commitlog_archiving.properties contains a property called "precision" which is by default set to MICROSECONDS (1). However, we have this formatter for restore_point_in_time (2). The restoration time will ever be evaluated to milliseconds here (3) and it loses anything beyond seconds. When restore time is e.g. 2012:04:31 20:43:12.123, the formatter will remove .123 and that is converted to milliseconds via .getTime(). Then it goes here (4), it will convert maxTimestamp() to milliseconds and compare it to restoreTarget which is in milliseconds too but we dropped the milliseconds resolution because of the formatter.
CASSANDRA-19448 tries to solve this by removing precision property and supporting resolutions in restore_point_in_time down to microseconds but I am not sure we can remove it just like that. Can we? What confuses me is the comment here: # precision of the timestamp used in the inserts (MILLISECONDS, MICROSECONDS, ...) precision=MICROSECONDS _used in the inserts_ ? What does it mean exactly? For example, when we use USING TIMESTAMP, isn't that in microseconds already? It looks like it was (or it is?) possible to insert into Cassandra with different resolutions so this property was introduced to match what resolution we were writing the inserts with internally? If maxTimestamp() on PartitionUpdate (4) is ever going to return resolution in microseconds, we can get rid of that, but if it ever returns something else (like in milliseconds), we can not, right? (without reflecting that in precision). Under what circumstances it would be returned in anything but in microseconds? PartitionUpdate.maxTimestamp() contains e.g. long maxTimestamp = deletionInfo.maxTimestamp(); That calls partitionDeletion.markedForDeleteAt() where its Javadoc says (5) - "A timestamp (typically in microseconds since the unix epoch, although this is not enforced)". Is this still relevant 5.x times? (1) https://github.com/apache/cassandra/blob/trunk/conf/commitlog_archiving.properties#L57 (2) https://github.com/apache/cassandra/blob/trunk/conf/commitlog_archiving.properties#L40 (3) https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/db/commitlog/CommitLogArchiver.java#L128 (4) https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/db/commitlog/CommitLogReplayer.java#L498 (5) https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/db/DeletionTime.java#L82-L86
