c7c5817808
When purging regular tombstone consult the min_live_timestamp, if available. This is safe since we don't need to protect dead data from resurrection, as it is already dead. For shadowable_tombstones, consult the min_memtable_live_row_marker_timestamp, if available, otherwise fallback to the min_live_timestamp. If we see in a view table a shadowable tombstone with time T, then in any row where the row marker's timestamp is higher than T the shadowable tombstone is completely ignored and it doesn't hide any data in any column, so the shadowable tombstone can be safely purged without any effect or risk resurrecting any deleted data. In other words, rows which might cause problems for purging a shadowable tombstone with time T are rows with row markers older or equal T. So to know if a whole sstable can cause problems for shadowable tombstone of time T, we need to check if the sstable's oldest row marker (and not oldest column) is older or equal T. And the same check applies similarly to the memtable. If both extended timestamp statistics are missing, fallback to the legacy (and inaccurate) min_timestamp. Fixes scylladb/scylladb#20423 Fixes scylladb/scylladb#20424 > [!NOTE] > no backport needed at this time > We may consider backport later on after given some soak time in master/enterprise > since we do see tombstone accumulation in the field under some materialized views workloads Closes scylladb/scylladb#20446 * github.com:scylladb/scylladb: cql-pytest: add test_compaction_tombstone_gc sstable_compaction_test: add mv_tombstone_purge_test sstable_compaction_test: tombstone_purge_test: test that old deleted data do not inhibit tombstone garbage collection sstable_compaction_test: tombstone_purge_test: add testlog debugging sstable_compaction_test: tombstone_purge_test: make_expiring: use next_timestamp sstable, compaction: add debug logging for extended min timestamp stats compaction: get_max_purgeable_timestamp: use memtable and sstable extended timestamp stats compaction: define max_purgeable_fn tombstone: can_gc_fn: move declaration to compaction_garbage_collector.hh sstables: scylla_metadata: add ext_timestamp_stats compaction_group, storage_group, table_state: add extended timestamp stats getters sstables, memtable: track live timestamps memtable_encoding_stats_collector: update row_marker: do nothing if missing
ScyllaDB Documentation
This repository contains the source files for ScyllaDB Open Source documentation.
- The
devfolder contains developer-oriented documentation related to the ScyllaDB code base. It is not published and is only available via GitHub. - All other folders and files contain user-oriented documentation related to ScyllaDB Open Source and are sources for docs.scylladb.com.
To report a documentation bug or suggest an improvement, open an issue in GitHub issues for this project.
To contribute to the documentation, open a GitHub pull request.
Key Guidelines for Contributors
- Follow the ScyllaDB Style Guide.
- The user documentation is written in reStructuredText (RST) - a plaintext markup language similar to Markdown. If you're not familiar with RST, see ScyllaDB RST Examples.
- The developer documentation is written in Markdown. See Basic Markdown Syntax for reference.
Creating Knowledge Base Articles
The kb/ directory holds source files for knowledge base articles in the Knowledge Base section of the ScyllaDB documentation.
The kb/kb_common subdirectory contains a template for knowledge base articles to help you create new articles.
To create a new knowledge base article (KB):
- Copy the
kb-article-template.rstfile from/kb/kb_commonto/kband rename it with a unique name. - Open the new file and fill in the required information.
- Remove what is not needed.
- Run
make previewto build the docs and preview them locally. - Send a PR with "KB" in its title.
Building User Documentation
Prerequisites
- Python 3. Check your version with
$ python --version. - poetry 1.12 or later
- make
Mac OS X
You must have a working Homebrew in order to install the needed tools.
You also need the standard utility make.
Check if you have these two items with the following commands:
brew help
make -h
Linux Distributions
Building the user docs should work out of the box on most Linux distributions.
Windows
Use "Bash on Ubuntu on Windows" for the same tools and capabilities as on Linux distributions.
Building the Docs
- Run
make previewto build the documentation. - Preview the built documentation locally at http://127.0.0.1:5500/.
Cleanup
You can clean up all the build products and auto-installed Python stuff with:
make pristine
Information for Contributors
If you are interested in contributing to Scylla docs, please read the Scylla open source page at http://www.scylladb.com/opensource/ and complete a Scylla contributor agreement if needed. We can only accept documentation pull requests if we have a contributor agreement on file for you.
Third-party Documentation
-
Do any copying as a separate commit. Always commit an unmodified version first and then do any editing in a separate commit.
-
We already have a copy of the Apache license in our tree, so you do not need to commit a copy of the license.
-
Include the copyright header from the source file in the edited version. If you are copying an Apache Cassandra document with no copyright header, use:
This document includes material from Apache Cassandra.
Apache Cassandra is Copyright 2009-2014 The Apache Software Foundation.