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https://issues.apache.org/jira/browse/CASSANDRA-6998?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13968457#comment-13968457
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Muhammad Adel commented on CASSANDRA-6998:
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Deleting undelivered tombstones can introduce problems with consistency. I
don't think a hinted handoff row should ever be deleted before delivery even if
it was a tombstone.
The exception is thrown when the number of deleted columns in the query result
exceed the tombstonefailurethreshold.
This can be solved using in two ways:
1-Instead of just removing the tombstones by compacting the table, we can
decrease the page size when catching the exception and then try to perform the
hinted handoff again.This will decrease the number of deleted columns below the
tombstonefailurethreshold.
2-a better design choice in my opinion is to use another type of queries, one
that gets all rows with a given size regardless of being a live row or
not.SliceQueries are not the suitable type for this task since hinted handoff
deliver doesn't care for the status of the given row.
> HintedHandoff - expired hints may block future hints deliveries
> ---------------------------------------------------------------
>
> Key: CASSANDRA-6998
> URL: https://issues.apache.org/jira/browse/CASSANDRA-6998
> Project: Cassandra
> Issue Type: Bug
> Components: Core
> Environment: - cluster of two DCs: DC1, DC2
> - keyspace using NetworkTopologyStrategy (replication factors for both DCs)
> - heavy load (write:read, 100:1) with LOCAL_QUORUM using Java driver setup
> with DC awareness, writing to DC1
> Reporter: Scooletz
> Labels: HintedHandoff, TTL
> Fix For: 2.0.3
>
>
> For tests purposes, DC2 was shut down for 1 day. The _hints_ table was filled
> with millions of rows. Now, when _HintedHandOffManager_ tries to
> _doDeliverHintsToEndpoint_ it queries the store with
> QueryFilter.getSliceFilter which counts deleted (TTLed) cells and throws
> org.apache.cassandra.db.filter.TombstoneOverwhelmingException.
> Throwing this exception stops the manager from running compaction as it is
> run only after successful handoff. This leaves the HH practically disabled
> till administrator runs truncateAllHints.
> Wouldn't it be nicer if on
> org.apache.cassandra.db.filter.TombstoneOverwhelmingException run compaction?
> That would remove TTLed hints leaving whole HH mechanism in a healthy state.
> The stacktrace is:
> {quote}
> org.apache.cassandra.db.filter.TombstoneOverwhelmingException
> at
> org.apache.cassandra.db.filter.SliceQueryFilter.collectReducedColumns(SliceQueryFilter.java:201)
> at
> org.apache.cassandra.db.filter.QueryFilter.collateColumns(QueryFilter.java:122)
> at
> org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:80)
> at
> org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:72)
> at
> org.apache.cassandra.db.CollationController.collectAllData(CollationController.java:297)
> at
> org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:53)
> at
> org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:1487)
> at
> org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1306)
> at
> org.apache.cassandra.db.HintedHandOffManager.doDeliverHintsToEndpoint(HintedHandOffManager.java:351)
> at
> org.apache.cassandra.db.HintedHandOffManager.deliverHintsToEndpoint(HintedHandOffManager.java:309)
> at
> org.apache.cassandra.db.HintedHandOffManager.access$300(HintedHandOffManager.java:92)
> at
> org.apache.cassandra.db.HintedHandOffManager$4.run(HintedHandOffManager.java:530)
> at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
> at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
> at java.lang.Thread.run(Thread.java:722)
> {quote}
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