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
Document the new `components_digests` subcomponent (tag 12) added to the
Scylla.db metadata component, which stores CRC32 digests of all checksummed
SSTable component files. Also document the trailing CRC32 digest that
stores digest of the scylla metadata itself.
In this series we introduce new system tables and use them for storing the raft metadata
for strongly consistent tables. In contrast to the previously used raft group0 tables, the
new tables can store data on any shard. The tables also allow specifying the shard where
each partition should reside, which enables the tablets of strongly consistent tables to have
their raft group metadata co-located on the same shard as the tablet replica.
The new tables have almost the same schemas as the raft group0 tables. However, they
have an additional column in their partition keys. The additional column is the shard
that specifies where the data should be located. While a tablet and its corresponding
raft group server resides on some shard, it now writes and reads all requests to the
metadata tables using its shard in addition to the group_id.
The extra partition key column is used by the new partitioner and sharder which allow
this special shard routing. The partitioner encodes the shard in the token and the
sharder decodes the shard from the token. This approach for routing avoids any
additional lookups (for the tablet mapping) during operations on the new tables
and it also doesn't require keeping any state. It also doesn't interact negatively
with resharding - as long as tablets (and their corresponding raft metadata) occupy
some shard, we do not allow starting the node with a shard count lower than the
id of this shard. When increasing the shard count, the routing does not change,
similarly to how tablet allocation doesn't change.
To use the new tables, a new implementation of `raft::persistence` is added. Currently,
it's almost an exact copy of the `raft_sys_table_storage` which just uses the new tables,
but in the future we can modify it with changes specific to metadata (or mutation)
storage for strongly consistent tables. The new storage is used in the `groups_manager`,
which combined with the removal of some `this_shard_id() == 0` checks, allows strongly
consistent tables to be used on all shards.
This approach for making sure that the reads/writes to the new tables end up on the correct shards
won in the balance of complexity/usability/performance against a few other approaches we've considered.
They include:
1. Making the Raft server read/write directly to the database, skipping the sharder, on its shard, while using
the default partitioner/sharder. This approach could let us avoid changing the schema and there should be
no problems for reads and writes performed by the Raft server. However, in this approach we would input
data in tables conflicting with the placement determined by the sharder. As a result, any read going through
the sharder could miss the rows it was supposed to read. Even when reading all shards to find a specific value,
there is a risk of polluting the cache - the rows loaded on incorrect shards may persist in the cache for an unknown
amount of time. The cache may also mistakenly remember that a row is missing, even though it's actually present,
just on an incorrect shard.
Some of the issues with this approach could be worked around using another sharder which always returns
this_shard_id() when asked about a shard. It's not clear how such a sharder would implement a method like
`token_for_next_shard`, and how much simpler it would be compared to the current "identity" sharder.
2. Using a sharder depending on the current allocation of tablets on the node. This approach relies on the
knowledge of group_id -> shard mapping at any point in time in the cluster. For this approach we'd also
need to either add a custom partitioner which encodes the group_id in the token, or we'd need to track the
token(group_id) -> shard mapping. This approach has the benefit over the one used in the series of keeping
the partition key as just group_id. However, it requires more logic, and the access to the live state of the node
in the sharder, and it's not static - the same token may be sharded differently depending on the state of the
node - it shouldn't occur in practice, but if we changed the state of the node before adjusting the table data,
we would be unable to access/fix the stale data without artificially also changing the state of the node.
3. Using metadata tables co-located to the strongly consistent tables. This approach could simplify the
metadata migrations in the future, however it would require additional schema management of all co-located
metadata tables, and it's not even obvious what could be used as the partition key in these tables - some
metadata is per-raft-group, so we couldn't reuse the partition key of the strongly consistent table for it. And
finding and remembering a partition key that is routed to a specific shard is not a simple task. Finally, splits
and merges will most likely need special handling for metadata anyway, so we wouldn't even make use of
co-located table's splits and merges.
Fixes [SCYLLADB-361](https://scylladb.atlassian.net/browse/SCYLLADB-361)
[SCYLLADB-361]: https://scylladb.atlassian.net/browse/SCYLLADB-361?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQClosesscylladb/scylladb#28509
* github.com:scylladb/scylladb:
docs: add strong consistency doc
test/cluster: add tests for strongly-consistent tables' metadata persistence
raft: enable multi-shard raft groups for strongly consistent tablets
test/raft: add unit tests for raft_groups_storage
raft: add raft_groups_storage persistence class
db: add system tables for strongly consistent tables' raft groups
dht: add fixed_shard_partitioner and fixed_shard_sharder
raft: add group_id -> shard mapping to raft_group_registry
schema: add with_sharder overload accepting static_sharder reference
Fixes issue #12818 with the following docs changes:
docs/dev/system_keyspace.md: Added missing system tables, added table of contents (TOC), added categories
Closesscylladb/scylladb#27789
Introduced a new max_tablet_count tablet option that caps the maximum number of tablets a table can have. This feature is designed primarily for backup and restore workflows.
During backup, when load balancing is disabled for snapshot consistency, the current tablet count is recorded in the backup manifest.
During restore, max_tablet_count is set to this recorded value, ensuring the restored table's tablet count never exceeds the original snapshot's tablet distribution.
This guarantee enables efficient file-based SSTable streaming during restore, as each SSTable remains fully contained within a single tablet boundary.
Closesscylladb/scylladb#28450
Add a new docs/dev document for the strongly consistent tables feature.
For now, it only contains information about the Raft metadata persistence,
but it should be updated as more of the strong-consistency components are
added.
https://github.com/scylladb/scylladb/pull/25746 added a new column to `system.clients`: `client_options frozen<map<text, text>>`. This column stores all options sent by the client in the `STARTUP` message.
This PR also added `CLIENT_OPTIONS` to the list of values sent in `SUPPORTED` message, and documented that drivers can send their configuration (as JSON) in `STARTUP` under this key.
Documentation for the new column was not added to the description of `system.clients` table, and documentation about the new `STARTUP` key was added in `protocol-extensions.md`, but in the section about shard awareness extension.
This PR adds missing `system.clients` column description, moves the documentation of `CLIENT_OPTIONS` into its own section, and expands it a bit.
Backport: none, because this fixes internal documentation.
Closesscylladb/scylladb#28126
* github.com:scylladb/scylladb:
protocol-extensions.md: Fix client_options docs
system_keyspace.md: Add client_options column
system_keyspace.md: Fix order in system.clients
This commit replaces the previous approach of running pytest inside
GDB’s Python interpreter. Instead, tests are executed by driving a
persistent GDB process externally using pexpect.
- pexpect: Python library for controlling interactive programs
(used here to send commands to GDB and capture its output)
- persistent GDB: keep one GDB session alive across multiple tests
instead of starting a new process for each test
Tests can now be executed via `./test.py gdb` or with
`pytest test/scylla_gdb`. This improves performance and
makes failures easier to debug since pytest no longer runs
hidden inside GDB subprocesses.
Closesscylladb/scylladb#24804
A permit gets into the preemptive_aborted state when:
- times out;
- gets rejected from execution due to high chance its execution would
not finalize on time;
Being in this state means a permit was removed from the wait list,
its internal timer was canceled and semaphore's statistic
`total_reads_shed_due_to_overload` increased.
Allows other topology operations to execute while tablets are being
drained on decommission. In particular, bootstrap on scale-out. This
is important for elasticity.
Allows multiple decommission/removenode to happen in parallel, which
is important for efficiency.
Flow of decommission/removenode request:
1) pending and paused, has tablet replicas on target node.
Tablet scheduler will start draining tablets.
2) No tablets on target node, request is pending but not paused
3) Request is scheduled, node is in transition
4) Request is done
Nodes are considered draining as soon as there is a leave or remove
request on them. If there are tablet replicas present on the target
node, the request is in a paused state and will not be picked by
topology coordinator. The paused state is computed from topology state
automatically on reload.
When request is not paused, its execution starts in
write_both_read_old state. The old tablet_draining state is not
entered (it's deprecated now).
Tablet load balancing will yield the state machine as soon as some
request is no longer paused and ready to be scheduled, based on
standard preemption mechanics.
Fixes#21452Closesscylladb/scylladb#24129
* https://github.com/scylladb/scylladb:
docs: Document parallel decommission and removenode and relevant task API
test: Add tests for parallel decommission/removenode
test: util: Introduce ensure_group0_leader_on()
test: tablets: Check that there are no migrations scheduled on draining nodes
test: lib: topology_builder: Introduce add_draining_request()
topology_coordinator, tablets: Fail draining operations when tablet migration fails due to critical disk utilization
tablets: topology_coordinator: Refactor to propagate reason for migration rollback
tablet_allocator: Skip co-location on draining nodes
node_ops: task_manager_module: Populate entity field also for active requests
tasks: node_ops: Put node id in the entity field
tasks, node_ops: Unify setting of task_stats in get_status() and get_stats()
topology: Protect against empty cancelation reason
tasks, topology: Make pending node operations abortable
doc: topology-over-raft.md: Fix diagram for replacing, tablet_draining is not engaged
raft_topology, tablets: Drain tablets in parallel with other topology operations
virtual_tables: Show draining and excluded fields in system.cluster_status and system.load_by_node
locator: topology: Add "draining" flag to a node
topology_coordinator: Extract generate_cancel_request_update()
storage_service: Drop dependency in topology_state_machine.hh in the header
locator: Extract common code in assert_rf_rack_valid_keyspace()
topology_coordinator, storage_service: Validate node removal/decommission at request submission time
Adds a "sstables" array member to manifest.json.
For each sstables, keep the following metadata:
id - a uuid for the sstable (the sstable identifier
if the use-sstable-identifier option was used, otherwise
the sstable uuid generation)
toc_name - the name of the TOC.txt file
data_size and index_size - in bytes
first_token and last_token - of the sstable first and last keys.
Fixes: SCYLLADB-196
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Add a table member to manifest.json with the keyspace_name,
table_name, table_id, tablets_type, and, for tablets-enabled tables, get
tablet_count on each shard and write the minimum to manifest.json.
For vnodes-based tables, tablet_count=0.
For now, `tablets_type` may be either `none` for vnodes tables, or
`powof2` for tablets tables. In the future, when we support arbitrary
tablt boundaries, this will be reflected here, and it is likely we
would backup the whole tablets map sperately to get all tablet boundaries.
Fixes SCYLLADB-195
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Add metadata about the node: host_id, datacenter, and rack.
This enables dc- or rack- aware restore.
Today this information is "encoded" into the snapshot hierarchy
prefixes, but if all manifest files would be stored in a flat
directory, we'd need to encode that metadata in the object name,
but it'd be better for the manifest contents to be self descriptive.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Add metadata about the manifest itself:
A version and the manifest scope (currently "node",
but in the future, may also be "shard", or "tablet")
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Validate the manifest.json format by loading it using rjson::parse
and then validate its contents to ensure it lists exactly the
SSTables present in the snapshot directory.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Allows other topology operations to execute while tablets are being
drained on decommission. In particular, bootstrap on scale-out. This
is important for elasticity.
Allows multiple decommission/removenode to happen in parallel, which
is important for efficiency.
Flow of decommission/removenode request:
1) pending and paused, has tablet replicas on target node.
Tablet scheduler will start draining tablets.
2) No tablets on target node, request is pending but not paused
3) Request is scheduled, node is in transition
4) Request is done
Nodes are considered draining as soon as there is a leave or remove
request on them. If there are tablet replicas present on the target
node, the request is in a paused state and will not be picked by
topology coordinator. The paused state is computed from topology state
automatically on reload.
When request is not paused, its execution starts in
write_both_read_old state. The old tablet_draining state is not
entered (it's deprecated now).
Tablet load balancing will yield the state machine as soon as some
request is no longer paused and ready to be scheduled, based on
standard preemption mechanics.
The test case test_explicit_tablet_movement_during_decommission is
removed. It verifies that tablet move API works during tablet draining
transition. After this PR, we no longer enter this transition, so the
test doesn't work. It loses its purpose, because movement during
normal tablet balancing is not special and tested elsewhere.
0ede8d154b introduced the dev doc for size
based load balancing, but also added spelling errors.
This PR fixed these errors.
Closesscylladb/scylladb#28196
To configure S3 storage, one needs to do
```
object_storage_endpoints:
- name: s3.us-east-1.amazonaws.com
port: 443
https: true
aws_region: us-east-1
```
and for GCS it's
```
object_storage_endpoints:
- name: https://storage.googleapis.com:433
type: gs
credentials_file: <gcp account credentials json file>
```
This PR updates the S3 part to look like
```
object_storage_endpoints:
- name: https://s3.us-east-1.amazonaws.com:443
aws_region: us-east-1
```
fixes: #26570
This is 2nd attempt, previous one (#27360) was reverted because it reported endpoint configs in new format via API and CQL always, even if the endpoint was configured in the old way. This "broke" scylla manager and some dtests. This version has this bug fixed, and endpoints are reported in the same format as they were configured with.
About correctness of the changes.
No modifications to existing tests are made here, so old format is respected correctly (as far as it's covered by tests). To prove the new format works the the test_get_object_store_endpoints is extended to validate both options. Some preparations to this test to make this happen come on their own with the PR #28111 to show that they are valid and pass before changing the core code.
Enhancing the way configuration is made, likely no need to backport.
Closesscylladb/scylladb#28112
* github.com:scylladb/scylladb:
test: Validate S3 endpoints new format works
docs: Update docs according to new endpoints config option format
object_storage: Create s3 client with "extended" endpoint name
s3/storage: Tune config updating
sstable: Shuffle args for s3_client_wrapper
test: Rename badconf variable into objconf
test: Split the object_store/test_get_object_store_endpoints test
When this column and relevant SUPPORTED key were added, the
documentation was mistakenly put in the section about shard awareness
extension. This commit moves the documentation into a dedicated section.
I also expended it to describe both the new column and the new SUPPORTED
key.
Since Scylla 6.0, service levels are manged by Raft group0.
This patch updates table name used by service levels and adds a
paragraph describing service levels on raft.
Fixesscylladb/scylladb#18177Closesscylladb/scylladb#26556
This will move responsibility for running tests with pytest in the same manner as it was done with boost tests. From this commit, test.py is not responsible anymore for running python tests and relies completely on pytest.
This is another step for unification of test execution.
Convert skip_mode function to `pytest.mark` to be able to use to annotate the whole module instead of each test explicitly.
NOTE: this is a breaking change. From this commit, several directories with tests will require a path to the file to launch the test. Affected directories
test/alternator
test/broadcast_tables
test/cql
test/cqlpy
test/rest_api
Changes only in framework, so no backport.
This PR will increase the amount of the tests by 30 test, due to the fact that how test.py and pytest discover tests. test.py count a file as a test, and when skip used in suite.yaml it will exclude the tests from discovery completely.
While the pytest count test funstion as a test and uses skip_mode mark and will discover the tests, but it will skip them during execution, hence the difference
test.py output before PR:
```bash
> ./test.py --mode=release rest_api/test_compaction_task rest_api/test_task_manager --list --no-gather-metrics
```
test.py output in this PR:
```bash
> ./test.py --mode=release test/rest_api/test_compaction_task.py test/rest_api/test_task_manager.py --list
rest_api/test_compaction_task.py::test_global_major_keyspace_compaction_task.release.1
rest_api/test_compaction_task.py::test_major_keyspace_compaction_task.release.1
rest_api/test_compaction_task.py::test_cleanup_keyspace_compaction_task.release.1
rest_api/test_compaction_task.py::test_offstrategy_keyspace_compaction_task.release.1
rest_api/test_compaction_task.py::test_rewrite_sstables_keyspace_compaction_task.release.1
rest_api/test_compaction_task.py::test_reshaping_compaction_task.release.1
rest_api/test_compaction_task.py::test_resharding_compaction_task.release.1
rest_api/test_compaction_task.py::test_regular_compaction_task.release.1
rest_api/test_compaction_task.py::test_compaction_task_abort.release.1
rest_api/test_compaction_task.py::test_major_keyspace_compaction_task_async.release.1
rest_api/test_compaction_task.py::test_cleanup_keyspace_compaction_task_async.release.1
rest_api/test_compaction_task.py::test_offstrategy_keyspace_compaction_task_async.release.1
rest_api/test_compaction_task.py::test_rewrite_sstables_keyspace_compaction_task_async.release.1
rest_api/test_compaction_task.py::test_compaction_progress[major_keyspace_compaction_task_impl_run_fail].release.1
rest_api/test_compaction_task.py::test_compaction_progress[shard_major_keyspace_compaction_task_impl_run_fail].release.1
rest_api/test_compaction_task.py::test_compaction_progress[table_major_keyspace_compaction_task_impl_run_fail].release.1
rest_api/test_task_manager.py::test_task_manager_modules.release.1
rest_api/test_task_manager.py::test_task_manager_tasks.release.1
rest_api/test_task_manager.py::test_task_manager_status_running.release.1
rest_api/test_task_manager.py::test_task_manager_status_done.release.1
rest_api/test_task_manager.py::test_task_manager_status_failed.release.1
rest_api/test_task_manager.py::test_task_manager_not_abortable.release.1
rest_api/test_task_manager.py::test_task_manager_wait.release.1
rest_api/test_task_manager.py::test_task_manager_ttl.release.1
rest_api/test_task_manager.py::test_task_manager_user_ttl.release.1
rest_api/test_task_manager.py::test_task_manager_sequence_number.release.1
rest_api/test_task_manager.py::test_task_manager_recursive_status.release.1
rest_api/test_task_manager.py::test_module_not_exists.release.1
rest_api/test_task_manager.py::test_task_folding.release.1
rest_api/test_task_manager.py::test_abort_on_unregistered_task.release.1
```
Fixes: https://github.com/scylladb/scylladb/issues/27716Closesscylladb/scylladb#26395
* github.com:scylladb/scylladb:
test.py: fix test_vector_similarity.py
docs: add directories excluded from test.py
test.py: prevent file descriptors leaking
test.py: capture print inside the test
test.py: do not print header for collection with test.py
test.py: remove not supported functionality
test.py: switch of execution of several test directories by test.py runner
test.py: integrate python tests to be executed with pytest runner
test.py: fix test/vector_search_validator to be able to run with pytest
test.py: prepare base class for migration
test.py: move environment preparation to one method
test.py: introduce new environment variable TESTPY_PREPARED_ENVIRONMENT
This reverts commit 1bb897c7ca, reversing
changes made to 954f2cbd2f. It makes
incompatible changes to the object storage configuration format, breaking
tests [1]. It's likely that it doesn't break any production configuration,
but we can't be sure.
Fixes#27966Closesscylladb/scylladb#27969
This changes introduces tablet size based load balancing. It is an
extension of capacity based balancing with the addition of actual tablet
sizes.
It computes the difference between the most and least loaded nodes in
the DC and stops further balancing if this difference is bellow the
config option size_based_balance_threshold_percentage.
This config option does not apply to the absolute load, but instead to
the percentage of how much the most loaded node is more loaded than the
least loaded node:
delta = (most_loaded - least_loaded) / most_loaded
If this delta is smaller then the config threshold, the balancer will
consider the nodes balanced.
To configure S3 storage, one needs to do
```
object_storage_endpoints:
- name: s3.us-east-1.amazonaws.com
port: 443
https: true
aws_region: us-east-1
```
and for GCS it's
```
object_storage_endpoints:
- name: https://storage.googleapis.com:433
type: gs
credentials_file: <gcp account credentials json file>
```
This PR updates the S3 part to look like
```
object_storage_endpoints:
- name: https://s3.us-east-1.amazonaws.com:443
aws_region: us-east-1
```
fixes: #26570
Not-yet released feature, no need to backport. Old configs are not accepted any longer. If it's needed, then this decision needs to be revised.
Closesscylladb/scylladb#27360
* github.com:scylladb/scylladb:
object_storage: Temporarily handle pure endpoint addresses as endpoints
code: Remove dangling mentions of s3::endpoint_config
docs: Update docs according to new endpoints config option format
object_storage: Create s3 client with "extended" endpoint name
test: Add named constants for test_get_object_store_endpoints endpoint names
s3/storage: Tune config updating
sstable: Shuffle args for s3_client_wrapper
This pull request introduces a new caching mechanism for client options in the Alternator and transport layers, refactors how client metadata is stored and accessed, and extends the `system.clients` virtual table to surface richer client information. The changes improve efficiency by deduplicating commonly used strings (like driver names/versions and client options), and ensure that client data is handled in a way that's safe for cross-shard access. Additionally, the test suite and virtual table schema are updated to reflect the new client options data.
**Caching and client metadata refactoring:**
* The largest and most repeatable items in the connection state before this PR were a `driver_name` and a `driver_version` which were stored as an `sstring` object which means that the corresponding memory consumption was 16 bytes per each such value at least (the smallest size of the `seastar`'s `sstring` object) **per-connection**. In reality the driver name is usually longer than 15 characters, e.g. "ScyllaDB Python Driver" is 23 characters and this is not the longest driver name there is. In such cases the actual memory usage of a corresponding `sstring` object jumps to 8 + 4 + 1 + (string length, 23 in our example) + 1.
So, for "ScyllaDB Python Driver" it would be 37 bytes (in reality it would be a bit more due to natural alignment of other allocations since the `contents` size is not well aligned (13 bytes), but let's ignore this for now).
* These bytes add up quickly as there are more connections and, sometimes we are talking about millions of connections per-shard.
* Using a smart pointer (`lw_shared_ptr`) referencing a corresponding cached value will effectively reduce the per-connection memory usage to be 8 bytes (a size of a pointer on 64-bit CPU platform) for each such value. While storing a corresponding `sstring` value only once.
* This will would reduce the "variable" (per-connection) memory usage by **at least 50%**. And in case of "ScyllaDB Python Driver" driver version - by 78%!
* And all this for a price of a single `loading_shared_values` object **per-shard** (implements a hash table) and a minor overhead for each value **stored** in it.
* Introduced a new cache type (`client_options_cache_type`) for deduplicating and sharing client option strings, and refactored `client_data`, `client_state`, and related classes to use `foreign_ptr<std::unique_ptr<client_data>>` and cached entry types for fields like driver name, driver version, and client options. (`client_data.hh`, `service/client_state.hh`, `alternator/server.hh`, `alternator/controller.hh`, `transport/controller.hh`, `transport/protocol_server.hh`) [[1]](diffhunk://#diff-664a3b19e905481bdf8eb3843fc4d34691067bb97ab11cfd6e652e74aac51d9fR33-R36) [[2]](diffhunk://#diff-664a3b19e905481bdf8eb3843fc4d34691067bb97ab11cfd6e652e74aac51d9fL40-R56) [[3]](diffhunk://#diff-daadce1a2de3667511e59558f3a8f077b5ee30a14bcc6a99d588db90d0fcd2bdL105-R107) [[4]](diffhunk://#diff-daadce1a2de3667511e59558f3a8f077b5ee30a14bcc6a99d588db90d0fcd2bdL154-R182) [[5]](diffhunk://#diff-5fce246edf5abffb2351bd02e2eb1e9850880f7a00607ccaa90c3eee7ef57c6bL91-R92) [[6]](diffhunk://#diff-5fce246edf5abffb2351bd02e2eb1e9850880f7a00607ccaa90c3eee7ef57c6bL110-R111) [[7]](diffhunk://#diff-31730ba8e7374f784a88dc27c1512291cf73b7f24e08768f7466a3c8cfcc7a1aL96-R96) [[8]](diffhunk://#diff-19a97c0247cc08155ee49b277e43859ca32d6ef8cbff0ed7368ec5fa19e0a11eL172-R172) [[9]](diffhunk://#diff-eea7e2db5d799a25e717a72ac8ce5842bd4adb72b694d38d8f47166d9cd926faL356-R356) [[10]](diffhunk://#diff-d0b4ec3a144bbc5dc993866cf0b940850a457ff6156064f7e2b4b10ad0a95fefL80-R80) [[11]](diffhunk://#diff-4293b94c444d9bd5ecd17ce7eda8c00685d35ecf6e07f844efc91a91bbe85be1L46-R48)
* Updated the methods for setting and getting driver name, driver version, and client options in `client_state` to be asynchronous and use the new cache. (`service/client_state.hh`, `service/client_state.cc`) [[1]](diffhunk://#diff-daadce1a2de3667511e59558f3a8f077b5ee30a14bcc6a99d588db90d0fcd2bdL154-R182) [[2]](diffhunk://#diff-99634aae22e2573f38b4e2f050ed2ac4f8173ff27f0ae8b3609d1f0cc1aeb775R347-R362)
**Virtual table and API enhancements:**
* Extended the `system.clients` virtual table schema and implementation to include a new `client_options` column (a map of option key/value pairs), and updated the table population logic to use the new cached types and foreign pointers. (`db/virtual_tables.cc`) [[1]](diffhunk://#diff-05f7bff3edb39fb8759c90b445e860189f2f30e04717ed58bae42716082af3d1R752) [[2]](diffhunk://#diff-05f7bff3edb39fb8759c90b445e860189f2f30e04717ed58bae42716082af3d1L769-R770) [[3]](diffhunk://#diff-05f7bff3edb39fb8759c90b445e860189f2f30e04717ed58bae42716082af3d1L809-R816) [[4]](diffhunk://#diff-05f7bff3edb39fb8759c90b445e860189f2f30e04717ed58bae42716082af3d1L828-R879)
**API and interface changes:**
* Changed the signatures of `get_client_data` methods throughout the codebase to return vectors of `foreign_ptr<std::unique_ptr<client_data>>` instead of plain `client_data` objects, to ensure safe cross-shard access. (`alternator/controller.hh`, `alternator/controller.cc`, `alternator/server.hh`, `alternator/server.cc`, `transport/controller.hh`, `transport/protocol_server.hh`) [[1]](diffhunk://#diff-31730ba8e7374f784a88dc27c1512291cf73b7f24e08768f7466a3c8cfcc7a1aL96-R96) [[2]](diffhunk://#diff-19a97c0247cc08155ee49b277e43859ca32d6ef8cbff0ed7368ec5fa19e0a11eL172-R172) [[3]](diffhunk://#diff-5fce246edf5abffb2351bd02e2eb1e9850880f7a00607ccaa90c3eee7ef57c6bL110-R111) [[4]](diffhunk://#diff-a7e2cda866c03a75afcf3b087de1c1dcd2e7aa996214db67f9a11ed6451e596dL988-R995) [[5]](diffhunk://#diff-eea7e2db5d799a25e717a72ac8ce5842bd4adb72b694d38d8f47166d9cd926faL356-R356) [[6]](diffhunk://#diff-d0b4ec3a144bbc5dc993866cf0b940850a457ff6156064f7e2b4b10ad0a95fefL80-R80) [[7]](diffhunk://#diff-4293b94c444d9bd5ecd17ce7eda8c00685d35ecf6e07f844efc91a91bbe85be1L46-R48)
**Testing and validation:**
* Updated the Python test for the `system.clients` table to verify the new `client_options` column and its contents, ensuring that driver name and version are present in the options map. (`test/cqlpy/test_virtual_tables.py`) [[1]](diffhunk://#diff-6dd8bd4a6a82cd642252a29dc70726f89a46ceefb991c3e63fc67e283f323f03R79) [[2]](diffhunk://#diff-6dd8bd4a6a82cd642252a29dc70726f89a46ceefb991c3e63fc67e283f323f03R88-R90)
Closesscylladb/scylladb#25746
* github.com:scylladb/scylladb:
transport/server: declare a new "CLIENT_OPTIONS" option as supported
service/client_state and alternator/server: use cached values for driver_name and driver_version fields
system.clients: add a client_options column
controller: update get_client_data to use foreign_ptr for client_data
This patch consists of a few smaller follow-ups to the view building worker:
- catch general execption in staging task registrator
- remove unnecessary CV broadcast
- don't pollute function context with conditionally compiled variable
- avoid creating a copy of tasks map
- fix some typos
Refs https://github.com/scylladb/scylladb/issues/25929
Refs https://github.com/scylladb/scylladb/pull/26897
This PR doesn't fix any bugs but recently we're backporting some PRs to 2025.4, so let's also backport this one to avoid painful conflicts.
Closesscylladb/scylladb#26558
* github.com:scylladb/scylladb:
docs/dev/view-building-coordinator: fix typos
db/view/view_building_worker: remove unnnecessary empty lines
db/view/view_building_worker: fix typo
db/view/view_building_worker: avoid creating a copy of tasks map
db/view/view_building_worker: wrap conditionally compiled code in a scope
db/view/view_building_worker: remove unnecessary CV broadcast
db/view/view_building_worker: catch general execption in staging task registrator
Declare support for a 'CLIENT_OPTIONS' startup key.
This key is meant to be used by drivers for sending client-specific
configurations like request timeouts values, retry policy configuration, etc.
The value of this key can be any string in general (according to the CQL binary protocol),
however, it's expected to be some structured format, e.g. JSON.
Signed-off-by: Vlad Zolotarov <vladz@scylladb.com>
Make the removenode operation go through the `left_token_ring` state,
similar to decommission. This ensures that when removenode completes,
all nodes in the cluster are aware of the topology change through a
global token metadata barrier.
Previously, removenode would skip the `left_token_ring` state and go
directly from `write_both_read_new` to `left` state. This meant that
when the operation completed, some nodes might not yet know about the
topology change, potentially causing issues with subsequent data plane
requests.
Key changes:
- Both decommission and removenode now transition to `left_token_ring`
state in the `write_both_read_new` handler
- In `left_token_ring` state, only decommissioning nodes receive the
shutdown RPC (removed nodes may already be dead)
- Updated documentation to reflect that both operations use this state
This change improves consistency guarantees for removenode operations
by ensuring cluster-wide awareness before completion.
Fixes: scylladb/scylladb#25530
Previously, the view building coordinator relied on setting each task's state to STARTED and then explicitly removing these state entries once tasks finished, before scheduling new ones. This approach induced a significant number of group0 commits, particularly in large clusters with many nodes and tablets, negatively impacting performance and scalability.
With the update, the coordinator and worker logic has been restructured to operate without maintaining per-task states. Instead, tasks are simply tracked with an aborted boolean flag, which is still essential for certain tablet operations. This change removes much of the coordination complexity, simplifies the view building code, and reduces operational overhead.
In addition, the coordinator now batches reports of finished tasks before making commits. Rather than committing task completions individually, it aggregates them and reports in groups, significantly minimizing the frequency of group0 commits. This new approach is expected to improve efficiency and scalability during materialized view construction, especially in large deployments.
Fixes https://github.com/scylladb/scylladb/issues/26311
This patch needs to be backported to 2025.4.
Closesscylladb/scylladb#26897
* github.com:scylladb/scylladb:
docs/dev/view-building-coordinator: update the docs after recent changes
db/view/view_building: send coordinator's term in the RPC
db/view/view_building_state: replace task's state with `aborted` flag
db/view/view_building_coordinator: batch finished tasks reporting
db/view/view_building_worker: change internal implementation
db/view/view_building_coordinator: change `work_on_tasks` RPC return type
When migrating tablet size during the end_migration tablet transition stage, we need the pending and leaving replica hosts. The leaving and pending replicas are gathered in objects of type std::optional<tablet_replica> and are not checked if they contain a value before dereferencing which could cause an exception in the topology coordinator.
This patch adds a check for leaving and pending replicas, and only performs the tablet size migration if neither are empty.
This bug was introduced in 10f07fb95a
This change also adds the ability to create a tablet size in load_stats during end_migration stage of a tablet rebuild. We compute the new tablet size from by averaging the tablet sizes of the existing replicas.
This change also adds the virtual table tablet_sizes which contains tablet sizes of all the replicas of all the tablets in the cluster.
A version containing this bug has not yet been released, so a backport is not needed.
Closesscylladb/scylladb#27118
* github.com:scylladb/scylladb:
test: add tests for tablet size migration during end_migration
virtual_table: add tablet_sizes virtual table
load_stats: update tablet sizes after migration or rebuild
