cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Muhammad Adel (JIRA)" <>
Subject [jira] [Commented] (CASSANDRA-6998) HintedHandoff - expired hints may block future hints deliveries
Date Thu, 24 Apr 2014 09:03:15 GMT


Muhammad Adel commented on CASSANDRA-6998:

 Instead of ignoring tombstones when counting returned page size, and instead of ignoring
irrelevant data, deliver both relevant and Irrelevant columns. This will increase data consistency
when the recovering node was down for a time longer than the gc grace period.

To avoid performance problems, when choosing to return both relevant and irrelevant data,
the slice query filter will count the tombstones and irrelevant columns, compared to counting
live columns only in the ordinary case. The check for tombstone threshold is ignored in this
specific case.

Patch submitted.

> HintedHandoff - expired hints may block future hints deliveries
> ---------------------------------------------------------------
>                 Key: CASSANDRA-6998
>                 URL:
>             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
>         Attachments: 6998
> 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(
> 	at org.apache.cassandra.db.filter.QueryFilter.collateColumns(
> 	at org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(
> 	at org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(
> 	at org.apache.cassandra.db.CollationController.collectAllData(
> 	at org.apache.cassandra.db.CollationController.getTopLevelColumns(
> 	at org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(
> 	at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(
> 	at org.apache.cassandra.db.HintedHandOffManager.doDeliverHintsToEndpoint(
> 	at org.apache.cassandra.db.HintedHandOffManager.deliverHintsToEndpoint(
> 	at org.apache.cassandra.db.HintedHandOffManager.access$300(
> 	at org.apache.cassandra.db.HintedHandOffManager$
> 	at java.util.concurrent.ThreadPoolExecutor.runWorker(
> 	at java.util.concurrent.ThreadPoolExecutor$
> 	at
> {quote}

This message was sent by Atlassian JIRA

View raw message