This short report brings to light some interesting commits to scylladb.git master from the last week. Commits in the e8efcae9919..fb6eebc3831 range are covered.
There were 124 non-merge commits from 25 authors in that period. Some notable commits:
The similarity_cosine() CQL function, used for vector search, now returns NaN instead of an error when one of the inputs is the zero vector.
There is a new nodetool cluster snapshot command that takes a global snapshot. Unlike nodetool snapshot that takes node-local snapshots, the new command snapshots the entire cluster and is not subject to races due to tablet migration.
The container image now packages the systemctl binary.
The metrics now expose a histogram of request and response sizes.
There is now a row-level time-to-live (TTL) feature in CQL. With row-level TTL, the expiration time for the entire row can be updated without reading the rest of the row, and expiration produces a Change Data Capture (CDC) entry.
ScyllaDB waits for the sstable count to drop below some threshold before flushing memtables, as an emergency stop to avoid flooding the system with new sstables. In some cases, ScyllaDB would stop flushing but not restart it later, leading to writes being completely stopped. This is now fixed.
The gossip-based topology code was removed. To upgrade to ScyllaDB 2026.2 or higher, one must switch to Raft topology before the upgrade.
See you in the next issue of last week in scylladb.git master!