIVE-26704:
-----------------------------------------

                Author: ASF GitHub Bot
            Created on: 09/Feb/23 03:59
            Start Date: 09/Feb/23 03:59
    Worklog Time Spent: 10m 
      Work Description: SourabhBadhya commented on code in PR #3576:
URL: https://github.com/apache/hive/pull/3576#discussion_r1100958004


##########
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/txn/CompactionTxnHandler.java:
##########
@@ -1577,24 +1590,20 @@ public long findMinTxnIdSeenOpen() throws MetaException 
{
             }
             minOpenTxn = rs.getLong(1);
             if (rs.wasNull()) {
-              minOpenTxn = -1L;
+              minOpenTxn = Long.MAX_VALUE;

Review Comment:
   Ok





Issue Time Tracking
-------------------

    Worklog Id:     (was: 844490)
    Time Spent: 2h 10m  (was: 2h)

> Cleaner shouldn't be blocked by global min open txnId
> -----------------------------------------------------
>
>                 Key: HIVE-26704
>                 URL: https://issues.apache.org/jira/browse/HIVE-26704
>             Project: Hive
>          Issue Type: Task
>            Reporter: Denys Kuzmenko
>            Assignee: Denys Kuzmenko
>            Priority: Major
>              Labels: pull-request-available
>          Time Spent: 2h 10m
>  Remaining Estimate: 0h
>
> *Single transaction blocks cluster-wide Cleaner operations*
> Currently, if there is a single long-running transaction that can prevent the 
> Cleaner to clean up any tables. This causes file buildup in tables, which can 
> cause performance penalties when listing the directories (note that the 
> compaction is not blocked by this, so unnecessary data is not read, but the 
> files remain there which causes performance penalty). 
> We can reduce the protected files from the open transaction if we have 
> query-table correlation data stored in the backend DB, but this change will 
> need the current method of recording that detail to be revisited. 
> The naive and somewhat backward-compatible approach is to capture the 
> minOpenWriteIds per table. It involves a non-mutation operation (as in, there 
> is no need for the HMS DB to wait for another user’s operation to record it). 
> This does spew data writes into the HMS backend DB, but this is a blind 
> insert operation that can be group-committed across many users. 



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