commit 7c8c020 introduced a new type of a keyspace, an internal keyspace
It defined the semantics for this internal keyspace, this keyspace is
somewhat a hybrid between system and user keyspace.
Here we extend the semantics to include also flushes, meaning that
flushes will be done using the system dirty_mamory_manager. This is
in order to allow inter dependencies between internal tables and user
tables and prevent deadlocks.
One example of such a deadlock is our `replicated_key_provider`
encryption on the enterprise version. The deadlock occur because in some
circumstances, an encrypted user table flush is dependant upon the
`encrypted_keys` table being flushed but since the requests are
serialized, we get a deadlock.
Tests: unit tests dev + debug
The deadlock dtest reproducer:
encryption_at_rest_test.py::TestEncryptionAtRest::test_reboot
Fixes#14529
Signed-off-by: Eliran Sinvani <eliransin@scylladb.com>
Closes#14547
The option was introduced to bootstrap the project. It's still
useful for testing, but that translates into maintaining an
additional option and code that will not be really used
outside of testing. A possible option is to later map the
option in boost tests to initial_tablets, which may yield
the same effect for testing.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
The dependency is needed by db::schema_tables to get wasm manager for
its needs. This patch prepares the ground. Now the wasm::manager is
shared between replica::database and cql3::query_processor
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
If some state update in database::add_column_family throws,
info about a column family would be inconsistent.
Undo already performed operations in database::add_column_family
when one throws.
Fixes: #14666.
Closes#14672
* github.com:scylladb/scylladb:
replica: undo the changes if something fails
replica: start table earlier in database::add_column_family
By default, per-table-per-shard metrics reporting is turned off, and the
aggregated version of the metrics (per-table-per-node) will be turned
on.
There could be a situation where a user with an excessive number of
tables would suffer from performance issues, both from the network and
the metrics collection server.
This patch adds a config option, enable_node_table_metrics, which allows
users to turn off per-table metrics reporting altogether.
For example, when running Scylla with the command line argument
'--enable-node-aggregated-table_metrics 0' per-table metrics will not be reported.
Signed-off-by: Amnon Heiman <amnon@scylladb.com>
Maps related to column families in database are extracted
to a column_families_data class. Access to them is possible only
through methods. All methods which may preempt hold rwlock
in relevant mode, so that the iterators can't become invalid.
Fixes: #13290Closes#13349
* github.com:scylladb/scylladb:
replica: make tables_metadata's attributes private
replica: add methods to get a filtered copy of tables map
replica: add methods to check if given table exists
replica: add methods to get table or table id
replica: api: return table_id instead of const table_id&
replica: iterate safely over tables related maps
replica: pass tables_metadata to phased_barrier_top_10_counts
replica: add methods to safely add and remove table
replica: wrap column families related maps into tables_metadata
replica: futurize database::add_column_family and database::remove
There are three methods in system_keyspace namespace that run queries over `system.scylla_table_schema_history` table. For that they use qctx which's not nice.
Fortunately, all the callers already have the system_keyspace& local variable or argument they can pass to those methods. Since the accessed table belongs to system keyspace, the latter declares the querying methods as "friends" to let them get private `query_processor& _qp` member
Closes#14876
* github.com:scylladb/scylladb:
schema_tables: Extract query_processor from system_keyspace for querying
schema_tables: Add system_keyspace& argument to ..._column_mapping() calls
migration_manager: Add system_keyspace argument to get_schema_mapping()
The callers all have local sys_ks argument:
- merge_tables_and_views()
- service::get_column_mapping()
- database::parse_system_tables()
And a test that can get it from cql_test_env.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Now that all users have opted in unconditionally, there is no point in
keeping this optional. Make it mandatory to make sure there are no
opt-out by mistake.
The global override via enable_compacting_data_for_streaming_and_repair
config item still remains, allowing compaction to be force turned-off.
Doing to make_multishard_streaming_reader() what the previous commit did
to make_streaming_reader(). In fact, the new compaction_time parameter
is simply forwarded to the make_streaming_reader() on the shard readers.
Call sites are updated, but none opt in just yet.
Opt-in is possible by passing an engaged `compaction_time`
(gc_clock::time_point) to the method. When this new parameter is
disengaged, no compaction happens.
Note that there is a global override, via the
enable_compacting_data_for_streaming_and_repair config item, which can
force-disable this compaction.
Compaction done on the output of the streaming reader does *not*
garbage-collect tombstones!
All call-sites are adjusted (the new parameter is not defaulted), but
none opt in yet. This will be done in separate commit per user.
After this series, tablet replication can handle the scenario of bootstrapping new nodes. The ownership is distributed indirectly by the means of a load-balancer which moves tablets around in the background. See docs/dev/topology-over-raft.md for details.
The implementation is by no means meant to be perfect, especially in terms of performance, and will be improved incrementally.
The load balancer will be also kicked by schema changes, so that allocation/deallocation done during table creation/drop will be rebalanced.
Tablet data is streamed using existing `range_streamer`, which is the infrastructure for "the old streaming". This will be later replaced by sstable transfer once integration of tablets with compaction groups is finished. Also, cleanup is not wired yet, also blocked by compaction group integration.
Closes#14601
* github.com:scylladb/scylladb:
tests: test_tablets: Add test for bootstraping a node
storage_service: topology_coordinator: Implement tablet migration state machine
tablets: Introduce tablet_mutation_builder
service: tablet_allocator: Introduce tablet load balancer
tablets: Introduce tablet_map::for_each_tablet()
topology: Introduce get_node()
token_metadata: Add non-const getter of tablet_metadata
storage_service: Notify topology state machine after applying schema change
storage_service: Implement stream_tablet RPC
tablets: Introduce global_tablet_id
stream_transfer_task, multishard_writer: Work with table sharder
tablets: Turn tablet_id into a struct
db: Do not create per-keyspace erm for tablet-based tables
tablets: effective_replication_map: Take transition stage into account when computing replicas
tablets: Store "stage" in transition info
doc: Document tablet migration state machine and load balancer
locator: erm: Make get_endpoints_for_reading() always return read replicas
storage_service: topology_coordinator: Sleep on failure between retries
storage_service: topology_coordinator: Simplify coordinator loop
main: Require experimental raft to enable tablets
The method is called by db::truncate_table_on_all_shards(), its call-chain, in turn, starts from
- proxy::remote::handle_truncate()
- schema_tables::merge_schema()
- legacy_schema_migrator
- tests
All of the above are easy to get system_keyspace reference from. This, in turn, allows making the method non-static and use query_processor reference from system_keyspace object in stead of global qctx
Closes#14778
* github.com:scylladb/scylladb:
system_keyspace: Make save_truncation_record() non-static
code: Pass sharded<db::system_keyspace>& to database::truncate()
db: Add sharded<system_keyspace>& to legacy_schema_migrator
This erm is not updated when replicating token metadata in
storage_service::replicate_to_all_cores() so will pin token metadata
version and prevent token metadata barrier from finishing.
It is not necessary to have per-keyspace erm for tablet-based tables,
so just don't create it.
As a preparation for ensuring access safety for column families
related maps, add tables_metadata, access to members of which
would be protected by rwlock.
If semaphore mismatch occurs, check whether both semaphores belong
to user. If so, log a warning, log a `querier_cache_scheduling_group_mismatches` stat and drop cached reader instead of throwing an error.
Until now, semaphore mismatch was only checked in multi-partition queries. The PR pushes the check to `querier_cache` and perform it on all `lookup_*_querier` methods.
The mismatch can happen if user's scheduling group changed during
a query. We don't want to throw an error then, but drop and reset
cached reader.
This patch doesn't solve a problem with mismatched semaphores because of changes in service levels/scheduling groups but only mitigate it.
Refers: https://github.com/scylladb/scylla-enterprise/issues/3182
Refers: https://github.com/scylladb/scylla-enterprise/issues/3050Closes: #14770Closes#14736
* github.com:scylladb/scylladb:
querier_cache: add stats of scheduling group mismatches
querier_cache: check semaphore mismatch during querier lookup
querier_cache: add reference to `replica::database::is_user_semaphore()`
replica:database: add method to determine if semaphore is user one
Fixes#14668
In #14668, we have decided to introduce a new `scylla.yaml` variable for the schema commitlog segment size and set it to 128MB. The reason is that segment size puts a limit on the mutation size that can be written at once, and some schema mutation writes are much larger than average, as shown in #13864. This `schema_commitlog_segment_size_in_mb variable` variable is now added to `scylla.yaml` and `db/config`.
Additionally, we do not derive the commitlog sync period for schema commitlog anymore because schema commitlog runs in batch mode, so it doesn't need this parameter. It has also been discussed in #14668.
Closes#14704
* github.com:scylladb/scylladb:
replica: do not derive the commitlog sync period for schema commitlog
config: set schema_commitlog_segment_size_in_mb to 128
config: add schema_commitlog_segment_size_in_mb variable
Previously semaphore mismatch was checked only in multi-partition
queries and if happened, an internal error was thrown.
This commit pushed the check down to `querier_cache`, so each
`lookup_*_querier` method will check for the mismatch.
What's more, if semaphore mismatch occurs, check whether both semaphores belong
to user. If so, log a warning and drop cached reader instead of
throwing an error.
The mismatch can happen if user's scheduling group changed during
a query. We don't want to throw an error then, but drop and reset
cached reader.
The arguments goes via the db::(drop|truncate)_table_on_all_shards()
pair of calls that start from
- storage_proxy::remote: has its sys.ks reference already
- schema_tables::merge_schema: has sys.ks argument already
- legacy_schema_migrator: the reference was added by previous patch
- tests: run in cql_test_env with sys.ks on board
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
We don't want to apply the value of the commitlog_sync_period_in_ms
variable to schema commitlog. Schema commitlog runs in batch mode,
so it doesn't need this parameter.
In #14668, we have decided to introduce a new scylla.yaml variable
for the schema commitlog segment size. The segment size puts a limit
on the mutation size that can be written at once, and some schema
mutation writes are much larger than average, as shown in #13864.
Therefore, increasing the schema commitlog segment size is sometimes
necessary.
Now it sits in replicate/database.cc, but the latter is overloaded with
code, worth keeping less, all the more so the ..._prefix itself lives in
the keys.hh header.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closes#14748
We add an overload of make_multishard_streaming_reader
which reads all the data in the given range. We will use it later
in row level repair if --smp is different on the
nodes and the number of partitions is small.
We are going to use it later in a new
make_multishard_streaming_reader overload.
In this commit we just move it outside
into the anonymous namespace, no other code changes
were made.
When creating or altering a keyspace, we create a new
effective_replication_map instance.
It is more efficient to do that first on shard 0
and then on all other shards, otherwise multiple
shards might need to calculate to new e_r_m (and reach
the same result). When the new e_r_m is "seeded" on
shard 0, other shards will find it there and clone
a local copy of it - which is more efficient.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
When creating, updating, or dropping keyspaces,
first execute the database internal function to
modify the database state, and only when all shards
are updated, run the listener notifications,
to make sure they would operate when the database
shards are consistent with each other.
Fixes#13137
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Run all keyspace create/update/drop ops
via `modify_keyspace_on_all_shards` that
will standardize the execution on all shards
in the coming patches.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Similar to create_keyspace_on_all_shards,
`extract_scylla_specific_keyspace_info` and
`create_keyspace_from_schema_partition` can be called
once in the upper layer, passing keyspace_metadata&
down to database::update_keyspace_on_all_shards
which now would only make the per-shard
keyspace_metadata from the reference it gets
from the schema_tables layer.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Part of moving the responsibility for applying
and notifying keyspace schema changes from
schema_tables to the database so that the
database can control the order of applying the changes
across shards and when to notify its listeners.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Part of moving the responsibility for applying
and notifying keyspace schema changes from
schema_tables to the database so that the
database can control the order of applying the changes
across shards and when to notify its listeners.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Part of moving the responsibility for applying
and notifying keyspace schema changes from
schema_tables to the database so that the
database can control the order of applying the changes
across shards and when to notify its listeners.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
dht::shard_of() does not use the correct sharder for tablet-based tables.
Code which is supposed to work with all kinds of tables should use erm::get_sharder().
Currently, the coordinator splits the partition range at vnode (or
tablet) boundaries and then tries to merge adjacent ranges which
target the same replica. This is an optimization which makes less
sense with tablets, which are supposed to be of substantial size. If
we don't merge the ranges, then with tablets we can avoid using the
multishard reader on the replica side, since each tablet lives on a
single shard.
The main reason to avoid a multishard reader is avoiding its
complexity, and avoiding adapting it to work with tablet
sharding. Currently, the multishard reader implementation makes
several assumptions about shard assignment which do not hold with
tablets. It assumes that shards are assigned in a round-robin fashion.
