Commit Graph

3802 Commits

Author SHA1 Message Date
Pavel Emelyanov
10376b5b85 db: Re-use database::snapshot_table_on_all_shards()
There are two snapshot-on-all-shards methods on the database -- the one
that snapshots a keyspace and the one that snapshots a vector of tables.
The latter snapshots a single table with a neat helper, while the former
has the helper open-coded.

Re-using the helper in keyspace snapshot is worth it, but needs to patch
the helper to work on uuid, rather than ks:cf pair of strings.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>

Closes scylladb/scylladb#23532
2025-04-07 11:55:43 +02:00
Botond Dénes
1198213000 Merge 'tablets: Make tablet allocation equalize per-shard load ' from Tomasz Grabiec
Before, it was equalizing per-node load (tablet count), which is wrong
in heterogeneous clusters. Nodes with fewer shards will end up with
overloaded shards.

Refs #23378

Closes scylladb/scylladb#23478

* github.com:scylladb/scylladb:
  tablets: Make tablet allocation equalize per-shard load
  tablets: load_balancer: Fix reporting of total load per node
2025-04-03 16:32:53 +03:00
Botond Dénes
fcdae20fd1 Merge 'Add tablet enforcing option' from Benny Halevy
This series add a new config option: `tablets_mode_for_new_keyspaces` that replaces the existing
`enable_tablets` option. It can be set to the following values:
    disabled: New keyspaces use vnodes by default, unless enabled by the tablets={'enabled':true} option
    enabled:  New keyspaces use tablets by default, unless disabled by the tablets={'disabled':true} option
    enforced: New keyspaces must use tablets. Tablets cannot be disabled using the CREATE KEYSPACE option

`tablets_mode_for_new_keyspaces=disabled` or `tablets_mode_for_new_keyspaces=enabled` control whether
tablets are disabled or enabled by default for new keyspaces, respectively.
In either cases, tablets can be opted-in or out using the `tablets={'enabled':...}`
keyspace option, when the keyspace is created.

`tablets_mode_for_new_keyspaces=enforced` enables tablets by default for new keyspaces,
like `tablets_mode_for_new_keyspaces=enabled`.
However, it does not allow to opt-out when creating
new keyspaces by setting `tablets = {'enabled': false}`

Refs scylladb/scylla-enterprise#4355

* Requires backport to 2025.1

Closes scylladb/scylladb#22273

* github.com:scylladb/scylladb:
  boost/tablets_test: verify failure to create keyspace with tablets and non network replication strategy
  tablets: enforce tablets using tablets_mode_for_new_keyspaces=enforced config option
  db/config: add tablets_mode_for_new_keyspaces option
2025-04-03 16:32:19 +03:00
Botond Dénes
a0d8102a1f replica/memtable: s/make_flat_reader/make_mutation_reader/
Following the recent refactoring of removing "flat" and "v2" from reader
names, replacing all the fully qualified names with simply "mutation_reader".

Closes scylladb/scylladb#23346
2025-04-01 17:58:13 +03:00
Pavel Emelyanov
2ee9cec1d3 Merge 'Remove object_storage.yaml and move the endpoints to scylla.yaml' from Robert Bindar
Move `object_storage.yaml` endpoints to `scylla.yaml`

This change also removes the `object_storage.yaml` file
altogether and adds tests for fetching the endpoints
via the `v2/config/object_storage_endpoints` REST api.

Also, `object_storage_config_file` options is moved to a deprecated state as it's no longer needed.

This PR depends on #22951, the reviewers should review patch 393e1ac0ec066475ca94094265a5f88dbbdb1a1f

Refs https://github.com/scylladb/scylladb/issues/22428

Closes scylladb/scylladb#22952

* github.com:scylladb/scylladb:
  Remove db::config::object_storage_config
  Move `object_storage.yaml` endpoints to `scylla.yaml`
2025-04-01 16:01:44 +03:00
Avi Kivity
69684e16d8 Merge 'sstables: add SSTable compression with shared dictionaries ' from Michał Chojnowski
This PR extends Scylla's SSTable compression with the ability to use compression dictionaries shared across compression chunks. This involves several changes:

- We refactor `compression_parameters` and friends (`compressor`, `sstables::local_compression`, `sstables::compression`) to prepare for making the construction of `compressor`s asynchronous, to enable sharing pieces of compressors (the dictionaries) across shards.
- We introduce the notion of "hidden compression options" which are written to `CompressionInfo.db` and used to construct decompressors, like regular options, but don't appear in the schema. (We later stuff the SSTable's dictionary into `CompressionInfo.db` using a sequence of such options).
- We add a cluster feature which guards the creation of dictionary-compressed SSTables.
- We introduce a central "compressor factory" (one instance shared by all shards), which from this point onward is used to construct all `compressor` objects (one per SSTable) used to process the SSTables. When constructing a compressor for writing, it uses the "current"/"recommended" dictionary (which is passed to the factory from the actively-observed contents of the group0-managed `system.dicts`). When constructing a compressor for reading, it uses the dictionary written in the hidden compression options in CompressionInfo.db. And it keeps dictionaries deduplicated, so that each unique live dictionary blob has only one instance in memory, shared across shards.
- We teach the relevant `lz4` and `zstd` compressor wrappers about the dictionaries.
- We add a HTTP API call which samples pieces of the given table (i.e. the Data.db files) from across the cluster, trains a dictionary on it, and publishes it via `system.dicts` as the new current dictionary for that table. (And we add some RPC verbs to support that).
- We add a HTTP API call which estimates the impact of various available compression configurations on the compression ratio.
- We add an autotrainer fiber which periodically retrains dicts for dict-aware tables and publishes them if they seem to be a significant improvement.

Known imperfections:
- The factory currently keeps one dictionary instance on the entire node, but we probably want one copy per NUMA node. I didn't do that because exposing NUMA knowledge to Scylla seems to require some changes in Seastar first.

New feature, no backporting involved.

Closes scylladb/scylladb#23025

* github.com:scylladb/scylladb:
  docs: add user-facing documentation for SSTable compression with shared dicts
  docs/dev: add sstable-compression-dicts.md
  test: add test_sstable_compression_dictionaries_autotrain.py
  test: add test_sstable_compression_dictionaries_basic.py
  test/pylib/rest_client: add `keyspace_upgrade_sstables` helper
  main: run a sstable_dict_autotrainer
  api: add the estimate_compression_ratios API call
  dict_autotrainer: introduce sstable_dict_autotrainer
  db/system_keyspace: add query_dict_timestamp
  compress: add ZstdWithDictsCompressor and LZ4WithDictsCompressor
  main: clean up sstable compression dicts after table drops
  sstables/compress: discard hidden compression options after the decompressor is created
  compress: change compressor_ptr from shared_ptr to unique_ptr
  api: add the retrain_dict API call
  storage_service: add some dict-related routines
  main: in compression_dict_updated_callback, recognize and use SSTable compression dicts
  storage_service: add do_sample_sstables()
  messaging_service: add SAMPLE_SSTABLES and ESTIMATE_SSTABLE_VOLUME verbs
  db/system_keyspace: let `system.dicts` helpers be used for dicts other than the RPC compression dict
  raft/group0_state_machine: on `system.dicts` mutations, pass the affected partitition keys to the callback
  database: add sample_data_files()
  database: add take_sstable_set_snapshot()
  compress: teach `lz4_processor` about dictionaries
  compress: teach `zstd_processor` about dictionaries
  sstables: delegate compressor creation to the compressor factory
  sstables: plug an `sstable_compressor_factory` into `sstables_manager`
  sstables: introduce sstable_compressor_factory
  utils/hashers: add get_sha256()
  gms/feature_service: add the SSTABLE_COMPRESSION_DICTS cluster feature
  compress: add hidden dictionary options
  compress: remove `compression_parameters::get_compressor()`
  sstables/compress: remove get_sstable_compressor()
  sstables/compress: move ownership of `compressor` to `sstable::compression`
  compress: remove compressor::option_names()
  compress: clean up the constructor of zstd_processor
  compress: squash zstd.cc into compress.cc
  sstables/compress: break the dependency of `compression_parameters` on `compressor`
  compress.hh: switch compressor::name() from an instance member to a virtual call
  bytes: adapt fmt_hex to std::span<const std::byte>
2025-04-01 12:47:34 +03:00
Pavel Emelyanov
b5a124f60c sstable_directory: Move highest_generation_seen() to distributed_loader.cc
This method is only used by the loader code (and tests). Also, There's the
highest_version_seen() peer that sits in the loader code either.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>

Closes scylladb/scylladb#23324
2025-04-01 09:15:14 +03:00
Michał Chojnowski
10fa4abde7 compress: change compressor_ptr from shared_ptr to unique_ptr
Cleanup patch. After we moved the ownership of compressors
to sstables, compressor objects never have shared lifetime.
`unique_ptr` is more appropriate for them than `shared_ptr` now.
(And besides expressing the intent better, using `unique_ptr`
prevents an accidental cross-shard `shared_ptr` copy).
2025-04-01 00:07:29 +02:00
Michał Chojnowski
11be7c0704 compress: remove compression_parameters::get_compressor()
Following up on the previous commits, we avoid constructing
compressors where not necessary,
by checking things directly on `compression_parameters` instead.
2025-04-01 00:07:28 +02:00
Michał Chojnowski
8e611536b0 sstables/compress: move ownership of compressor to sstable::compression
SSTable readers and writers use `compressor` objects to compress and
decompress chunks of SSTable data files.

`compressor` objects are read-only, so only one of them is needed
for each SSTable. Before this commit, each reader and writer has
its own `compressor` object. This isn't necessary, but it's okay.

But later in this series it will stop being okay, because the creation
of a `compressor` will become an expensive cross-shard
operation (because it might require sharing a compression dictionary
from another shard). So we have to adjust the code so that there is
only once `compressor` per sstable, not one per reader/writer.

We stuff the ownership of this compressor into `sstable::compression`.

To make the ownership clear, we remove `compression_ptr` shared
pointers from readers and writers, and make them access the
compressor via the `sstable::compression` instead.
2025-04-01 00:07:27 +02:00
Michał Chojnowski
cfe69e057f sstables/compress: break the dependency of compression_parameters on compressor
Note: this commit is meant to be a code refactoring only and is not intended
to change the observable behaviour.

Today `schema` contains a `compression_parameters`.
`compression_parameters` contains an instance of
`compressor`, and SSTable writers just share that instance.

This is fine because `compressor` is a stateless object,
functionally dependent on the schema.

But in later parts of the series, we will break this functional
dependency by adding dictionaries to compressors. Two writers
for the same schema might have different dictionaries, so they won't
be able to just share a single instance contained in the schema.

And when that happens, having a `compressor` instance
in the `schema`/`compression_parameters` will become awkward,
since it won't be actually used. It will be only a container for options.

In addition, for performance reasons, we will want to share some pieces
of compressors across shards, which will require -- in the general case --
a construction of a compressor to be asynchronous, and therefore not
possible inside the constructor of `compression_parameters`.

This commit modifies `compression_parameters` so that it doesn't hold or
construct instances of `compressor`.

Before this patch, the `compressor` instance constructed in
`compression_parameters` has an additional role of validating and
holding compressor-specific options.
(Today the only such option is the zstd compression level).

This means that the pieces of logic responsible for compressor-specific
options have to be rewritten. That ends up being the bulk of this commit.
2025-04-01 00:07:27 +02:00
Robert Bindar
b647196121 Remove db::config::object_storage_config
That map became redundant once we added
object_storage_endpoints in the config, this patch removes
it and switches all the user code to use the new option.

Signed-off-by: Robert Bindar <robert.bindar@scylladb.com>
2025-03-31 17:15:12 +03:00
Tomasz Grabiec
6bff596fce tablets: Make tablet allocation equalize per-shard load
Before, it was equalizing per-node load (tablet count), which is wrong
in heterogenous clusters. Nodes with fewer shards will end up with
overloaded shards.

Refs #23378
2025-03-31 14:34:30 +02:00
Botond Dénes
90c20858ed Merge 'test/database: Remove most of take_snapshot() helper overloads and re-use them more' from Pavel Emelyanov
This helper facilitate snapshot creation by various test cases in database_test.cc. This PR generalizes all overloads into one that suits all callers and patches one more test case to use it as well.

Closes scylladb/scylladb#23482

* github.com:scylladb/scylladb:
  test/database: Re-use take_snapshot() helper once more
  test/database: Remove most of take_snapshot() helper overloads
2025-03-31 15:20:51 +03:00
Benny Halevy
5f2ce0b022 loading_cache_test: test_loading_cache_reload_during_eviction: use manual_clock
Rather than lowres_clock, as since
32b7cab917,
loading_cache_for_test uses manual_clock for timing
and relying on lowres_clock to time the test might
run out of memory on fast test machines.

Fixes #23497

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>

Closes scylladb/scylladb#23498
2025-03-31 14:53:06 +03:00
Pavel Emelyanov
ac582efb44 test/database: Re-use take_snapshot() helper once more
There's a test case that can call the recently patched take_snapshot()
helper as well. This changes nothing, but makes further patching a bit
simpler (not in this branch).

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2025-03-31 13:18:06 +03:00
Pavel Emelyanov
7e6380b6bd test/database: Remove most of take_snapshot() helper overloads
There are 3 of those that help tests (re)shuffle cql_test_env/database,
skip_flush == true/false options and keyspace/table/snapshot names.
There's little sense in having that many of those, just one overload
with default arguments suits most of the callers.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2025-03-31 13:18:06 +03:00
Evgeniy Naydanov
c4ae4e247a test.py: refactor paths constants and options
Add path constants to `test` module and use them in different test suites
instead of own dups of the same code:

 - TOP_SRC_DIR : ScyllaDB's source code root directory
 - TEST_DIR : the directory with test.py tests and libs
 - BUILD_DIR : directory with ScyllaDB's build artefacts

Add TestSuite.log_dir attribute as a ScyllaDB's build mode subdir of a path
provided using `--tmpdir` CLI argument.  Don't use `tmpdir` name because it
mixed up with pytest's built-in fixture and `--tmpdir` option itself.

Change default value for `--tmdir` from `./testlog` to `TOP_SRC_DIR/testlog`

Refactor `ResourceGather*` classes to use path from a `test` object instead of
providing it separately.

Move modes constants to `test` module and remove duplications.

Move `prepare_dirs()` and `start_3rd_party_services()` from `pylib.util` to
`pylib.suite.base` to avoid circular imports (with little refactoring to
use `pathlib.Path` instead of `str` as paths.)

Also, in some places refactor to use f-strings for formatting.
2025-03-30 03:19:29 +00:00
Piotr Dulikowski
288216a89e Merge 'Ignore wrapped exceptions gate_closed_exception and rpc::closed_error when node shuts down.' from Sergey Zolotukhin
Normally, when a node is shutting down, `gate_closed_exception` and `rpc::closed_error`
in `send_to_live_endpoints` should be ignored. However, if these exceptions are wrapped
in a `nested_exception`, an error message is printed, causing tests to fail.

This commit adds handling for nested exceptions in this case to prevent unnecessary
error messages.

Fixes scylladb/scylladb#23325
Fixes scylladb/scylladb#23305
Fixes scylladb/scylladb#21815

Backport: looks like this is quite a frequent issue, therefore backport to 2025.1.

Closes scylladb/scylladb#23336

* github.com:scylladb/scylladb:
  database: Pass schema_ptr as const ref in `wrap_commitlog_add_error`
  database: Unify exception handling in `do_apply` and `apply_with_commitlog`
  storage_proxy: Ignore wrapped `gate_closed_exception` and `rpc::closed_error` when node shuts down.
  exceptions: Add `try_catch_nested` to universally handle nested exceptions of the same type.
2025-03-27 11:39:42 +01:00
Sergey Zolotukhin
6abfed9817 exceptions: Add try_catch_nested to universally handle nested exceptions of the same type. 2025-03-26 11:15:13 +01:00
Benny Halevy
9fac0045d1 boost/tablets_test: verify failure to create keyspace with tablets and non network replication strategy
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2025-03-24 15:39:53 +02:00
Benny Halevy
62aeba759b tablets: enforce tablets using tablets_mode_for_new_keyspaces=enforced config option
`tablets_mode_for_new_keyspaces=enforced` enables tablets by default for
new keyspaces, like `tablets_mode_for_new_keyspaces=enabled`.
However, it does not allow to opt-out when creating
new keyspaces by setting `tablets = {'enabled': false}`.

Refs scylladb/scylla-enterprise#4355

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2025-03-24 15:32:16 +02:00
Benny Halevy
c62865df90 db/config: add tablets_mode_for_new_keyspaces option
The new option deprecates the existing `enable_tablets` option.
It will be extended in the next patch with a 3rd value: "enforced"
while will enable tablets by default for new keyspace but
without the posibility to opt out using the `tablets = {'enabled':
false}` keyspace schema option.

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2025-03-24 14:54:45 +02:00
Avi Kivity
cc5fe542ed test: ignore unused fmt::to_string() result
fmt 11.1 apparently marks to_string() as [[nodiscard]]. Here we aren't
interested in the result, so explicitly ignore it to avoid an error.

Closes scylladb/scylladb#23403
2025-03-24 10:19:09 +03:00
Avi Kivity
cd04ab1a4e test: avoid spaces when defining user-defined literal operator
Clang 20 complains when it sees a user-defined literal operator
defined with a space before the underscore. Assume it's adhering
to the standard and comply.

Closes scylladb/scylladb#23401
2025-03-24 10:17:12 +03:00
Pavel Emelyanov
d436fb8045 Merge 'Fix EAR not applied on write to S3 (but on read).' from Calle Wilund
Fixes #23225
Fixes #23185

Adds a "wrap_sink" (with default implementation) to sstables::file_io_extension, and moves
extension wrapping of file and sink objects to storage level.
(Wrapping/handling on sstable level would be problematic, because for file storage we typically re-use the sstable file objects for sinks, whereas for S3 we do not).

This ensures we apply encryption on both read and write, whereas we previously only did so on read -> fail.
Adds io wrapper objects for adapting file/sink for default implementation, as well as a proper encrypted sink implementation for EAR.

Unit tests for io objects and a macro test for S3 encrypted storage included.

Closes scylladb/scylladb#23261

* github.com:scylladb/scylladb:
  encryption: Add "wrap_sink" to encryption sstable extension
  encrypted_file_impl: Add encrypted_data_sink
  sstables::storage: Move wrapping sstable components to storage provider
  sstables::file_io_extension: Add a "wrap_sink" method.
  sstables::file_io_extension: Make sstable argument to "wrap" const
  utils: Add "io-wrappers", useful IO helper types
2025-03-24 10:12:46 +03:00
Pavel Emelyanov
bd313c581f test: Add unit test for newly introduced download source
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2025-03-21 12:01:06 +03:00
Calle Wilund
9ac9813c62 encrypted_file_impl: Add encrypted_data_sink
Adds a sibling type to encrypted file, a data_sink, that
will write a data stream in the same block format as a file
object would. Including end padding.

For making encrypted data sink writing less cumbersome.
2025-03-20 14:54:24 +00:00
Calle Wilund
e100af5280 sstables::file_io_extension: Make sstable argument to "wrap" const
This matches the signature of call sites. Since the only "real"
extension to actually make a marker in the sstable will do so in
the scylla component, which is writable even in a const sstable,
this is ok.
2025-03-20 14:54:09 +00:00
Calle Wilund
98a6d0f79c utils: Add "io-wrappers", useful IO helper types
Mainly to add a somewhat functional file-impl wrapping
a data_sink. This can implement a rudimentary, write-only,
file based on any output sink.

For testing, and because they fit there, place memory
sink and source types there as well.
2025-03-20 14:54:09 +00:00
Botond Dénes
d06bc27979 Merge 'Don't export string filenames from sstable' from Pavel Emelyanov
There are several sstring-returning methods on class sstable that return paths to files. Mostly these are used to print them into logs, sometimes are used to be put into exception messages. And there are places that use these strings as file names. Since now sstables can also be stored on S3, generic code shouldn't consider those strings as on disk file names.

Other than that, even when the methods are used to put component names into logs, in many cases these log messages come with debug or trace level, so generated strings are immediately dropped on the floor, but generating it is not extremely cheap. Code would benefit from using lazily-printed names.

This change introduces the component_name struct that wraps sstable reference and component ID (which is a numerical enum of several items). When printed, the component_name formatter calls the aforementioned filename generation, thus implementing lazy printing. And since there's no automatic conversion of component_name-s into strings, all the code that treats them as file paths, becomes explicit.

refs: #14122 (previous ugly attempt to achieve the same goal)

Closes scylladb/scylladb#23194

* github.com:scylladb/scylladb:
  sstable: Remove unused malformed_sstable_exctpion(string filename)
  sstables: Make filename() return component_name
  sstables: Make file_writer keep component_name on board
  sstables: Make get_filename() return component_name
  sstables: Make toc_filename() return component_name
  sstables: Make sstable::index_filename() return component_name
  sstables: Introduce struct component_name
  sstables: Remove unused sstable::component_filenames() method
  sstables: Do not print component filenames on load-and-stream wrap-up
  sstables: Explicitly format prefix in S3 object name making
  sstables: Don't include directory name in exception
  sstables: Use fmt::format instead of string concatenation
  sstables: Rename filename($component) calls to ${component}_filename()
  sstables: Rename local filename variable to component_name
2025-03-20 09:51:03 +02:00
Avi Kivity
a62ab824e6 schema: deprecate schema_extension
schema_extension allows making invisible changes to system_schema
that evade upgrade rollback tests. They appear in system_schema
as an encoded blob which reduces serviceability, as they cannot
be read.

Deprecate it and point users to adding explicit columns in scylla_tables.

We could probably make use of the data structure, after we teach it
to encode its payload into proper named and typed columns instead of
using IDL.

Closes scylladb/scylladb#23151
2025-03-19 20:36:16 +02:00
Pavel Emelyanov
1ba91e28cb sstables: Make get_filename() return component_name
Similarly to previous patches -- mostly the result is used as log
argument. The remaining users include

- scylla sstable tool that dumps component names to json output
- API endpoint that returns component names to user
- tests

these are all good to explicitly convert component_names to strings.

There are few more places that expect strings instead of component name
objects. For now they also use fmt::to_string() explicitly, partially it
will be fixed later, mostly -- as future follow-ups.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2025-03-19 13:03:29 +03:00
Pavel Emelyanov
420b5bee20 test/s3: Increase boost/s3_test log levels
When something goes wrong, it's impossible to find anyting out without
s3 and http logs, so increase them for boost tests.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>

Closes scylladb/scylladb#23245
2025-03-18 15:59:05 +02:00
Botond Dénes
2795d83b32 Merge 'commitlog: Serialize file deletion and distribute replayed segments' from Calle Wilund
Fixes #23017

When deleting segments while our footprint is over the limit, mainly when recycling/deleting segments after replay (recover boot) we can cause two deletion passes to be running at the same time. This is because delete is triggered by either

a.) replay release
b.) timer check (explicit)
c.) timer initiated flush callback

where the last one is in fact not even waited for. If we are considering many files for delete/recycle, we can, due to task switch, end up considering segments ok to keep, in parallel, even though one of them should be deleted. The end result will be us keeping one more segment than should be allowed.

Now, eventually, this should be released, once we do deletion again, but this can take a while.

Solution is to simply ensure we serialize deletion. This might cause some delay in processing cycles for recycle, but in practice, this should never happen when we are in fact under pressure.

As noted in the issue above, when replaying a large commitlog from an unclean node, we can cause shard 0
db commitlog to reach footprint limit, and then remain there (because we never release segments lower than limit). This is wasteful with diskspace. But deleting segments early here is also wasteful; A better solution is
to simply give the segments to all CL shards, thus distributing the available space.

Closes scylladb/scylladb#23150

* github.com:scylladb/scylladb:
  main/commitlog: wait for file deletion and distribute recycled segments to shards
  commitlog: Serialize file deletion
2025-03-18 11:47:17 +02:00
Calle Wilund
4ed81e05bf commitlog: Serialize file deletion
Fixes #23017

When deleting segments while our footprint is over the limit,
mainly when recycling/deleting segments after replay (recover
boot) we can cause two deletion passes to be running at the same
time. This is because delete is triggered by either

a.) replay release
b.) timer check (explicit)
c.) timer initiated flush callback

where the last one is in fact not even waited for. If we are
considering many files for delete/recycle, we can, due to task
switch, end up considering segments ok to keep, in parallel,
even though one of them should be deleted. The end result
will be us keeping one more segment than should be allowed.
Now, eventually, this should be released, once we do deletion
again, but this can take a while.

Solution is to simply ensure we serialize deletion. This might
cause some delay in processing cycles for recycle, but in
practice, this should never happen when we are in fact under
pressure.

Small unit test included.
2025-03-17 12:09:00 +00:00
Avi Kivity
4416b0c732 treewide: use angle brackets for including seastar headers
Seastar is an external library, so we use angle brackets to
include its interfaces.

Closes scylladb/scylladb#23301
2025-03-17 10:03:06 +02:00
Raphael S. Carvalho
e9944f0b7c service: Introduce rack-aware co-location migrations for tablet merge
Merge co-location can emit migrations across racks even when RF=#racks,
reducing availability and affecting consistency of base-view pairing.

Given replica set of sibling tablets T0 and T1 below:
[T0: (rack1,rack3,rack2)]
[T1: (rack2,rack1,rack3)]

Merge will co-locate T1:rack2 into T0:rack1, T1 will be temporarily only at
only a subset of racks, reducing availability.

This is the main problem fixed by this patch.

It also lays the ground for consistent base-view replica pairing,
which is rack-based. For tables on which views can be created we plan
to enforce the constraint that replicas don't move across racks and
that all tablets use the same set of racks (RF=#racks). This patch
avoids moving replicas across racks unless it's necessary, so if the
constraint is satisfied before merge, there will be no co-locating
migrations across racks. This constraint of RF=#racks is not enforced
yet, it requires more extensive changes.

Fixes #22994.
Refs #17265.

This patch is based on Raphael's work done in PR #23081. The main differences are:

1) Instead of sorting replicas by rack, we try to find
    replicas in sibling tablets which belong to the same rack.
    This is similar to how we match replicas within the same host.
    It reduces number of across-rack migrations even if RF!=#racks,
    which the original patch didn't handle.
    Unlike the original patch, it also avoids rack-overloaded in case
    RF!=#racks

2) We emit across-rack co-locating migrations if we have no other choice
   in order to finalize the merge

   This is ok, since views are not supported with tablets yet. Later,
   we will disallow this for tables which have views, and we will
   allow creating views in the first place only when no such migrations
   can happen (RF=#racks).

3) Added boost unit test which checks that rack overload is avoided during merge
   in case RF<#racks

4) Moved logging of across-rack migration to debug level

5) Exposed metric for across-rack co-locating migrations

Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Signed-off-by: Tomasz Grabiec <tgrabiec@scylladb.com>

Closes scylladb/scylladb#23247
2025-03-16 22:45:00 +02:00
Botond Dénes
39bcf99f8e Merge 'Apply hard limit to partition range vectors in secondary index queries' from Nikos Dragazis
Secondary index queries fetch partition keys from the index view and store them in an `std::vector`. The vector size is currently limited by the user's page size and the page memory limit (1MiB). These are not enough to prevent large contiguous allocations (which can lead to stalls).

This series introduces a hard limit to the vector size to ensure it does not exceed the allocator's preferred max contiguous allocation size (128KiB). With the size of each element being 120 bytes, this allows for 1092 partition keys. The limit was set to 1000. Any partitions above this limit are discarded.

Discarding partitions breaks the querier cache on the replicas, causing a performance regression, as can be seen from the following measurements:
```
* Cluster: 3 nodes (local Docker containers), 1 vCPU, 4GB memory, dev mode
* Schema:
  CREATE KEYSPACE ks WITH replication = {'class': 'org.apache.cassandra.locator.NetworkTopologyStrategy', 'datacenter1': '3'} AND durable_writes = true AND tablets = {'enabled': false};
  CREATE TABLE ks.t1 (pk1 int, pk2 int, ck int, value int, PRIMARY KEY ((pk1, pk2), ck));
  CREATE INDEX t1_pk2_idx ON ks.t1(pk2);
* Query: CONSISTENCY LOCAL_QUORUM; SELECT * FROM ks.t1 where pk2 = 1;

+------------+-------------------+-------------------+
|  Page Size |      Master       |   Vector Limit    |
+============+===================+===================+
|            |   Latency (sec)   |   Latency (sec)   |
+------------+-------------------+-------------------+
|     100    |  5.80 ± 0.13      |  5.64 ± 0.10      |
+------------+-------------------+-------------------+
|    1000    |  4.77 ± 0.07      |  4.62 ± 0.06      |
+------------+-------------------+-------------------+
|    2000    |  4.67 ± 0.07      |  5.13 ± 0.03      |
+------------+-------------------+-------------------+
|    5000    |  4.82 ± 0.09      |  6.25 ± 0.06      |
+------------+-------------------+-------------------+
|   10000    |  4.89 ± 0.36      |  7.52 ± 0.13      |
+------------+-------------------+-------------------+
|     -1     |  4.90 ± 0.67      |  4.79 ± 0.33      |
+------------+-------------------+-------------------+
```
We expect this to be fixed with adaptive paging in a future PR. Until then, users can avoid regressions by adjusting their page size.

Additionally, this series changes the `untyped_result_set` to store rows in a `chunked_vector` instead of an `std::vector`, similarly to the `result_set`. Secondary index queries use an `untyped_result_set` to store the raw result from the index view before processing. With 1MiB results, the `std::vector` would cause a large allocation of this magnitude.

Finally, a unit test is added to reproduce the bug.

Fixes #18536.

The PR fixes stalls of up to 100ms, but there is an easy workaround: adjust the page size. No need to backport.

Closes scylladb/scylladb#22682

* github.com:scylladb/scylladb:
  cql3: secondary index: Limit page size for single-row partitions
  cql3: secondary index: Limit the size of partition range vectors
  cql3: untyped_result_set: Store rows in chunked_vector
  test: Reproduce bug with large allocations from secondary index
2025-03-14 15:06:07 +02:00
Botond Dénes
83ea1877ab Merge 'scylla-sstable: add native S3 support' from Ernest Zaslavsky
scylla-sstable: Enable support for S3-stored sstables

Minimal implementation of what was mentioned in this [issue](https://github.com/scylladb/scylladb/issues/20532)

This update allows Scylla to work with sstables stored on AWS S3. Users can specify the fully qualified location of the sstable using the format: `s3://bucket/prefix/sstable_name`. One should have `object_storage_config_file` referenced in the `scylla.yaml` as described in docs/operating-scylla/admin.rst

ref: https://github.com/scylladb/scylladb/issues/20532
fixes: https://github.com/scylladb/scylladb/issues/20535

No backport needed since the S3 functionality was never released

Closes scylladb/scylladb#22321

* github.com:scylladb/scylladb:
  tests: Add Tests for Scylla-SSTable S3 Functionality
  docs: Update Scylla Tools Documentation for S3 SSTable Support
  scylla-sstable: Enable Support for S3 SSTables
  s3: Implement S3 Fully Qualified Name Manipulation Functions
  object_storage: Refactor `object_storage.yaml` parsing logic
2025-03-14 15:05:52 +02:00
Pavel Emelyanov
2bb455ec75 Merge 'Main: stop system_keyspace' from Benny Halevy
This series adds an async guard to system_keyspace operations
and adds a deferred action to stop the system_keyspace in main() before destroying the service.

This helps to make sure that sys_ks is unplugged from its users and that all async operations using it are drained once it's stopped.

* Enhancement, no backport needed

Closes scylladb/scylladb#23113

* github.com:scylladb/scylladb:
  main: stop system keyspace
  system_keyspace: call shutdown from stop
  system_keyspace: shutdown: allow calling more than once
  database, compaction_manager, large_data_handler: use pluggable<system_keysapce>
  utils: add class pluggable
2025-03-14 13:23:28 +03:00
Kefu Chai
31320399e8 test: sstable_test: use auto instead of statistics to avoid name collision
Replace explicit `statistics` type with `auto` in sstable_test to
resolve name collision. This addresses ambiguity introduced by commit
87c221cb which added `struct statistics` in
`seastar/include/seastar/net/api.hh`, conflicting with the existing
definition in `scylladb/sstables/types.hh` when the `seastar` namespace
is opened.

The `auto` keyword avoids the need to explicitly reference either type,
cleanly resolving the collision while maintaining functionality.
This change prepares for the upcoming change to bump up seastar
submodule.

Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>

Closes scylladb/scylladb#23249
2025-03-13 22:51:21 +02:00
Avi Kivity
b1d9f80d85 Merge 'tablets: Make load balancing capacity-aware' from Tomasz Grabiec
Before this patch, the load balancer was equalizing tablet count per
shard, so it achieved balance assuming that:
 1) tablets have the same size
 2) shards have the same capacity

That can cause imbalance of utilization if shards have different
capacity, which can happen in heterogeneous clusters with different
instance types. One of the causes for capacity difference is that
larger instances run with fewer shards due to vCPUs being dedicated to
IRQ handling. This makes those shards have more disk capacity, and
more CPU power.

After this patch, the load balancer equalizes shard's storage
utilization, so it no longer assumes that shards have the same
capacity. It still assumes that each tablet has equal size. So it's a
middle step towards full size-aware balancing.

One consequence is that to be able to balance, the load balancer need
to know about every node's capacity, which is collected with the same
RPC which collects load_stats for average tablet size. This is not a
significant set back because migrations cannot proceed anyway if nodes
are down due to barriers. We could make intra-node migration
scheduling work without capacity information, but it's pointless due
to above, so not implemented.

Also, per-shard goal for tablet count is still the same for all nodes in the cluster,
so nodes with less capacity will be below limit and nodes with more capacity will
be slightly above limit. This shouldn't be a significant problem in practice, we could
compensate for this by increasing the limit.

Refs #23042

Closes scylladb/scylladb#23079

* github.com:scylladb/scylladb:
  tablets: Make load balancing capacity-aware
  topology_coordinator: Fix confusing log message
  topology_coordinator: Refresh load stats after adding a new node
  topology_coordinator: Allow capacity stats to be refreshed with some nodes down
  topology_coordinator: Refactor load status refreshing so that it can be triggered from multiple places
  test: boost: tablets_test: Always provide capacity in load_stats
  test: perf_load_balancing: Set node capacity
  test: perf_load_balancing: Convert to topology_builder
  config, disk_space_monitor: Allow overriding capacity via config
  storage_service, tablets: Collect per-node capacity in load_stats
2025-03-11 14:34:27 +02:00
Nikos Dragazis
76b31a3acc cql3: secondary index: Limit the size of partition range vectors
The partition range vector is an std::vector, which means it performs
contiguous allocations. Large allocations are known to cause problems
(e.g., reactor stalls).

For paged queries, limit the vector size to 1000. If more partition keys
are available in the query result, discard them. Ideally, we should not
be fetching them at all, but this is not possible without knowing the
size of each partition.

Currently, each vector element is 120 bytes and the standard allocator's
max preferred contiguous allocation is 128KiB. Therefore, the chosen
value of 1000 satisfies the constraint (128 KiB / 120 = 1092 > 1000).
This should be good enough for most cases. Since secondary index queries
involve one base table query per partition key, these queries are slow.
A higher limit would only make them slower and increase the probability
of a timeout. For the same reason, saving a follow-up paged request from
the client would not increase the efficiency much.

For unpaged queries, do not apply any limit. This means they remain
susceptible to stalls, but unpaged queries are considered unoptimized
anyway.

Finally, update the unit test reproducer since the bug is now fixed.

Signed-off-by: Nikos Dragazis <nikolaos.dragazis@scylladb.com>
2025-03-10 12:18:42 +02:00
Ernest Zaslavsky
88c4fa6569 s3: Implement S3 Fully Qualified Name Manipulation Functions
Added utility functions to handle S3 Fully Qualified Names (FQN). These
functions enable parsing, splitting, and identification of S3 paths,
enhancing our ability to work with S3 object storage more effectively.
2025-03-09 09:50:36 +02:00
Robert Bindar
27f2d64725 Remove object storage config credentials provider
During development of #22428 we decided that we have
no need for `object-storage.yaml`, and we'd rather store
the endpoints in `scylla.yaml` and get a REST api to exopose
the endpoints for free.
This patch removes the credentials provider used to read the
aws keys from this yaml file.
Followup work will remove the `object-storage.yaml` file
altogether and move the endpoints to `scylla.yaml`.

Signed-off-by: Robert Bindar <robert.bindar@scylladb.com>

Closes scylladb/scylladb#22951
2025-03-07 10:40:58 +03:00
Tomasz Grabiec
c4714180cc tablets: Make load balancing capacity-aware
Before this patch the load balancer was equalizing tablet count per
shard, so it achieved balance assuming that:
 1) tablets have the same size
 2) shards have the same capacity

That can cause imbalance of utilization if shards have different
capacity, which can happen in heterogenous clusters with different
instance types. One of the causes for capacity difference is that
larger instances run with fewer shards due to vCPUs being dedicated to
IRQ handling. This makes those shards have more disk capacity, and
more CPU power.

After this patch, the load balancer equalizes shard's storage
utilization, so it no longer assumes that shards have the same
capacity. It still assummes that each tablet has equal size. So it's a
middle step towards full size-aware balancing.

One consequence is that to be able to balance, the load balancer need
to know about every node's capacity, which is collected with the same
RPC which collects load_stats for average tablet size. This is not a
significant set back because migrations cannot proceed anyway if nodes
are down due to barriers. We could make intra-node migration
scheduling work without capacity information, but it's pointless due
to above, so not implemented.
2025-03-06 13:35:38 +01:00
Tomasz Grabiec
69c49fb1a7 test: boost: tablets_test: Always provide capacity in load_stats
Move shared_load_stats to topology_builder.hh so that topology_builder
can maintain it. It will set capacity for all created nodes. Needed
after load balancer requires capacity to make decisions.
2025-03-06 13:35:37 +01:00
Tomasz Grabiec
d01cc16d1e config, disk_space_monitor: Allow overriding capacity via config
Intended for testing, or hot-fixing out-of-space issues in production.

Tablet load balancer uses this information for determining per-shard load
so reducing capacity will cause tablets to be migrated away from the node.
2025-03-06 13:35:37 +01:00
Benny Halevy
13a22cb6fd utils: add class pluggable
A wrapper around a shared service allowing
safe plug and unplug of the service from its user
using a phased-barrier operation permit guarding
the service while in use.

Also add a unit test for this class.

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2025-03-05 08:25:50 +02:00