Currently, if a new sstable is created during repair/streaming,
we invalidate its whole token range in cache. If the sstable
is sparse, we unnecessarily clear too much data.
Modify cache invalidation, so that only the partitions present
in the sstable are cleared.
To check whether a partition is present in the sstable, we use bloom
filters. Bloom filters may return false positives and show that
an sstable contains a partition, even though it does not. Due to that
we may invalidate a bit more than we need to, but the cache will be
in valid state.
An issue arises when we do not invalidate two consecutive partitions
that are continuous. The sstable may contain a token that falls
between these partitions, breaking the continuity. To check that, we
would need to scan sstable index. However, such a change would
noticeably complicate the invalidation, both performance and code.
In this change, sstable index reader isn't used. Instead, the continuity
flag is unset for all scanned partitions. This comes at a cost of
heavier reads, as we will need to verify continuity when reading more
than one partition from cache.
Fixes: https://github.com/scylladb/scylladb/issues/9136.
Closesscylladb/scylladb#25996
The cache should not garbage-collect tombstone which cover data in the
memtable. Add overlap checks (get_max_purgeable) to garbage collection
to detect tombstones which cover data in the memtable and to prevent
their garbage collection.
these unused includes were identified by clang-include-cleaner. after
auditing these source files, all of the reports have been confirmed.
also, took this opportunity to remove an unused namespace alias. and
add an include which is used actually. please note,
`std::ranges::pop_heap()` and friends are actually provided by
`<algorithm>` not `<ranges>`.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#22716
