This patch makes makes major compaction aware of time buckets
for TWCS. That means that calling a major compaction with TWCS
will not bundle all SSTables together, but rather split them
based on their timestamps.
There are two motivations for this work:
1. Telling users not to ever major compact is easier said than
done: in practice due to a variety of circumstances it might
end up being done in which case data will have a hard time
expiring later.
2. We are about to start working with offstrategy compactions,
which are compactions that work in parallel with the main
compactions. In those cases we may be converting SSTables from
one format to another and it might be necessary to split a single
big STCS SSTable into something that TWCS expects
With the motivation out of the way, let's talk about the implementation:
The implementation is quite simple and builds upon the previous patches.
It simply specializes the interposer implementation for regular compaction
with a table-specific interposer.
Fixes#1431
Signed-off-by: Glauber Costa <glauber@scylladb.com>
098b215b0d