Make a "compressor" an actual class, that can be implemented and
registered via class registry.
For "common" compressors, the objects will be shared, but complex
implementors can be semi-stateful.
sstable compression is split into two parts: The "static" config
which is shared across shards, and a "local" one, which holds
a compressor pointer. The latter is encapsulated, along with
actual compressed data writers, in sstables/compress.cc.
For compression (write), compression writer is instansiated
with the settings active in table metadata.
For decompression (read), compression reader is instansiated
with the settings stored in sstable metadata, which can
differ from the currently active table metadata.
v2:
* Structured patch sets differently (dependencies)
* Added more comments/api descs
* Added patch to move all sstable compression into compress.cc,
effectively separating top-level virtual compressor object
from sstable io knowledge
v3:
* Rebased
v4:
* Moved all sstable compression logic/knowledge into
compress.cc (local compression). Merged the two patches
(separation just confuses reader).
"When moving whole partition entries from memtable to cache, we move
snapshots as well. It is incorrect to evict from such snapshots
though, because associated readers would miss data.
Solution is to record evictability of partition version references (snapshots)
and avoiding eviction from non-evictable snapshots.
Could affect scanning reads, if the reader uses partition entry from
memtable, and the partition is too large to fit in reader's buffer,
and that entry gets moved to cache (was absent in cache), and then
gets evicted (memory pressure). The reader will not see the remainder
of that entry. Found during code review.
Introduced in ca8e3c4, so affects 2.1+
Fixes#3186.
Tests: unit (release)"
* 'tgrabiec/do-not-evict-memtable-snapshots' of github.com:tgrabiec/scylla:
tests: mvcc: Add test for eviction with non-evictable snapshots
mutation_partition: Define + operator on tombstones
tests: mvcc: Check that partition is fully discontinuous after eviction
tests: row_cache: Add test for memtable readers surviving flush and eviction
memtable: Make printable
mvcc: Take partition_entry by const ref in operator<<()
mvcc: Do not evict from non-evictable snapshots
mvcc: Drop unnecessary assignment to partition_snapshot::_version
tests: Use partition_entry::make_evictable() where appropriate
mvcc: Encapsulate construction of evictable entries
Race condition was introduced by commit 028c7a0888, which introduces chunk offset
compression, because a reading state is kept in the compress structure which is
supposed to be immutable and can be shared among shards owning the same sstable.
So it may happen that shard A updates state while shard B relies on information
previously set which leads to incorrect decompression, which in turn leads to
read misbehaving.
We could serialize access to at() which would only lead to contention issues for
shared sstables, but that can be avoided by moving state out of compress structure
which is expected to be immutable after sstable is loaded and feeded to shards that
own it. Sequential accessor (wraps state and reference to segmented_offset) is
added to prevent at() and push_back() interfaces from being polluted.
Tests: release mode.
Fixes#3148.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20180205192432.23405-1-raphaelsc@scylladb.com>
cql_query_test contains many continuations that are generic lambdas:
foo().then([] (auto x) { ... })
These templates prevent Eclipse's indexer from inferring the type of x,
and so everything below that point is one big error as far as Eclipse is
concerned.
De-template these lambdas by specifying the real types.
Unfortunately, compile time decrease was not observed.
Tests: cql_query_test (release)
Message-Id: <20180204113503.23297-1-avi@scylladb.com>
These patches deal with the remaining exception safety issues in the
memtable partition range readers. That includes moving the assignment
to iterator_reader::_last outside of allocating section to avoid
problems caused by exception-unsafe assignment operator. Memory
accotuning code is also moved out of the retryable context to improve
the code robustness and avoid potential problems in the future.
Fixes#3172.
Tests: unit-test (release)
* https://github.com/pdziepak/scylla.git memtable-range-read-exception-safety/v1:
memtable: do not update iterator_reader::_last in alloc section
memtable: do not change accounting state in alloc section
tests/memtable: add more reader exception safety tests
Shared pointer don't like being shared across shards.
Fixes assertion failure in build/debug/tests/mutation_reader_test.
Message-Id: <20180201125017.30259-1-pdziepak@scylladb.com>
"Before this patch set, our Materialized Views implementation can produce
incorrect results when given concurrent updates of the same base-table
row. Such concurrent updates may result, in certain cases, with two
different rows in the view table, instead of just one with the latest
data. In this series we add locking which serializes the two conflicting
updates, and solves this problem.
I explain in more detail why such locking is needed, and what kinds of
locks are needed, in the third patch."
* 'master' of https://github.com/nyh/scylla:
Materialized views: serialize read-modify-update of base table
Materialized views: test row_locker class
Materialized views: implement row and partition locking mechanism
This is a unit test for the row_locker facility. It tests various
combination of shared and exclusive locks on rows and on partitions,
some should succeed immediately and some should block.
This tests the row_locker's API only, it does not use or test anything
in Materialized Views.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Now promoted index is converted into an input_stream and skipped over
instead of being consumed immediately and stored as a single buffer.
The only part that is read right away is the deletion time as it is
likely to be there in the already read buffer and reading it should both
be cheap and prevent from reading the whole promoted index if only
deletion time mark is needed.
When accessed, promoted index is parsed in chunks, buffer by buffer, to
limit memory consumption.
Fixes#2981
Signed-off-by: Vladimir Krivopalov <vladimir@scylladb.com>
It tests mutation_from_streamed_mutation that is no longer
used and will be removed in the next patch.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
It tests freeze(streamed_mutation) which is no longer used
and will be removed in the next patch.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
