This pull request adds support for calculation and storing CRC32 digests for all SSTable components.
This change replaces plain file_writer with crc32_digest_file_writer for all SSTable components that should be checksummed. The resulting component digests are stored in the sstable structure
and later persisted to disk as part of the Scylla metadata component during writer::consume_end_of_stream.
Several test cases where introduced to verify expected behaviour.
Additionally, this PR adds new rewrite component mechanism for safe sstable component rewriting.
Previously, rewriting an sstable component (e.g., via rewrite_statistics) created a temporary file that was renamed to the final name after sealing. This allowed crash recovery by simply removing the temporary file on startup.
However, with component digests stored in scylla_metadata (#20100),
replacing a component like Statistics requires atomically updating both the component
and scylla_metadata with the new digest - impossible with POSIX rename.
The new mechanism creates a clone sstable with a fresh generation:
- Hard-links all components from the source except the component being rewritten and scylla_metadata
- Copies original sstable components pointer and recognized components from the source
- Invokes a modifier callback to adjust the new sstable before rewriting
- Writes the modified component along with updated scylla_metadata containing the new digest
- Seals the new sstable with a temporary TOC
- Replaces the old sstable atomically, the same way as it is done in compaction
This is built on the rewrite_sstables compaction framework to support batch operations (e.g., following incremental repair).
In case of any failure durning the whole process, sstable will be automatically deleted on the node startup due to
temporary toc persistence.
Backport is not required, it is a new feature
Fixes https://github.com/scylladb/scylladb/issues/20100, https://github.com/scylladb/scylladb/issues/27453Closesscylladb/scylladb#28338
* github.com:scylladb/scylladb:
docs: document components_digests subcomponent and trailing digest in Scylla.db
sstable_compaction_test: Add tests for perform_component_rewrite
sstable_test: add verification testcases of SSTable components digests persistance
sstables: store digest of all sstable components in scylla metadata
sstables: replace rewrite_statistics with new rewrite component mechanism
sstables: add new rewrite component mechanism for safe sstable component rewriting
compaction: add compaction_group_view method to specify sstable version
sstables: add null_data_sink and serialized_checksum for checksum-only calculation
sstables: extract default write open flags into a constant
sstables: Add write_simple_with_digest for component checksumming
sstables: Extract file writer closing logic into separate methods
sstables: Implement CRC32 digest-only writer
Instead of dht::partition_ranges_vector, which is an std::vector<> and
have been seen to cause large allocations when calculating ranges to be
invalidated after compaction:
seastar_memory - oversized allocation: 147456 bytes. This is non-fatal, but could lead to latency and/or fragmentation issues. Please report: at
[Backtrace #0]
void seastar::backtrace<seastar::current_backtrace_tasklocal()::$_0>(seastar::current_backtrace_tasklocal()::$_0&&, bool) at ./build/release/seastar/./seastar/include/seastar/util/backtrace.hh:89
(inlined by) seastar::current_backtrace_tasklocal() at ./build/release/seastar/./seastar/src/util/backtrace.cc:99
seastar::current_tasktrace() at ./build/release/seastar/./seastar/src/util/backtrace.cc:136
seastar::current_backtrace() at ./build/release/seastar/./seastar/src/util/backtrace.cc:169
seastar::memory::cpu_pages::warn_large_allocation(unsigned long) at ./build/release/seastar/./seastar/src/core/memory.cc:840
seastar::memory::cpu_pages::check_large_allocation(unsigned long) at ./build/release/seastar/./seastar/src/core/memory.cc:903
(inlined by) seastar::memory::cpu_pages::allocate_large(unsigned int, bool) at ./build/release/seastar/./seastar/src/core/memory.cc:910
(inlined by) seastar::memory::allocate_large(unsigned long, bool) at ./build/release/seastar/./seastar/src/core/memory.cc:1533
(inlined by) seastar::memory::allocate_slowpath(unsigned long) at ./build/release/seastar/./seastar/src/core/memory.cc:1679
seastar::memory::allocate(unsigned long) at ././seastar/src/core/memory.cc:1698
(inlined by) operator new(unsigned long) at ././seastar/src/core/memory.cc:2440
(inlined by) std::__new_allocator<interval<dht::ring_position>>::allocate(unsigned long, void const*) at /usr/lib/gcc/x86_64-redhat-linux/15/../../../../include/c++/15/bits/new_allocator.h:151
(inlined by) std::allocator<interval<dht::ring_position>>::allocate(unsigned long) at /usr/lib/gcc/x86_64-redhat-linux/15/../../../../include/c++/15/bits/allocator.h:203
(inlined by) std::allocator_traits<std::allocator<interval<dht::ring_position>>>::allocate(std::allocator<interval<dht::ring_position>>&, unsigned long) at /usr/lib/gcc/x86_64-redhat-linux/15/../../../../include/c++/15/bits/alloc_traits.h:614
(inlined by) std::_Vector_base<interval<dht::ring_position>, std::allocator<interval<dht::ring_position>>>::_M_allocate(unsigned long) at /usr/lib/gcc/x86_64-redhat-linux/15/../../../../include/c++/15/bits/stl_vector.h:387
(inlined by) std::vector<interval<dht::ring_position>, std::allocator<interval<dht::ring_position>>>::reserve(unsigned long) at /usr/lib/gcc/x86_64-redhat-linux/15/../../../../include/c++/15/bits/vector.tcc:79
dht::to_partition_ranges(utils::chunked_vector<interval<dht::token>, 131072ul> const&, seastar::bool_class<utils::can_yield_tag>) at ./dht/i_partitioner.cc:347
compaction::compaction::get_ranges_for_invalidation(std::vector<seastar::lw_shared_ptr<sstables::sstable>, std::allocator<seastar::lw_shared_ptr<sstables::sstable>>> const&) at ./compaction/compaction.cc:619
(inlined by) compaction::compaction::get_compaction_completion_desc(std::vector<seastar::lw_shared_ptr<sstables::sstable>, std::allocator<seastar::lw_shared_ptr<sstables::sstable>>>, std::vector<seastar::lw_shared_ptr<sstables::sstable>, std::allocator<seastar::lw_shared_ptr<sstables::sstable>>>) at ./compaction/compaction.cc:719
(inlined by) compaction::regular_compaction::replace_remaining_exhausted_sstables() at ./compaction/compaction.cc:1362
compaction::compaction::finish(std::chrono::time_point<db_clock, std::chrono::duration<long, std::ratio<1l, 1000l>>>, std::chrono::time_point<db_clock, std::chrono::duration<long, std::ratio<1l, 1000l>>>) at ./compaction/compaction.cc:1021
compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0::operator()() at ./compaction/compaction.cc:1960
(inlined by) compaction::compaction_result std::__invoke_impl<compaction::compaction_result, compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0>(std::__invoke_other, compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0&&) at /usr/lib/gcc/x86_64-redhat-linux/15/../../../../include/c++/15/bits/invoke.h:63
(inlined by) std::__invoke_result<compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0>::type std::__invoke<compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0>(compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0&&) at /usr/lib/gcc/x86_64-redhat-linux/15/../../../../include/c++/15/bits/invoke.h:98
(inlined by) decltype(auto) std::__apply_impl<compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0, std::tuple<>>(compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0&&, std::tuple<>&&, std::integer_sequence<unsigned long, ...>) at /usr/lib/gcc/x86_64-redhat-linux/15/../../../../include/c++/15/tuple:2920
(inlined by) decltype(auto) std::apply<compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0, std::tuple<>>(compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0&&, std::tuple<>&&) at /usr/lib/gcc/x86_64-redhat-linux/15/../../../../include/c++/15/tuple:2935
(inlined by) seastar::future<compaction::compaction_result> seastar::futurize<compaction::compaction_result>::apply<compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0>(compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0&&, std::tuple<>&&) at ././seastar/include/seastar/core/future.hh:1930
(inlined by) seastar::futurize<std::invoke_result<compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0>::type>::type seastar::async<compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0>(seastar::thread_attributes, compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0&&)::'lambda'()::operator()() const at ././seastar/include/seastar/core/thread.hh:267
(inlined by) seastar::noncopyable_function<void ()>::direct_vtable_for<seastar::futurize<std::invoke_result<compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0>::type>::type seastar::async<compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0>(seastar::thread_attributes, compaction::compaction::run(std::unique_ptr<compaction::compaction, std::default_delete<compaction::compaction>>)::$_0&&)::'lambda'()>::call(seastar::noncopyable_function<void ()> const*) at ././seastar/include/seastar/util/noncopyable_function.hh:138
seastar::noncopyable_function<void ()>::operator()() const at ./build/release/seastar/./seastar/include/seastar/util/noncopyable_function.hh:224
(inlined by) seastar::thread_context::main() at ./build/release/seastar/./seastar/src/core/thread.cc:318
dht::partition_ranges_vector is used on the hot path, so just convert
the problematic user -- cache invalidation -- to use
utils::chunked_vector<dht::partition_range> instead.
Fixes: SCYLLADB-121
Closesscylladb/scylladb#28855
Previously, rewriting an sstable component (e.g., via rewrite_statistics) created a temporary file that was renamed
to the final name after sealing. This allows crash recovery by simply removing the temporary file on startup.
However, this approach won't work once component digests are stored in scylla_metadata,
as replacing a component like Statistics will require atomically updating both the component
and scylla_metadata with the new digest—impossible with POSIX rename.
The new mechanism creates a clone sstable with a fresh generation:
- Hard-links all components from the source except the component being rewritten and scylla metadata if update_sstable_id is true
- Copies original sstable components pointer and recognized components from the source
- Invokes a modifier callback to adjust the new sstable before rewriting
- Writes the modified component. If update_sstable_id is true, reads scylla metadata, generates new sstable_id and rewrites it.
- Seals the new sstable with a temporary TOC
- Replaces the old sstable atomically, the same way as it is done in compaction
This is built on the rewrite_sstables compaction framework to support batch operations (e.g., following incremental repair).
In case of any failure during the whole process, sstable will be automatically deleted on the node startup due to
temporary toc persistence.
This prepares the infrastructure for component digests. Once digests are introduced in scylla_metadata
this mechanism will be extended to also rewrite scylla metadata with the updated digest alongside the modified component, ensuring atomic updates of both.
Introduce a new compaction_type enum : `Major`.
This type will be used by the next patches to differentiate between
major compaction and regular compaction (compaction_type::Compaction).
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
This patch adds a new flag `drop-unfixable-sstables` to the scrub operation
in segregate mode, allowing to automatically drop SSTables that
cannot be fixed during scrub. It also includes API support of the 'drop_unfixable_sstables'
paramater and validation to ensure this flag is not enabled in other modes rather than segragate.
This is yet another part in the BTI index project.
Overarching issue: https://github.com/scylladb/scylladb/issues/19191
Previous part: https://github.com/scylladb/scylladb/pull/25626
Next parts: make `ms` the default. Then, general tweaks and improvements. Later, potentially a full `da` format implementation.
This patch series introduces a new, Scylla-only sstable format version `ms`, which is like `me`, but with the index components (Summary.db and Index.db) replaced with BTI index components (Partitions.db and Rows.db), as they are in Cassandra 5.0's `da` format version.
(Eventually we want to just implement `da`, but there are several other changes (unrelated to the index files) between `me` and `da`. By adding this `ms` as an intermediate step we can adapt the new index formats without dragging all the other changes into the mix (and raising the risk of regressions, which is already high)).
The high-level structure of the PR is:
1. Introduce new component types — `Partitions` and `Rows`.
2. Teach `class sstable` to open them when they exist.
3. Teach the sstable writer how to write index data to them.
4. Teach `class sstable` and unit tests how to deal with sstables that have no `Index` or `Summary` (but have `Partitions` and `Rows` instead).
5. Introduce the new sstable version `ms`, specify that it has `Partitions` and `Rows` instead of `Index` and `Summary`.
6. Prepare unit tests for the appearance of `ms`.
7. Enable `ms` in unit tests.
8. Make `ms` enablable via db::config (with a silent fall back to `me` until the new `MS_SSTABLE_FORMAT` cluster feature is enabled).
9. Prepare integration tests for the appearance of `ms`.
10. Enable both `ms` and `me` in tests where we want both versions to be tested.
This series doesn't make `ms` the default yet, because that requires teaching Scylla Manager and a few dtests about the new format first. It can be enabled by setting `sstable_format: ms` in the config.
Per a review request, here is an example from `perf_fast_forward`, demonstrating some motivation for a new format. (Although not the main one. The main motivations are getting rid of restrictions on the RAM:disk ratio, and index read throughput for datasets with tiny partitions). The dataset was populated with `build/release/scylla perf-fast-forward --smp=1 --sstable-format=$VERSION --data-directory=data.$VERSION --column-index-size-in-kb=1 --populate --random-seed=0`.
This test involves a partition with 1000000 clustering rows (with 32-bit keys and 100-byte values) and ~500 index blocks, and queries a few particular rows from the partition. Since the branching factor for the BIG promoted index is 2 (it's a binary search), the lookup involves ~11.2 sequential page reads per row. The BTI format has a more reasonable branching factor, so it involves ~2.3 page reads per row.
`build/release/scylla perf-fast-forward --smp=1 --data-directory=perf_fast_forward_data/me --run-tests=large-partition-select-few-rows`:
```
offset stride rows iterations avg aio aio (KiB)
500000 1 1 70 18.0 18 128
500001 1 1 647 19.0 19 132
0 1000000 1 748 15.0 15 116
0 500000 2 372 29.0 29 284
0 250000 4 227 56.0 56 504
0 125000 8 116 106.0 106 928
0 62500 16 67 195.0 195 1732
```
`build/release/scylla perf-fast-forward --smp=1 --data-directory=perf_fast_forward_data/ms --run-tests=large-partition-select-few-rows`:
```
offset stride rows iterations avg aio aio (KiB)
500000 1 1 51 5.1 5 20
500001 1 1 64 5.3 5 20
0 1000000 1 679 4.0 4 16
0 500000 2 492 8.0 8 88
0 250000 4 804 16.0 16 232
0 125000 8 409 31.0 31 516
0 62500 16 97 54.0 54 1056
```
Index file size comparison for the default `perf_fast_forward` tables with `--random-seed=0`:
Large partition table (dominated by intra-partition index): 2.4 MB with `me`, 732 kB with `ms`.
For the small partitions table (dominated by inter-partition index): 11 MB with `me`, 8.4 MB with `ms`.
External tests:
I ran SCT test `longevity-mv-si-4days-streaming-test` test on 6 nodes with 30 shards each for 8 hours. No anomalies were observed.
New functionality, no backport needed.
Closesscylladb/scylladb#26215
* github.com:scylladb/scylladb:
test/boost/bloom_filter_test: add test_rebuild_from_temporary_hashes
test/cluster: add test_bti_index.py
test: prepare bypass_cache_test.py for `ms` sstables
sstables/trie/bti_index_reader: add a failure injection in advance_lower_and_check_if_present
test/cqlpy/test_sstable_validation.py: prepare the test for `ms` sstables
tools/scylla-sstable: add `--sstable-version=?` to `scylla sstable write`
db/config: expose "ms" format to the users via database config
test: in Python tests, prepare some sstable filename regexes for `ms`
sstables: add `ms` to `all_sstable_versions`
test/boost/sstable_3_x_test: add `ms` sstables to multi-version tests
test/lib/index_reader_assertions: skip some row index checks for BTI indexes
test/boost/sstable_inexact_index_test: explicitly use a `me` sstable
test/boost/sstable_datafile_test: skip test_broken_promoted_index_is_skipped for `ms` sstables
test/resource: add `ms` sample sstable files for relevant tests
test/boost/sstable_compaction_test: prepare for `ms` sstables.
test/boost/index_reader_test: prepare for `ms` sstables
test/boost/bloom_filter_tests: prepare for `ms` sstables
test/boost/sstable_datafile_test: prepare for `ms` sstables
test/boost/sstable_test: prepare for `ms` sstables.
sstables: introduce `ms` sstable format version
tools/scylla-sstable: default to "preferred" sstable version, not "highest"
sstables/mx/reader: use the same hashed_key for the bloom filter and the index reader
sstables/trie/bti_index_reader: allow the caller to passing a precalculated murmur hash
sstables/trie/bti_partition_index_writer: in add(), get the key hash from the caller
sstables/mx: make Index and Summary components optional
sstables: open Partitions.db early when it's needed to populate key range for sharding metadata
sstables: adapt sstable::set_first_and_last_keys to sstables without Summary
sstables: implement an alternative way to rebuild bloom filters for sstables without Index
utils/bloom_filter: add `add(const hashed_key&)`
sstables: adapt estimated_keys_for_range to sstables without Summary
sstables: make `sstable::estimated_keys_for_range` asynchronous
sstables/sstable: compute get_estimated_key_count() from Statistics instead of Summary
replica/database: add table::estimated_partitions_in_range()
sstables/mx: implement sstable::has_partition_key using a regular read
sstables: use BTI index for queries, when present and enabled
sstables/mx/writer: populate BTI index files
sstables: create and open BTI index files, when enabled
sstables: introduce Partition and Rows component types
sstables/mx/writer: make `_pi_write_m.partition_tombstone` a `sstables::deletion_time`
Currently, `sstable::estimated_keys_for_range` works by
checking what fraction of Summary is covered by the given
range, and multiplying this fraction to the number of all keys.
Since computing things on Summary doesn't involve I/O (because Summary
is always kept in RAM), this is synchronous.
In a later patch, we will modify `sstable::estimated_keys_for_range`
so that it can deal with sstables that don't have a Summary
(because they use BTI indexes instead of BIG indexes).
In that case, the function is going to compute the relevant fraction
by using the index instead of Summary. This will require making
the function asynchronous. This is what we do in this patch.
(The actual change to the logic of `sstable::estimated_keys_for_range`
will come in the next patch. In this one, we only make it asynchronous).
sstables/exceptions.hh still hosts some compaction specific exception
types. Move them over to the new compaction/exceptions.hh, to make the
compaction module more self-contained.
The namespace usage in this directory is very inconsistent, with files
and classes scattered in:
* global namespace
* namespace compaction
* namespace sstables
With cases, where all three used in the same file. This code used to
live in sstables/ and some of it still retains namespace sstables as a
heritage of that time. The mismatch between the dir (future module) and
the namespace used is confusing, so finish the migration and move all
code in compaction/ to namespace compaction too.
This patch, although large, is mechanic and only the following kind of
changes are made:
* replace namespace sstable {} with namespace compaction {}
* add namespace compaction {}
* drop/add sstables::
* drop/add compaction::
* move around forward-declarations so they are in the correct namespace
context
This refactoring revealed some awkward leftover coupling between
sstables and compaction, in sstables/sstable_set.cc, where the
make_sstable_set() methods of compaction strategies are implemented.
This PR improves the handling of malformed SSTables during scrub and adds tests to validate the updated behavior.
When scrub is used, there is an increased chance of encountering malformed SSTables. These should not be retried as in regular compaction. Instead, they must be handled according to the selected scrub mode: in skip mode, in case of malformed_sstable_exception, invalid data or whole SSTable should be removed, in abort and segregate modes, the scrub process should abort.
Previously, all modes treated malformed_sstable_exception the same way, causing scrub to abort even when skip mode was selected. This PR updates the scrub logic to properly handle malformed SSTable exceptions based on the selected mode.
Unit tests are added to verify the intended behavior.
Fixesscylladb/scylladb#19059
Backport is not required, it is an improvement
Closesscylladb/scylladb#25828
* github.com:scylladb/scylladb:
sstable_compaction_test: add scrub tests for malformed SSTables
scrub: skip sstable on malformed sstable exception in skip mode
As requested in #22104, moved the files and fixed other includes and build system.
Moved files:
- combine.hh
- collection_mutation.hh
- collection_mutation.cc
- converting_mutation_partition_applier.hh
- converting_mutation_partition_applier.cc
- counters.hh
- counters.cc
- timestamp.hh
Fixes: #22104
This is a cleanup, no need to backport
Closesscylladb/scylladb#25085
Previously, malformed_sstable_exception during scrub was handled the same way in
abort, skip and segragate mode, causing the scrub process to abort even when skip was specified.
This commit updates the behavior to correctly handle malformed_sstable_exception in
skip mode by removing invalid data or whole malformed SSTable instead of aborting the entire scrub.
In validate mode, scrub moves invalid sstables into the quarantine
folder. If validation fails because the sstable files are missing from
disk, there is nothing to move, and the quarantine step will throw an
exception. Handle such exceptions so scrub can return a proper
compaction_result instead of propagating the exception to the caller.
This will help the testcase for #23363 to reliably determine if the
scrub has failed or not.
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
Currently, in compaction::setup compaction_size is updated in a loop.
Due to that the total progress of compaction executors grows during
their execution.
Add the sstables sizes to a compaction_size variable. Update
compaction_data::compaction_size after the loop.
The central idea of incremental repair is to allow repair participants
to select and repair only a portion of the dataset to speed up the
repair process. All repair participants must utilize an identical
selection method to repair and synchronize the same selected dataset.
There are two primary selection methods: time-based and file-based. The
time-based method selects data within a specified time frame. It is
versatile but it is less efficient because it requires reading all of
the dataset and omitting data beyond the time frame. The file-based
method selects data from unrepaired SSTables and is more efficient
because it allows the entire SSTable to be omitted. This document patch
implements the file-based selection method.
Incremental repair will only be supported for tablet tables; it will not
be supported for vnode tables. On one hand, the legacy vnode is less
important to support. On the other hand, the incremental repair for
vnode is much harder to implement. With vnodes, a SSTalbe could contain
data for multiple vnode ranges. When a given vnode range is repaired,
only a portion of the SSTable is repaired. This complicates the
manipulation of SSTables significantly during both repair and
compaction. With tablets, an entire tablet is repaired so that a
sstable is either fully repaired or not repaired which is a huge
simplification.
This patch uses the repaired_at from sstables::statistics component to
mark a sstable as repaired. It uses a virtual clock as the repair
timestamp, i.e., using a monotonically increasing number for the
repaired_at field of a SSTable and sstables_repaired_at column in
system.tablets table. Notice that when a sstable is not repaired, the
repaired_at field will be set to the default value 0 by default. The
being_repaired in memory field of a SSTable is used to explicitly mark
that a SSTable is being selected. The following variables are used for
incremental repair:
The repaired_at on disk field of a SSTable is used.
- A 64-bit number increases sequentially
The sstables_repaired_at is added to the system.tablets table.
- repaired_at <= sstables_repaired_at means the sstable is repaired
The being_repaired in memory field of a SSTable is added.
- A repair UUID tells which sstable has participated in the repair
Initial test results:
1) Medium dataset results
Node amount: 3
Instance type: i4i.2xlarge
Disk usage per node: ~500GB
Cluster pre-populated with ~500GB of data before starting repairs job.
Results for Repair Timings:
The regular repair run took 210 mins.
Incremental repair 1st run took 183 mins, 2nd and 3rd runs took around 48s
The speedup is: 183 mins / 48s = 228X
2) Small dataset results
Node amount: 3
Instance type: i4i.2xlarge
Disk usage per node: ~167GB
Cluster pre-populated with ~167GB of data before starting the repairs job.
Regular repair 1st run took 110s, 2nd and 3rd runs took 110s.
Incremental repair 1st run took 110 seconds, 2nd and 3rd run took 1.5 seconds.
The speedup is: 110s / 1.5s = 73X
3) Large dataset results
Node amount: 6
Instance type: i4i.2xlarge, 3 racks
50% of base load, 50% read/write
Dataset == Sum of data on each node
Dataset Non-incremental repair (minutes)
1.3 TiB 31:07
3.5 TiB 25:10
5.0 TiB 19:03
6.3 TiB 31:42
Dataset Incremental repair (minutes)
1.3 TiB 24:32
3.0 TiB 13:06
4.0 TiB 5:23
4.8 TiB 7:14
5.6 TiB 3:58
6.3 TiB 7:33
7.0 TiB 6:55
Fixes#22472Closesscylladb/scylladb#24291
* github.com:scylladb/scylladb:
replica: Introduce get_compaction_reenablers_and_lock_holders_for_repair
compaction: Move compaction_reenabler to compaction_reenabler.hh
topology_coordinator: Make rpc::remote_verb_error to warning level
repair: Add metrics for sstable bytes read and skipped from sstables
test.py: Disable incremental for test_tombstone_gc_for_streaming_and_repair
test.py: Add tests for tablet incremental repair
repair: Add tablet incremental repair support
compaction: Add tablet incremental repair support
feature_service: Add TABLET_INCREMENTAL_REPAIR feature
tablet_allocator: Add tablet_force_tablet_count_increase and decrease
repair: Add incremental helpers
sstable: Add being_repaired to sstable
sstables: Add set_repaired_at to metadata_collector
mutation_compactor: Introduce add operator to compaction_stats
tablet: Add sstables_repaired_at to system.tablets table
test: Fix drain api in task_manager_client.py
This patch addes incremental_repair support in compaction.
- The sstables are split into repaired and unrepaired set.
- Repaired and unrepaired set compact sperately.
- The repaired_at from sstable and sstables_repaired_at from
system.tablets table are used to decide if a sstable is repaired or
not.
- Different compactions tasks, e.g., minor, major, scrub, split, are
serialized with tablet repair.
Allow possibly avoiding overlap checks in the case where the source of
the min-live timestamp is known to only contain data which was written
*after* expiry treshold. Expiry treshold is the upper bound of
tombstone.deletion_time that was already expired at the time of
obtaining this expiry treshold value. Meaning that any write originating
from after this point in time, was generated at a time when such
tombstone was already expired. Hence these writes are not relevant for
the purposes of overlap checks with the tombstone and so their min-live
timestamp can be ignored.
This is important for MV workloads, where writes generated now can have
timestamps going far back in time, possibly blocking tombstone GC of
much older [shadowable] tombstones.
We are used to symbols definition being grouped in one .cc file, but a
symbol declaration and definition living in separate modules
(subfolders) is surprising.
Relocate always_gc, never_gc, can_always_purge and can_never_purge to
compaction/compaction.cc, from mutatiobn/mutation_partition.cc. The
declarations of these symbols is in
compaction/compaction_garbage_collector.hh.
Since table_state is a view to a compaction group, it makes sense
to rename it as so.
With upcoming incremental repair, each replica::compaction_group
will be actually two compaction groups, so there will be two
views for each replica::compaction_group.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Compaction is routine and the log messages pollute the log files,
hiding important information.
All the data is available via `nodetool compactionhistory`.
Reduce noise by demoting those log messages to debug level.
One test is adjusted to use debug level for compaction, since it
listens for those messages.
Closesscylladb/scylladb#24949
Print the keyspace.table names, issue trace log messages also
when returning early if tombstone_gc is disabled or
when gc_check_only_compacting_sstables is set.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Closesscylladb/scylladb#24914
Collect tombstone purge statistics like
+ total number of purge attempts
+ number of purge failures due to data overlapping with memtables
+ number of purge failures due to data overlapping with non-compacting
sstables
and expose them in the compaction_stats structure.
Currently, when a max purgeable timestamp is computed, there is no
information where it comes from and how the value was obtained.
Take compaction, if there are memtables or other uncompacting sstables
possibly shadowing data, the timestamp is decreased to ensure a
tombstone is not purged but the caller does not know what that the
timestamp has its value.
In this patch, we extend the return type of max_purgeable_fn to
contain not only a timestamp but also an information on how it was
computed. This information will be required to collect statistics
on tombstone purge failures due to overlapping memtables/uncompacting
sstables that come later in the series.
The compaction_result struct has been extended with the following
properties:
+ id of the shard the compaction took place on
+ type of the compaction
+ time when the compaction started
+ list of sstable files to be compacted
+ list of sstable files generated by compaction
Interval map is very susceptible to quadratic space behavior when
it's flooded with many entries overlapping all (or most of)
intervals, since each such entry will have presence on all
intervals it overlaps with.
A trigger we observed was memtable flush storm, which creates many
small "L0" sstables that spans roughly the entire token range.
Since we cannot rely on insertion order, solution will be about
storing sstables with such wide ranges in a vector (unleveled).
There should be no consequence for single-key reads, since upper
layer applies an additional filtering based on token of key being
queried.
And for range scans, there can be an increase in memory usage,
but not significant because the sstables span an wide range and
would have been selected in the combined reader if the range of
scan overlaps with them.
Anyway, this is a protection against storm of memtable flushes
and shouldn't be the common scenario.
It works both with tablets and vnodes, by adjusting the token
range spanned by compaction group accordingly.
Fixes#23634.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
now that we are allowed to use C++23. we now have the luxury of using
`std::ranges::to`.
in this change, we:
- replace `boost::copy_range` to `std::ranges::to`
- remove unused `#include` of boost headers
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#21880
now that we are allowed to use C++23. we now have the luxury of using
`std::views::transform`.
in this change, we:
- replace `boost::adaptors::transformed` with `std::views::transform`
- use `fmt::join()` when appropriate where `boost::algorithm::join()`
is not applicable to a range view returned by `std::view::transform`.
- use `std::ranges::fold_left()` to accumulate the range returned by
`std::view::transform`
- use `std::ranges::fold_left()` to get the maximum element in the
range returned by `std::view::transform`
- use `std::ranges::min()` to get the minimal element in the range
returned by `std::view::transform`
- use `std::ranges::equal()` to compare the range views returned
by `std::view::transform`
- remove unused `#include <boost/range/adaptor/transformed.hpp>`
- use `std::ranges::subrange()` instead of `boost::make_iterator_range()`,
to feed `std::views::transform()` a view range.
to reduce the dependency to boost for better maintainability, and
leverage standard library features for better long-term support.
this change is part of our ongoing effort to modernize our codebase
and reduce external dependencies where possible.
limitations:
there are still a couple places where we are still using
`boost::adaptors::transformed` due to the lack of a C++23 alternative
for `boost::join()` and `boost::adaptors::uniqued`.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#21700
these unused includes are identified by clang-include-cleaner. after
auditing the source files, all of the reports have been confirmed.
please note, because `mutation/mutation.hh` does not include
`seastar/coroutine/maybe_yield.hh` anymore, and quite a few source
files were relying on this header to bring in the declaration of
`maybe_yield()`, we have to include this header in the places where
this symbol is used. the same applies to `seastar/core/when_all.hh`.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
This PR enables compaction tasks to verify the integrity of the input data through checksum and digest checks. The mechanism for integrity checking was introduced in previous PRs (#20207, #20720) as a built-in functionality of the input streams. This PR integrates this mechanism with compaction. The change applies to all compaction types and covers both compressed and uncompressed SSTables adhering to the 3.x format. If a compaction task reads only part of an SSTable, then only the per-chunk checksums are verified, not the digest.
The PR consists of:
* Changes to mx readers to support integrity checking. The kl readers, considered as compatibility-only, were left unchanged. Also, integrity checking on single-partition reversed reads (`data_consume_reversed_partition()`) remains unsupported by mx readers as this is not used in compaction.
* Changes to `sstable` and `sstable_set` APIs to allow toggling integrity checks for mx readers.
* Activation of integrity checking for all compaction types.
* Tests for all compaction types with corrupted SSTables.
Integrity checks come at a cost. For uncompressed SSTables, the cost is the loading of the CRC and Digest components from disk, and the calculation of checksums and digest from the actual data. For compressed SSTables, checksums are stored in-place and they are being checked already on all reads, so the only extra cost is the loading and calculation of the digest. The measurements show a ~5% regression in compaction performance for uncompressed SSTables, and a negligible regression for compressed SSTables.
Command: `perf-sstable --smp=1 --cpuset=1 --poll-mode --mode=compaction --iterations=1000 --partitions 10000 --sstables=1 --key_size=4096 --num_columns=15 --column_size={32, 1024, 3500, 7000, 14500}`
Uncompressed SSTables:
```
+--------------+-----------------------+----------------------+------------+
| SSTable Size | No Integrity (p/sec) | Integrity (p/sec) | Regression |
+--------------+-----------------------+----------------------+------------+
| 50 MiB | 65175.59 +- 80.82 | 61814.63 +- 72.88 | 5.16% |
| 200 MiB | 41795.10 +- 60.39 | 39686.28 +- 45.05 | 5.05% |
| 500 MiB | 21087.41 +- 30.72 | 20092.93 +- 25.05 | 4.72% |
| 1 GiB | 12781.64 +- 21.77 | 12233.94 +- 21.71 | 4.29% |
| 2 GiB | 6629.99 +- 9.40 | 6377.13 +- 8.28 | 3.81% |
+--------------+-----------------------+----------------------+------------+
```
Compressed SSTables:
```
+--------------+-----------------------+----------------------+------------+
| SSTable Size | No Integrity (p/sec) | Integrity (p/sec) | Regression |
+--------------+-----------------------+----------------------+------------+
| 50 MiB | 53975.05 +- 63.18 | 53825.93 +- 62.28 | 0.28% |
| 200 MiB | 28687.94 +- 26.58 | 28689.41 +- 26.91 | 0% |
| 500 MiB | 13865.35 +- 15.50 | 13790.41 +- 14.88 | 0.54% |
| 1 GiB | 7858.10 +- 7.71 | 7829.75 +- 9.66 | 0.36% |
| 2 GiB | 4023.11 +- 2.43 | 4010.54 +- 2.55 | 0.31% |
+--------------+-----------------------+----------------------+------------+
(p/sec = partitions/sec)
```
Refs #19071.
New feature, no backport is needed.
Closesscylladb/scylladb#21153
* github.com:scylladb/scylladb:
test: Add test for compaction with corrupted SSTables
compaction: Enable integrity checks for all compaction types
sstables: Add integrity option to factories for sstable_set readers
sstables: Add integrity option to sstable::make_reader()
sstables: Add integrity option to mx::make_reader()
sstables: Load checksums and digests in mx full-scan reader
sstables: Add integrity option to data_consume_single_partition()
sstables: Disengage integrity_check from sstable class
sstables: Allow data sources to disable digest check
Compaction tasks create mutation readers to read SSTables from disk.
Each compaction type defines its own reader creation logic by
implementing the pure virtual function `compaction::make_sstable_reader()`.
Modify all implementations of `make_sstable_reader()` to enable
integrity checking on the created readers. This way, all compaction
tasks will be able to detect corruption issues on the compacting
SSTables.
Signed-off-by: Nikos Dragazis <nikolaos.dragazis@scylladb.com>
Split compaction divides the partitions in an existing sstable into two
groups and writes them into two new sstables, which replace the original
one. The partition count from the original sstable is used as an
estimate when writing the new ones, but this estimate is not accurate as
the partitions are split between the two new sstables and each will
contain only a portion of the original partition count. This also causes
the bloom filters to be rebuilt at the end of compaction, as they were
initially built with inaccurate estimates.
Fix this by using a better estimate for the output sstables based on the
token ranges written to them.
Fixes scylladb#20253
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
now that we are allowed to use C++23. we now have the luxury of using
`std::ranges::any_of`.
in this change, we replace `boost::algorithm::any_of` with
`std::ranges::any_of`
to reduce the dependency to boost for better maintainability, and
leverage standard library features for better long-term support.
this change is part of our ongoing effort to modernize our codebase
and reduce external dependencies where possible.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
now that we are allowed to use C++23. we now have the luxury of using
`std::views::values`.
in this change, we:
- replace `boost::adaptors::map_values` with `std::views::values`
- update affected code to work with `std::views::values`
- the places where we use `boost::join()` are not changed, because
we cannot use `std::views::concat` yet. this helper is only
available in C++26.
to reduce the dependency to boost for better maintainability, and
leverage standard library features for better long-term support.
this change is part of our ongoing effort to modernize our codebase
and reduce external dependencies where possible.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#21265
A new field has been added to the compaction_stats structure to hold
collected combined reader statistics. The struct is than used to update
the compaction_history table.
Compaction classes start mutate their internal members to be used
in methods setup_sstable_reader and make_sstable_reader creating
sstable reades that are marked as const.
Remove the const qualifier from these methods. Even though it made
sense initially to mark them as const, it is no longer applicable.
This includes way too much, including <boost/regex.hpp>, which is huge.
Drop includes of adaptors.hpp and replace by what is needed.
Closesscylladb/scylladb#21187
During split prepare phase, there will be more than 1 compaction group with
overlapping token range for a given replica.
Assume tablet 1 has sstable A containing deleted data, and sstable B containing
a tombstone that shadows data in A.
Then split starts:
1) sstable B is split first, and moved from main (unsplit) group to a
split-ready group
2) now compaction runs in split-ready group before sstable A is split
tombstone GC logic today only looks at underlying group, so compaction is step
2 will discard the deleted data in A, since it belongs to another group (the
unsplit one), and so the tombstone can be purged incorrectly.
To fix it, compaction will now work with all uncompacting sstables that belong
to the same replica, since tombstone GC requires all sstables that possibly
contain shadowed data to be available for correct decision to be made.
Fixes https://github.com/scylladb/scylladb/issues/20044.
Branches 6.0, 6.1 and 6.2 are vulnerable, so backport is needed.
Closesscylladb/scylladb#20939
* github.com:scylladb/scylladb:
replica: Fix tombstone GC during tablet split preparation
service: Improve error handling for split
when building scylla with the standard library from GCC-14.2, shipped by
fedora 41, we have following build failure:
```
/home/kefu/.local/bin/clang++ -DDEBUG -DDEBUG_LSA_SANITIZER -DFMT_SHARED -DSANITIZE -DSCYLLA_BUILD_MODE=debug -DSCYLLA_ENABLE_ERROR_INJECTION -DSEASTAR_API_LEVEL=7 -DSEASTAR_DEBUG -DSEASTAR_DEBUG_PROMISE -DSEASTAR_DEBUG_SHARED_PTR -DSEASTAR_DEFAULT_ALLOCATOR -DSEASTAR_LOGGER_COMPILE_TIME_FMT -DSEASTAR_LOGGER_TYPE_STDOUT -DSEASTAR_SCHEDULING_GROUPS_COUNT=16 -DSEASTAR_SHUFFLE_TASK_QUEUE -DSEASTAR_SSTRING -DSEASTAR_TYPE_ERASE_MORE -DXXH_PRIVATE_API -DCMAKE_INTDIR=\"Debug\" -I/home/kefu/dev/scylladb -I/home/kefu/dev/scylladb/build/gen -I/home/kefu/dev/scylladb/seastar/include -I/home/kefu/dev/scylladb/build/seastar/gen/include -I/home/kefu/dev/scylladb/build/seastar/gen/src -isystem /home/kefu/dev/scylladb/abseil -g -Og -g -gz -std=gnu++23 -fvisibility=hidden -Wall -Werror -Wextra -Wno-error=deprecated-declarations -Wimplicit-fallthrough -Wno-c++11-narrowing -Wno-deprecated-copy -Wno-mismatched-tags -Wno-missing-field-initializers -Wno-overloaded-virtual -Wno-unsupported-friend -Wno-unused-parameter -ffile-prefix-map=/home/kefu/dev/scylladb/build=. -march=x86-64-v3 -mpclmul -Xclang -fexperimental-assignment-tracking=disabled -Werror=unused-result -fstack-clash-protection -fsanitize=address -fsanitize=undefined -MD -MT CMakeFiles/scylla-main.dir/Debug/init.cc.o -MF CMakeFiles/scylla-main.dir/Debug/init.cc.o.d -o CMakeFiles/scylla-main.dir/Debug/init.cc.o -c /home/kefu/dev/scylladb/init.cc
In file included from /home/kefu/dev/scylladb/init.cc:12:
In file included from /home/kefu/dev/scylladb/db/config.hh:20:
In file included from /home/kefu/dev/scylladb/locator/abstract_replication_strategy.hh:26:
/home/kefu/dev/scylladb/locator/tablets.hh:410:30: error: unexpected type name 'size_t': expected expression
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ^
/home/kefu/dev/scylladb/locator/tablets.hh:410:23: error: no member named 'irange' in namespace 'boost'
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ~~~~~~~^
/home/kefu/dev/scylladb/locator/tablets.hh:410:38: error: left operand of comma operator has no effect [-Werror,-Wunused-value]
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ^
3 errors generated.
[16/782] Building CXX object CMakeFiles/scylla-main.dir/Debug/keys.cc.o
[17/782] Building CXX object CMakeFiles/scylla-main.dir/Debug/counters.cc.o
[18/782] Building CXX object CMakeFiles/scylla-main.dir/Debug/partition_slice_builder.cc.o
[19/782] Building CXX object CMakeFiles/scylla-main.dir/Debug/mutation_query.cc.o
FAILED: CMakeFiles/scylla-main.dir/Debug/mutation_query.cc.o
/home/kefu/.local/bin/clang++ -DDEBUG -DDEBUG_LSA_SANITIZER -DFMT_SHARED -DSANITIZE -DSCYLLA_BUILD_MODE=debug -DSCYLLA_ENABLE_ERROR_INJECTION -DSEASTAR_API_LEVEL=7 -DSEASTAR_DEBUG -DSEASTAR_DEBUG_PROMISE -DSEASTAR_DEBUG_SHARED_PTR -DSEASTAR_DEFAULT_ALLOCATOR -DSEASTAR_LOGGER_COMPILE_TIME_FMT -DSEASTAR_LOGGER_TYPE_STDOUT -DSEASTAR_SCHEDULING_GROUPS_COUNT=16 -DSEASTAR_SHUFFLE_TASK_QUEUE -DSEASTAR_SSTRING -DSEASTAR_TYPE_ERASE_MORE -DXXH_PRIVATE_API -DCMAKE_INTDIR=\"Debug\" -I/home/kefu/dev/scylladb -I/home/kefu/dev/scylladb/build/gen -I/home/kefu/dev/scylladb/seastar/include -I/home/kefu/dev/scylladb/build/seastar/gen/include -I/home/kefu/dev/scylladb/build/seastar/gen/src -isystem /home/kefu/dev/scylladb/abseil -g -Og -g -gz -std=gnu++23 -fvisibility=hidden -Wall -Werror -Wextra -Wno-error=deprecated-declarations -Wimplicit-fallthrough -Wno-c++11-narrowing -Wno-deprecated-copy -Wno-mismatched-tags -Wno-missing-field-initializers -Wno-overloaded-virtual -Wno-unsupported-friend -Wno-unused-parameter -ffile-prefix-map=/home/kefu/dev/scylladb/build=. -march=x86-64-v3 -mpclmul -Xclang -fexperimental-assignment-tracking=disabled -Werror=unused-result -fstack-clash-protection -fsanitize=address -fsanitize=undefined -MD -MT CMakeFiles/scylla-main.dir/Debug/mutation_query.cc.o -MF CMakeFiles/scylla-main.dir/Debug/mutation_query.cc.o.d -o CMakeFiles/scylla-main.dir/Debug/mutation_query.cc.o -c /home/kefu/dev/scylladb/mutation_query.cc
In file included from /home/kefu/dev/scylladb/mutation_query.cc:12:
In file included from /home/kefu/dev/scylladb/schema/schema_registry.hh:17:
In file included from /home/kefu/dev/scylladb/replica/database.hh:11:
In file included from /home/kefu/dev/scylladb/locator/abstract_replication_strategy.hh:26:
/home/kefu/dev/scylladb/locator/tablets.hh:410:30: error: unexpected type name 'size_t': expected expression
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ^
/home/kefu/dev/scylladb/locator/tablets.hh:410:23: error: no member named 'irange' in namespace 'boost'
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ~~~~~~~^
/home/kefu/dev/scylladb/locator/tablets.hh:410:38: error: left operand of comma operator has no effect [-Werror,-Wunused-value]
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ^
In file included from /home/kefu/dev/scylladb/mutation_query.cc:12:
In file included from /home/kefu/dev/scylladb/schema/schema_registry.hh:17:
In file included from /home/kefu/dev/scylladb/replica/database.hh:37:
In file included from /home/kefu/dev/scylladb/db/snapshot-ctl.hh:20:
/home/kefu/dev/scylladb/tasks/task_manager.hh:403:54: error: no member named 'irange' in namespace 'boost'
403 | co_await coroutine::parallel_for_each(boost::irange(0u, smp::count), [&tm, id, &res, &func] (unsigned shard) -> future<> {
| ~~~~~~~^
4 errors generated.
```
so let's take the opportunity to switch from `boost::irange` to
`std::views::iota`.
in this change, we:
- switch from boost::irange to std::views::iota for better standard library compatibility
- retain boost::irange where step parameter is used, as std::views::iota doesn't support it
- this change partially modernizes our range usage while maintaining
- existing functionality
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#20924
During split prepare phase, there will be more than 1 compaction group with
overlapping token range for a given replica.
Assume tablet 1 has sstable A containing deleted data, and sstable B containing
a tombstone that shadows data in A.
Then split starts:
1) sstable B is split first, and moved from main (unsplit) group to a
split-ready group
2) now compaction runs in split-ready group before sstable A is split
tombstone GC logic today only looks at underlying group, so compaction is step
2 will discard the deleted data in A, since it belongs to another group (the
unsplit one), and so the tombstone can be purged incorrectly.
To fix it, compaction will now work with all uncompacting sstables that belong
to the same replica, since tombstone GC requires all sstables that possibly
contain shadowed data to be available for correct decision to be made.
Fixes#20044.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
