The PRUNE MATERALIZED VIEW statement is performed as follows:
1. Perform a range scan of the view table from the view replicas based
on the ranges specified in the statement.
2. While reading the paged scan above, for each view row perform a read
from all base replicas at the corresponding primary key. If a discrepancy
is detected, delete the row in the view table.
When reading multiple rows, this is very slow because for each view row
we need to performe a single row query on multiple replicas.
In this patch we add an option to speed this up by performing many of the
single base row reads concurrently, at the concurrency specified in the
USING CONCURRENCY clause.
Aside from the unit test, I checked manually on a 3-node cluster with 10M rows, using vnodes. There were actually no ghost rows in the test, but we still had to iterate over all view rows and read the corresponding base rows. And actual ghost rows, if there are any, should be a tiny fraction of all rows. I compared concurrencies 1,2,10,100 and the results were:
* Pruning with concurrency 1 took total 1416 seconds
* Pruning with concurrency 2 took total 731 seconds
* Pruning with concurrency 10 took total 234 seconds
* Pruning with concurrency 100 took total 171 seconds
So after a concurrency of 10 or so we're hitting diminishing returns (at least in this setup). At that point we may be no longer bottlenecked by the reads, but by CPU on the shard that's handling the PRUNE
Fixes https://github.com/scylladb/scylladb/issues/27070Closesscylladb/scylladb#27097
* github.com:scylladb/scylladb:
mv: allow setting concurrency in PRUNE MATERIALIZED VIEW
cql: add CONCURRENCY to the USING clause
This commit removes the now redundant driver pages from
the Scylla DB documentation. Instead, the link to the pages
where we moved the diver information is added.
Also, the links are updated across the ScyllaDB manual.
Redirections are added for all the removed pages.
Fixes https://github.com/scylladb/scylladb/issues/26871Closesscylladb/scylladb#27277
The metrics extension now includes validation to detect missing metrics. This validation caused failures during multiversion publication because older versions did not generate all required properties.
Instead of fixing each branch, a strict mode flag was introduced to control when validation should run.
Strict mode is enabled in the workflow that validates pull requests, ensuring that new changes meet the expected metrics.
During multiversion builds, validation errors are now logged but do not raise exceptions, which prevents build failures while still providing visibility into missing data.
docs: verbose mode
docs: verbose mode
Closesscylladb/scylladb#27402
The PRUNE MATERALIZED VIEW statement is performed as follows:
1. Perform a range scan of the view table from the view replicas based
on the ranges specified in the statement.
2. While reading the paged scan above, for each view row perform a read
from all base replicas at the corresponding primary key. If a discrepancy
is detected, delete the row in the view table.
When reading multiple rows, this is very slow because for each view row
we need to performe a single row query on multiple replicas.
In this patch we add an option to speed this up by performing many of the
single base row reads concurrently, at the concurrency specified in the
USING CONCURRENCY clause.
Fixes https://github.com/scylladb/scylladb/issues/27070
A new feature was announced this week for Amazon DynamoDB, "multi-
attribute composite keys in global secondary indexes", which allows to
create GSIs with composite keys (multiple columns). This feature already
existed in CQL's materialized views, but didn't exist in DynamoDB until
now.
So this patch adds a paragraph to our docs/alternator/compatibility.md
mentioning that we don't support this DynamoDB feature yet.
See also issue #27182 which we opened to track this unimplemented
feature.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closesscylladb/scylladb#27183
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
There is a limited number of ways to obtain the schema of a table:
1) Use DESCRIBE TABLE in cqlsh
2) Find the schema definition in the code (for system tables)
3) Ask support/user to provide schema
4) Piece together the schema definition from the system tables
Option (1) is the most convenient but requires access to live cluster.
(2) is limited to system tables only.
When investigating issues for customers, we have to rely on (3) and this
often adds communication round-trips and delays. (4) requires knowledge
of ScyllaDB internals and access to system tables.
The new dump-schema commands provides a convenient way to obtain the
schema of tables, given that there is access to either an sstable or the
system tables. It can dump the schema of system tables without either.
Closesscylladb/scylladb#26433
fix: windows gitbash support
fix: new name found with no group vector_search/vector_store_client.cc 343
fix: rm allowmismatch
fix: git bash (windows) compatibility
fix: git bash (windows) compatibility
Closesscylladb/scylladb#26173
To support debian13, we need to modify the installation instructions since `apt-key` command is no longer available
Also updated installation instruction to match the latest release
Fixes: https://github.com/scylladb/scylladb/issues/26673
**No need for backport since we added debian13 only in master for now**
Closesscylladb/scylladb#27205
* github.com:scylladb/scylladb:
install-on-linux.rst: update installation example to supported release
docs: modify debian/ubutnu installation instructions
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
Example of installation is out of date, since scylla-5.2 is EOL for long time
upding the example for more recent release (together with packages update)
This commit fixes the information about object storage:
- Object storage configuration is no longer marked as experimental.
- Redundant information has been removed from the description.
- Information related to object storage for SStabels has been removed
as the feature is not working.
Fixes https://github.com/scylladb/scylladb/issues/26985Closesscylladb/scylladb#26987
This PR:
- Removes n1-highmem instances from Recommended Instances.
- Adds missing support for n2-highmem-96.
- Updates the reference to n2 instances in the Google Cloud docs (fixes a broken link to GCP).
- Adds the missing information about processors for n2-highmem-instance - Ice Lake and Cascade Lake (requested by CX).
Fixes https://github.com/scylladb/scylladb/issues/25946
Fixes https://github.com/scylladb/scylladb/issues/24223
Fixes https://github.com/scylladb/scylladb/issues/23976
No backport needed if this PR is merged before 2025.4 branching.
Closesscylladb/scylladb#26182
* github.com:scylladb/scylladb:
doc: update information for n2-highmem instances
doc: remove n1-highmem instances from Recommended Instances
This commit updates the section for n2-highmem instances
on the Cloud Instance Recommendations page
- Added missing support for n2-highmem-96
- Update the reference to n2 instances in the Google Cloud docs.
- Added the missing information about processors for this instance
type (Ice Lake and Cascade Lake).
Add documentation for the quarantine/ subdirectory that holds SSTables
isolated due to validation failures or corruption. Document the scrub
operation's quarantine_mode parameter options and the drop_quarantined_sstables
API operation.
Also update the directory hierarchy example to include the quarantine directory.
Fixes#10742
Signed-off-by: Shreyas Ganesh <vansi.ganeshs@gmail.com>
Closesscylladb/scylladb#27023
Add a table name to Alternator's tracing output, as some clients would
like to consistently receive this information.
- add missing `tracing::add_table_name` in `executor::scan`
- add emiting tables' names in `trace_state::build_parameters_map`
- update tests, so when tracing is looked for it is filtered by table's
name, which confirms table is being outputed.
- change `struct one_session_records` declaration to `class one_session_records`,
as `one_session_records` is later defined as class.
Refs #26618Fixes#24031Closesscylladb/scylladb#26634
Adds a new documentation page for the incremental repair feature.
The page covers:
- What incremental repair is and its benefits over the standard repair process.
- How it works at a high level by tracking the repair status of SSTables.
- The prerequisite of using the tablets architecture.
- The different user-configurable modes: 'regular', 'full', and 'disabled'.
Fixes#25600Closesscylladb/scylladb#26221
Fixes#27077
Multiple points can be clarified relating to:
* Names of each sub-procedure could be clearer
* Requirements of each sub-procedure could be clearer
* Clarify which keyspaces are relevant and how to check them
* Fix typos in keyspace name
Closesscylladb/scylladb#26855
Update nodetool scrub documentation to include --quarantine-mode and --drop-unfixable-sstables options,
add a section explaining quarantine modes
and provide examples and procedures for handling and removing corrupted SSTables.
Closesscylladb/scylladb#27018
This patch adds the missing warning about the lack of possibility
to return the similarity distance. This will be added in the next
iteration.
Fixes#27086
It has to be backported to 2025.4 as this is the limitation in 2025.4.
Closesscylladb/scylladb#27096
The updates include:
- adding missing parts like topology states and table rows,
- documenting zero-token nodes,
- replacing the old recovery procedure with the new one.
Fixes#26412
Updates of internal docs (usually read on master) don't require
backporting.
Closesscylladb/scylladb#27022
* github.com:scylladb/scylladb:
docs/dev/topology-over-raft: update the recovery section
docs/dev/topology-over-raft: document zero-token nodes
docs/dev/topology-over-raft: clarify the lack of tablet-specific states
docs/dev/topology-over-raft: add the missing join_group0 state
docs/dev/topology-over-raft: update the topology columns
This series allows an operator to reset 'cleanup needed' flag if he already cleaned up the node, so that automatic cleanup will not do it again. We also change 'nodetool cleanup' back to run cleanup on one node only (and reset 'cleanup needed' flag in the end), but the new '--global' option allows to run cleanup on all nodes that needed it simultaneously.
Fixes https://github.com/scylladb/scylladb/issues/26866
Backport to all supported version since automatic cleanup behaviour as it is now may create unexpected by the operator load during cluster resizing.
Closesscylladb/scylladb#26868
* https://github.com/scylladb/scylladb:
cleanup: introduce "nodetool cluster cleanup" command to run cleanup on all dirty nodes in the cluster
cleanup: Add RESTful API to allow reset cleanup needed flag
97ab3f6622 changed "nodetool cleanup" (without arguments) to run
cleanup on all dirty nodes in the cluster. This was somewhat unexpected,
so this patch changes it back to run cleanup on the target node only (and
reset "cleanup needed" flag afterwards) and it adds "nodetool cluster
cleanup" command that runs the cleanup on all dirty nodes in the
cluster.
Some of the columns were added, but the doc wasn't updated.
`upgrade_state` was updated in only one of the two places.
`ignore_nodes` was changed to a static column.
The service level controller relies on `auth::service` to collect
information about roles and the relation between them and the service
levels (those attached to them). Unfortunately, the service level
controller is initialized way earlier than `auth::service` and so we
had to prevent potential invalid queries of user service levels
(cf. 46193f5e79).
Unfortunately, that came at a price: it made the maintenance socket
incompatible with the current implementation of the service level
controller. The maintenance socket starts early, before the
`auth::service` is fully initialized and registered, and is exposed
almost immediately. If the user attempts to connect to Scylla within
this time window, via the maintenance socket, one of the things that
will happen is choosing the right service level for the connection.
Since the `auth::service` is not registered, Scylla with fail an
assertion and crash.
A similar scenario occurs when using maintenance mode. The maintenance
socket is how the user communicates with the database, and we're not
prepared for that either.
To avoid unnecessary crashes, we add new branches if the passed user is
absent or if it corresponds to the anonymous role. Since the role
corresponding to a connection via the maintenance socket is the anonymous
role, that solves the problem.
Some accesses to `auth::service` are not affected and we do not modify
those.
Fixesscylladb/scylladb#26816
Backport: yes. This is a fix of a regression.
Closesscylladb/scylladb#26856
* github.com:scylladb/scylladb:
test/cluster/test_maintenance_mode.py: Wait for initialization
test: Disable maintenance mode correctly in test_maintenance_mode.py
test: Fix keyspace in test_maintenance_mode.py
service/qos: Do not crash Scylla if auth_integration absent
This patch series re-enables support for speculative retry values `0` and `100`. These values have been supported some time ago, before [schema: fix issue 21825: add validation for PERCENTILE values in speculative_retry configuration. #21879
](https://github.com/scylladb/scylladb/pull/21879). When that PR prevented using invalid `101PERCENTILE` values, valid `100PERCENTILE` and `0PERCENTILE` value were prevented too.
Reproduction steps from [[Bug]: drop schema and all tables after apply speculative_retry = '99.99PERCENTILE' #26369](https://github.com/scylladb/scylladb/issues/26369) are unable to reproduce the issue after the fix. A test is added to make sure the inclusive border values `0` and `100` are supported.
Documentation is updated to give more information to the users. It now states that these border values are inclusive, and also that the precision, with automatic rounding, is 1 decimal digit.
Fixes#26369
This is a bug fix. If at any time a client tries to use value >= 99.5 and < 100, the raft error will happen. Backport is needed. The code which introduced inconsistency is introduced in 2025.2, so no backporting to 2025.1.
Closesscylladb/scylladb#26909
* github.com:scylladb/scylladb:
test: cqlpy: add test case for non-numeric PERCENTILE value
schema: speculative_retry: update exception type for sstring ops
docs: cql: ddl.rst: update speculative-retry-options
test: cqlpy: add test for valid speculative_retry values
schema: speculative_retry: allow 0 and 100 PERCENTILE values
This PR extends the restore API so that it accepts primary_replica_only as parameter and it combines the concepts of primary-replica-only with scoped streaming so that with:
- `scope=all primary_replica_only=true` The restoring node will stream to the global primary replica only
- `scope=dc primary_replica_only=true` The restoring node will stream to the local primary replica only.
- `scope=rack primary_replica_only=true` The restoring node will stream only to the primary replica from within its own rack (with rf=#racks, the restoring node will stream only to itself)
- `scope=node primary_replica_only=true` is not allowed, the restoring node will always stream only to itself so the primary_replica_only parameter wouldn't make sense.
The PR also adjusts the `nodetool refresh` restriction on running restore with both primary_replica_only and scope, it adds primary_replica_only to `nodetool restore` and it adds cluster tests for primary replica within scope.
Fixes#26584Closesscylladb/scylladb#26609
* github.com:scylladb/scylladb:
Add cluster tests for checking scoped primary_replica_only streaming
Improve choice distribution for primary replica
Refactor cluster/object_store/test_backup
nodetool restore: add primary-replica-only option
nodetool refresh: Enable scope={all,dc,rack} with primary_replica_only
Enable scoped primary replica only streaming
Support primary_replica_only for native restore API
Before this series, Alternator's CreateTable operation defaults to creating a table replicated with vnodes, not tablets. The reasons for this default included missing support for LWT, Materialized Views, Alternator TTL and Alternator Streams if tablets are used. But today, all of these (except the still-experimental Alternator Streams) are now fully available with tablets, so we are finally ready to switch Alternator to use tablets by default in new tables.
We will use the same configuration parameter that CQL uses, tablets_mode_for_new_keyspaces, to determine whether new keyspaces use tablets by default. If set to `enabled`, tablets are used by default on new tables. If set to `disabled`, tablets will not be used by default (i.e., vnodes will be used, as before). A third value, `enforced` is similar to `enabled` but forbids overriding the default to vnodes when creating a table.
As before, the user can set a tag during the CreateTable operation to override the default choice of tablets or vnodes (unless in `enforced` mode). This tag is now named `system:initial_tablets` - whereas before this patch it was called `experimental:initial_tablets`. The rules stay the same as with the earlier, experimental:initial_tablets tag: when supplied with a numeric value, the table will use tablets. When supplied with something else (like a string "none"), the table will use vnodes.
Fixes https://github.com/scylladb/scylladb/issues/22463
Backport to 2025.4, it's important not to delay phasing out vnodes.
Closesscylladb/scylladb#26836
* github.com:scylladb/scylladb:
test,alternator: use 3-rack clusters in tests
alternator: improve error in tablets_mode_for_new_keyspaces=enforced
config: make tablets_mode_for_new_keyspaces live-updatable
alternator: improve comment about non-hidden system tags
alternator: Fix test_ttl_expiration_streams()
alternator: Fix test_scan_paging_missing_limit()
alternator: Don't require vnodes for TTL tests
alternator: Remove obsolete test from test_table.py
alternator: Fix tag name to request vnodes
alternator: Fix test name clash in test_tablets.py
alternator: test_tablets.py handles new policy reg. tablets
alternator: Update doc regarding tablets support
alternator: Support `tablets_mode_for_new_keyspaces` config flag
Fix incorrect hint for tablets_mode_for_new_keyspaces
Fix comment for tablets_mode_for_new_keyspaces
Add --primary-replica-only and update docs page for
nodetool restore.
The relationship with the scope parameter is:
- scope=all primary_replica_only=true gets the global primary replica
- scope=dc primary_replica_only=true gets the local primary replica
- scope=rack primary_replica_only=true is like a noop, it gets the only
replica in the rack (rf=#racks)
- scope=node primary_replica_only=node is not allowed
Fixes#26584
Signed-off-by: Robert Bindar <robert.bindar@scylladb.com>
