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https://issues.apache.org/jira/browse/CASSANDRA-8880?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14367865#comment-14367865
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Chris Lohfink commented on CASSANDRA-8880:
------------------------------------------
This wont capture top level row/range tombstones:
{code}
create keyspace test WITH replication = {'class': 'SimpleStrategy',
'replication_factor': 1}
create TABLE test.blarg (key text, value text, PRIMARY KEY (key));
create table test.cf ( key text, col text, val text, PRIMARY KEY (key, col));
================
INSERT INTO test.blarg (key, value) VALUES ('1', '2');
DELETE FROM test.blarg WHERE key = '1';
INSERT INTO test.cf (key, col, val) VALUES ('1', '2', '3');
delete from test.cf WHERE key = '1' AND col = '2';
{code}
for example wont be counted at all since the columnfamily iterable would be
empty.
might be hard to even know how many tombstones the range/row deletions will
cause on reads without doing one so I think the tombstones scanned metric will
still be pretty important.
> Add metrics to monitor the amount of tombstones created
> -------------------------------------------------------
>
> Key: CASSANDRA-8880
> URL: https://issues.apache.org/jira/browse/CASSANDRA-8880
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Michaël Figuière
> Assignee: Lyuben Todorov
> Priority: Minor
> Labels: metrics
> Fix For: 2.1.4
>
> Attachments: cassandra-2.1-8880.patch
>
>
> AFAIK there's currently no way to monitor the amount of tombstones created on
> a Cassandra node. CASSANDRA-6057 has made it possible for users to figure out
> how many tombstones are scanned at read time, but in write mostly workloads,
> it may not be possible to realize if some inappropriate queries are
> generating too many tombstones.
> Therefore the following additional metrics should be added:
> * {{writtenCells}}: amount of cells that have been written
> * {{writtenTombstoneCells}}: amount of tombstone cells that have been written
> Alternatively these could be exposed as a single gauge such as
> {{writtenTombstoneCellsRatio}}.
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