awitt

3 ms·

1. 1.▲
   by awitt 2y ago

   Yes, that's true. And not even ClickHouse considers their MergeTree engine to be an LSM-tree (see https://github.com/ClickHouse/ClickHouse/blob/bfc0260f359a0c... ). That doesn't make it wrong, or a
2. 2.▲
   by awitt 2y ago

   I actually think you're describing a WAL.
3. 3.▲
   by awitt 2y ago

   The original purpose of an LSM-tree is to take I/O off the critical path of a write (there are other reasons to use them though, for example reducing space amplification). I would argue that by definition an LSM-tree buffers committed
4. 4.▲
   by awitt 2y ago

   LSM-trees do need a WAL. The entire idea of LSM-trees is that writes are buffered in memory and written out all at once. But a particular write doesn't wait for the memtable to be flushed. For that reason you still need a WAL (there