Scylla SSTable - 3.x¶

Sorted Strings Table (SSTable) is the persistent file format used by Scylla 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 Scylla SSTables is specified in scylla.yaml data_file_directories parameter (default location: /var/lib/scylla/data).

SSTable 3.0 (mc format) is more efficient and requires less disk space than the SSTable 2.x. SSTable version support is as follows:

• In Scylla 3.1 and above, mc format is enabled by default.

• In Scylla 3.0, mc format is disabled by default and can be enabled by adding the enable_sstables_mc_format parameter as ‘true’ in scylla.yaml file.

For example:

enable_sstables_mc_format: true

For more information on Scylla 3.x SSTable formats, see below:

• SSTable 3.0 Data File Format

• SSTable 3.0 Statistics

• SSTable 3.0 Summary

• SSTable 3.0 Index

• SSTable 3.0 Format in Scylla