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ScyllaDB SSTable - 2.x¶
Sorted Strings Table (SSTable) is the persistent file format used by ScyllaDB and Apache Cassandra. SSTable is saved as a persistent, ordered, immutable set of files on disk.
Immutable means SSTables are never modified; they are created by a MemTable flush and are deleted by a compaction.
The location of ScyllaDB SSTables is specified in scylla.yaml data_file_directories parameter (default location: /var/lib/scylla/data).
SSTable 3.x is more efficient and requires less disk space than the SSTable 2.x.
For more information on each of the SSTable formats, see below:
SSTable Version Support¶
SSTable Version |
ScyllaDB Version |
|---|---|
3.x ( |
2025.4 and above |
3.x ( |
2022.2 and above |
3.x ( |
2021.1 |
The supported formats are
meandms.The
mdformat is used only when upgrading from an existing cluster usingmd. Thesstable_formatparameter is ignored if it is set tomd.Note: The
sstable_formatparameter specifies the SSTable format used for writes. The legacy SSTable formats (ka,la,mc) remain supported for reads, which is essential for restoring clusters from existing backups.
The ms Format: Trie-Based SSTable Index¶
The ms format introduces a trie-based SSTable index.
For a detailed description of the trie index format, see SSTable ms Index.
For more information about ScyllaDB 2.x SSTable formats, see below:
SSTable Compression - Deep dive into ScyllaDB/Apache Cassandra SSTable Compression
SSTable Data File - Deep dive into ScyllaDB/Apache Cassandra SSTable format
SSTable format in ScyllaDB - ScyllaDB SSTables are compatible to those in Apache Cassandra 2.1.8, but why there are more of them?
SSTable Interpretation - Deep dive into ScyllaDB/Apache Cassandra SSTable Interpretation in ScyllaDB
SSTable Summary File - Deep dive into ScyllaDB/Apache Cassandra SSTable Summary file format
Copyright
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