Now when the system.sstables has the state field, it can be changed
(UPDATEd). However, when changing the state AND generation, this still
won't work, because generation is the clustering key of the table in
question and cannot be just changed. This, nonetheless, is OK, as
generation changes with state only when moving an sstable from upload
dir into normal/staging and this is separate issue for S3 (#13018). For
now changing state only is OK.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The state is one of <empty>(normal)/staging/quarantine. Currently when
sstable is moved to non-normal state the s3 backend state_change() call
throws thus such sstables do not appear. Next patches are going to
change that and the new field in the system.sstables is needed.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
since we use the sstable.generation() for the remote prefix of
the key of the object for storing the sstable component, there is
no need to set remote_prefix beforehand.
since `s3_storage::ensure_remote_prefix()` and
`system_kesypace::sstables_registry_lookup_entry()` are not used
anymore, they are removed.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
before this change, we create a new UUID for a new sstable managed
by the s3_storage, and we use the string representation of UUID
defined by RFC4122 like "0aa490de-7a85-46e2-8f90-38b8f496d53b" for
naming the objects stored on s3_storage. but this representation is
not what we are using for storing sstables on local filesystem when
the option of "uuid_sstable_identifiers_enabled" is enabled. instead,
we are using a base36-based representation which is shorter.
to be consistent with the naming of the sstables created for local
filesystem, and more importantly, to simplify the interaction between
the local copy of sstables and those stored on object storage, we should
use the same string representation of the sstable identifier.
so, in this change:
1. instead of creating a new UUID, just reuse the generation of the
sstable for the object's key.
2. do not store the uuid in the sstable_registry system table. As
we already have the generation of the sstable for the same purpose.
3. switch the sstable identifier representation from the one defined
by the RFC4122 (implemented by fmt::formatter<utils::UUID>) to the
base36-based one (implemented by
fmt::formatter<sstables::generation_type>)
4. enable the `uuid_sstable_identifers` cluster feature if it is
enabled in the `test_env_config`, so that it the sstable manager
can enable the uuid-based uuid when creating a new uuid for
sstable.
5. throw if the generation of sstable is not UUID-based when
accessing / manipulating an sstable with S3 storage backend. as
the S3 storage backend now relies on this option. as, otherwise
we'd have sstables with key like s3://bucket/number/basename, which
is just unable to serve as a unique id for sstable if the bucket is
shared across multiple tables.
Fixes#14175
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Once we've started clean, and all replaying is done, truncation logs
commit log regarding replay positions are invalid. We should exorcise
them as soon as possible. Note that we cannot remove truncation data
completely though, since the time stamps stored are used by things like
batch log to determine if it should use or discard old batch data.
This PR contains several refactoring, related to truncation records handling in `system_keyspace`, `commitlog_replayer` and `table` clases:
* drop map_reduce from `commitlog_replayer`, it's sufficient to load truncation records from the null shard;
* add a check that `table::_truncated_at` is properly initialized before it's accessed;
* move its initialization after `init_non_system_keyspaces`
Closesscylladb/scylladb#15583
* github.com:scylladb/scylladb:
system_keyspace: drop truncation_record
system_keyspace: remove get_truncated_at method
table: get_truncation_time: check _truncated_at is initialized
database: add_column_family: initialize truncation_time for new tables
database: add_column_family: rename readonly parameter to is_new
system_keyspace: move load_truncation_times into distributed_loader::populate_keyspace
commitlog_replayer: refactor commitlog_replayer::impl::init
system_keyspace: drop redundant typedef
system_keyspace: drop redundant save_truncation_record overload
table: rename cache_truncation_record -> set_truncation_time
system_keyspace: get_truncated_position -> get_truncated_positions
The only usage is in batchlog_manager, and it
can be replaced with cf.get_truncation_time().
std::optional<std::reference_wrapper<canonical_mutation>>
is replaced with canonical_mutation* since it is
semantically the same but with less type boilerplate.
load_truncation_times() now works only for
schema tables since the rest is not loaded
until distributed_loader::init_non_system_keyspaces.
An attempt to call cf.set_truncation_time
for non-system table just throws an exception,
which is caught and logged with debug level.
This means that the call cf.get_truncation_time in
paxos_state.cc has never worked as expected.
To fix that we move load_truncation_times()
closer to the point where the tables are loaded.
The function distributed_loader::populate_keyspace is
called for both system and non-system tables. Once
the tables are loaded, we use the 'truncated' table
to initialize _truncated_at field for them.
The truncation_time check for schema tables is also moved
into populate_keyspace since is seems like a more natural
place for it.
This is a refactoring commit without observable
changes in behaviour.
There is a truncation_record struct, but in this method we
only care about time, so rename it (and other related methods)
appropriately to avoid confusion.
When performing a schema change through group 0, extend the schema mutations with a version that's persisted and then used by the nodes in the cluster in place of the old schema digest, which becomes horribly slow as we perform more and more schema changes (#7620).
If the change is a table create or alter, also extend the mutations with a version for this table to be used for `schema::version()`s instead of having each node calculate a hash which is susceptible to bugs (#13957).
When performing a schema change in Raft RECOVERY mode we also extend schema mutations which forces nodes to revert to the old way of calculating schema versions when necessary.
We can only introduce these extensions if all of the cluster understands them, so protect this code by a new cluster/schema feature, `GROUP0_SCHEMA_VERSIONING`.
Fixes: #7620Fixes: #13957Closesscylladb/scylladb#15331
* github.com:scylladb/scylladb:
test: add test for group 0 schema versioning
test/pylib: log_browsing: fix type hint
feature_service: enable `GROUP0_SCHEMA_VERSIONING` in Raft mode
schema_tables: don't delete `version` cell from `scylla_tables` mutations from group 0
migration_manager: add `committed_by_group0` flag to `system.scylla_tables` mutations
schema_tables: use schema version from group 0 if present
migration_manager: store `group0_schema_version` in `scylla_local` during schema changes
migration_manager: migration_request handler: assume `canonical_mutation` support
system_keyspace: make `get/set_scylla_local_param` public
feature_service: add `GROUP0_SCHEMA_VERSIONING` feature
schema_tables: refactor `scylla_tables(schema_features)`
migration_manager: add `std::move` to avoid a copy
schema_tables: remove default value for `reload` in `merge_schema`
schema_tables: pass `reload` flag when calling `merge_schema` cross-shard
system_keyspace: fix outdated comment
We add garbage collection for the `CDC_GENERATIONS_V3` table to prevent
it from endlessly growing. This mechanism is especially needed because
we send the entire contents of `CDC_GENERATIONS_V3` as a part of the
group 0 snapshot.
The solution is to keep a clean-up candidate, which is one of the
already published CDC generations. The CDC generation publisher
introduced in #15281 continually uses this candidate to remove all
generations with timestamps not exceeding the candidate's and sets a new
candidate when needed.
We also add `test_cdc_generation_clearing.py` that verifies this new
mechanism.
Fixes#15323Closesscylladb/scylladb#15413
* github.com:scylladb/scylladb:
test: add test_cdc_generation_clearing
raft topology: remove obsolete CDC generations
raft topology: set CDC generation clean-up candidate
topology_coordinator: refactor publish_oldest_cdc_generation
system_keyspace: introduce decode_cdc_generation_id
system_keyspace: add cleanup_candidate to CDC_GENERATIONS_V3
We extend schema mutations with an additional mutation to the
`system.scylla_local` table which:
- in Raft mode, stores a UUID under the `group0_schema_version` key.
- outside Raft mode, stores a tombstone under that key.
As we will see in later commits, nodes will use this after applying
schema mutations. If the key is absent or has a tombstone, they'll
calculate the global schema digest on their own -- using the old way. If
the key is present, they'll take the schema version from there.
The Raft-mode schema version is equal to the group 0 state ID of this
schema command.
The tombstone is necessary for the case of performing a schema change in
RECOVERY mode. It will force a revert to the old digest-based way.
Note that extending schema mutations with a `system.scylla_local`
mutation is possible thanks to earlier commits which moved
`system.scylla_local` to schema commitlog, so all mutations in the
schema mutations vector still go to the same commitlog domain.
We want to use the clean-up candidates to remove the obsolete CDC
generation data, but first, we need to set suitable generations as
a candidate when there is no candidate. Since CDC generations must
be published before we remove them, a generation that is being
published is a good candidate.
We remove flush from set_scylla_local_param_as
since it's now redundant. We add it to
save_local_enabled_features as features need to
be available before schema commitlog replay.
We skip the flush if save_local_enabled_features
is called from topology_state_load when the features
are migrated to system.topology and we don't need
strict durability.
We want to switch system.scylla_local table to the
schema commitlog, but load phases hamper here - schema
commitlog is initialized after phase1,
so a table which is using it should be moved to phase2,
but system.scylla_local contains features, and we need
them before schema commitlog initialization for
SCHEMA_COMMITLOG feature.
In this commit we are taking a different approach to
loading system tables. First, we load them all in
one pass in 'readonly' mode. In this mode, the table
cannot be written to and has not yet been assigned
a commit log. To achieve this we've added _readonly bool field
to the table class, it's initialized to true in table's
constructor. In addition, we changed the table constructor
to always assign nullptr to commitlog, and we trigger
an internal error if table.commitlog() property is accessed
while the table is in readonly mode. Then, after
triggering on_system_tables_loaded notifications on
feature_service and sstable_format_selector, we call
system_keyspace::mark_writable and eventually
table::mark_ready_for_writes which selects the
proper commitlog and marks the table as writable.
In sstable_compaction_test we drop several
mark_ready_for_writes calls since they are redundant,
the table has already been made writable in
env.make_table_for_tests call.
The table::commitlog function either returns the current
commitlog or causes an error if the table is readonly. This
didn't work for virtual tables, since they never called
mark_ready_for_writes. In this commit we add this
call to initialize_virtual_tables.
Our goal is to switch system.local table to schema
commitlog and stop doing flushes when we write to it.
This means it would be incorrect to read from this
table until schema commitlog is replayed.
On the other hand, we need truncation records
to be loaded before we start replaying schema
commitlog, since commitlog_replayer relies on them.
In this commit we inline the system_keyspace::setup
function and split its content into two parts. In
the first part, before schema commitlog replay,
we load truncation records. It's safe to load
them before schema commitlog replay since we intend
to let the flushes on writes to system.truncated
table. In the second part, after schema commitlog replay,
we do the rest of the job - build_bootstrap_info and
db::schema_tables::save_system_schema.
We decided to inline this function since there is
very low cohesion between the actions it's performing.
It's just simpler to reason about them individually.
This is a readability refactoring commit without observable changes
in behaviour.
initialize_virtual_tables logically belongs to virtual_tables module,
and it allows to make other functions in virtual_tables.cc
(register_virtual_tables, install_virtual_readers)
local to the module, which simplifies the matters a bit.
all_virtual_tables() is not needed anymore, all the references to
registered virtual tables are now local to virtual_tables module
and can just use virtual_tables variable directly.
On boot system keyspace is kicked to insert local info into system.local
table. Among other things there's dc:rack pair which sys.ks. gets from
its cache which, in turn, should have been previously initialized from
snitch on sys.ks. start. This patch makes the local info updating method
get the dc:rack from caller via argument. Callers, in turn, call snitch
directly, because these are main and cql_test_env startup routines.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
On boot several manipulations with system.local are performed.
1. The host_id value is selected from it with key = local
If not found, system_keyspace generates a new host_id, inserts the
new value into the table and returns back
2. The cluster_name is selected from it with key = local
Then it's system_keyspace that either checks that the name matches
the one from db::config, or inserts the db::config value into the
table
3. The row with key = local is updated with various info like versions,
listen, rpc and bcast addresses, dc, rack, etc. Unconditionally
All three steps are scattered over main, p.1 is called directly, p.2 and
p.3 are executed via system_keyspace::setup() that happens rather late.
Also there's some touch of this table from the cql_test_env startup code.
The proposal is to collect this setup into one place and execute it
early -- as soon as the system.local table is populated. This frees the
system_keyspace code from the logic of selecting host id and cluster
name leaving it to main and keeps it with only select/insert work.
refs: #2795
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closes#15082
Now, it is possible to load topology_features separately from the
topology struct. It will be used in the code that checks enabled
features on startup.
Those without `_as` suffix are just marked non-static
The `..._as` ones are made class methods (now they are local to system_keyspace.cc)
After that the `..._as` ones are patched to use `this->` instead of `qctx`
Closes#14890
* github.com:scylladb/scylladb:
system_keyspace: Stop using qctx in [gs]et_scylla_local_param_as()
system_keyspace: Reuse container() and _db member for flushing
system_keyspace: Make [gs]et_scylla_local_param_as() class methods
system_keyspace: De-static [gs]et_scylla_local_param()
These are now two .cc-local templatized helpers, but they are only
called by system_keyspace:: non-static methods, so can be such as well
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
All same-class callers are now non-static methods of system_keyspace,
all external callers do it via an object at hand.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
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 schema_tables() column-mapping code runs queries over system. table,
but it needs LOCAL_ONE CL and cherry-pick on caching, so regular
system_keyspace::execute_cql() won't work here.
However, since schema_tables is somewhat part of system_keyspace, it's
natural to let the former fetch private query_processor& from the latter
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The caller is raft_group0_client with sys.ks. dependency reference and
group0_state_machine with raft_group0_client exporing its sys.ks.
This makes it possible to instantly drop one more qctx reference
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The caller is raft_group0_client with sys.ks. dependency reference.
This allows to drop one qctx reference right at once
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Fortunately, this is pretty simple -- the only caller is storage_service
that has sharded<system_keysace> dependency reference
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closes#14824
This is to make m.s. initialization more solid and simplify sys.ks.::setup()
Closes#14832
* github.com:scylladb/scylladb:
system_keyspace: Remove unused snitch arg from setup()
messaging_service: Setup preferred IPs from config
Population of messageing service preferred IPs cache happens inside
system keyspace setup() call and it needs m.s. per ce and additionally
snitch. Moving preferred ip cache to initial configuration keeps m.s.
start more self-contained and keeps system_keyspace::setup() simpler.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
This template call is only used by system keyspace paxos methods. All
those methods are no longer static and can use system_keyspace::_qp
reference to real query processor instead of global qctx. The
execute_cql_with_timeout() wrapper is moved to system_keyspace to make
it work
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The service::paxos_state methods that call those already have system
keyspace reference at hand and can call method on an object
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Initialization of `system_keyspace` is now all done at once instead of
being spread out through the entire procedure. This is doable because
`query_processor` is now available early. A couple of FIXMEs have been
resolved.
Take references to services which are initialized earlier. The
references to `gossiper`, `storage_service` and `raft_group0_registry`
are no longer needed.
This will allow us to move the `make` step right after starting
`system_keyspace`.
