The main difficulty was in making sure that emitted range tombstone
changes reflect range tombstones trimmed to clustering restrictions.
This is handled by mutation_fragment_filter and
clustering_ranges_walker. They return a list of range_tombstone_change
fragments to emit for each hop as the reader walks over the clustering
domain.
Tests which were using a normalizing reader expected range tombstones
to be split around rows. Drop this an adjust the tests accoridngly. No
reader splits range tombstones around rows now.
Needed before converting the mx reader to flat_mutation_reader_v2
because now it and the k_l reader cannot share the reader
implementation. They derive from different reader impl bases and push
different fragment types.
The entire sstable cell value is currently stored in a single
temporary_buffer. Cells may be very large, so to avoid large
contiguous allocations, the buffer is changed to
a fragmented_temporary_buffer.
Fixes#7457Fixes#6376
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
Currently, the primitive_consumer parses all values in contiguous buffers.
A string of bytes may be very long, so parsing it in a single buffer
can cause a big allocation. This patch allows parsing into
fragmented_temporary_buffers instead of temporary_buffers.
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
Move stuff contained therein to `sstable_mutation_reader.{hh,cc}` which
will serve as the collection point of utility stuff needed by all reader
implementations.
Move all the mx format specific context and consumer code to
mx/reader.cc and add a factory function `mx::make_reader()` which takes
over the job of instantiating the `sstable_mutation_reader` with the mx
specific context and consumer.
