[
https://issues.apache.org/jira/browse/CASSANDRA-18134?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17688370#comment-17688370
]
Jacek Lewandowski commented on CASSANDRA-18134:
-----------------------------------------------
Thank you [~cscotta] for taking a look. This PR is against master so it will go
with the next Cassandra release which as I've heard is 5.0, so I don't think
there is an issue here.
For the tests you are suggesting - what kind of tests you have in mind? To me,
the code does not introduce any new functionality but changes in existing read
path which should result in performance improvements (which has been actually
proven in a couple of test cases where the expected number of iterated sstables
was reduced). Perhaps it makes sense to run existing fuzz tests which verify
the read path. I don't know if we have such tests and I don't know how to run
tests in Harry. If such tests do not exist yet, I'm happy to open a separate
ticket to implement them as it would be a task on its own.
> Improve handling of min/max clustering in sstable
> -------------------------------------------------
>
> Key: CASSANDRA-18134
> URL: https://issues.apache.org/jira/browse/CASSANDRA-18134
> Project: Cassandra
> Issue Type: Improvement
> Components: Local/SSTable
> Reporter: Jacek Lewandowski
> Assignee: Jacek Lewandowski
> Priority: Normal
> Fix For: 5.x
>
>
> This patch improves the following things:
> # SSTable metadata will store a covered slice instead of min/max clusterings.
> The difference is that for slices there is available the type of a bound
> rather than just a clustering. In particular it will provide the information
> whether the lower and upper bound of an sstable is opened or closed.
> # SSTable metadata will store a flag whether the SSTable contains any
> partition level deletions or not
> # The above two changes required to introduce a new major format for SSTables
> - {{oa}}
> # Single partition read command makes use of the above changes. In particular
> an sstable can be skipped when it does not intersect with the column filter,
> does not have partition level deletions and does not have statics; In case
> there are partition level deletions, but the other conditions are satisfied,
> only the partition header needs to be accessed (tests attached)
> # Skipping sstables assuming those three conditions are satisfied has been
> implemented also for partition range queries (tests attached). Also added
> minor separate statistics to record the number of accessed sstables in
> partition reads because now not all of them need to be accessed. That
> statistics is also needed in tests to confirm skipping.
> # Artificial lower bound marker is now an object on its own and is not
> implemented as a special case of range tombstone bound. Instead it sorts
> right before the lowest available bound in the data
> # Extended the lower bound optimization usage due the 1 and 2
> # Do not initialize iterator just to get a cached partition and associated
> columns index. The purpose of using lower bound optimization was to avoid
> opening an iterator of an sstable if possible.
> See also CASSANDRA-14861
> The changes in this patch include work of [~blambov], [~slebresne],
> [~jakubzytka] and [~jlewandowski]
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org
For additional commands, e-mail: commits-h...@cassandra.apache.org
