replicated_deduplication_window
The number of most recently inserted blocks for which ClickHouse Keeper stores hash sums to check for duplicates. Possible values:- Any positive integer.
- 0 (disable deduplication)
replicated_deduplication_window blocks. The oldest hash sums are removed from
ClickHouse Keeper.
The hash sum covers the whole inserted block, so an insert is deduplicated only when its
entire data matches a previous insert (a retry), not per individual part.
A large number for replicated_deduplication_window slows down Inserts because more
entries need to be compared.
replicated_deduplication_window_for_async_inserts
Legacy setting retained for mixed-version rolling upgrades. New inserts deduplicate with the unified hash governed byreplicated_deduplication_window; this setting now only bounds how many
legacy async-insert hashes are kept in the async_blocks directory in ClickHouse Keeper, which is
still written by older replicas during a rolling upgrade and cleaned up by the current leader.
A value of 0 retains none of them — the next cleanup pass removes every entry — so keep the
default (or a larger value) to preserve the legacy async deduplication window during the upgrade.
replicated_deduplication_window_seconds
The number of seconds after which the hash sums of the inserted blocks are removed from ClickHouse Keeper. Possible values:- Any positive integer.
replicated_deduplication_window_seconds specifies how long to store hash
sums of blocks for insert deduplication. Hash sums older than
replicated_deduplication_window_seconds are removed from ClickHouse Keeper,
even if they are less than replicated_deduplication_window.
The time is relative to the time of the most recent record, not to the wall
time. If it’s the only record it will be stored forever.
replicated_deduplication_window_seconds_for_async_inserts
Legacy setting retained for mixed-version rolling upgrades. Together withreplicated_deduplication_window_for_async_inserts it bounds how long legacy async-insert hashes
are kept in the async_blocks directory in ClickHouse Keeper (written by older replicas during a
rolling upgrade and cleaned up by the current leader). New inserts use
replicated_deduplication_window_seconds.