It is already set by schema_maker. In tablets_test we will depend on
the id being the same as that set in the schema_builder, so don't
change it to something else.
Currently, scans are splitting partition ranges around tokens. This
will have to change with tablets, where we should split at tablet
boundaries.
This patch introduces token_range_splitter which abstracts this
task. It is provided by effective_replication_map implementation.
This reverts commit 95bf8eebe0.
Later patches will adapt this code to work with token_range_splitter,
and the unit test added by the reverted commit will start to fail.
The unit test asks the query_ranges_to_vnodes_generator to split the range:
[t:end, t+1:start)
around token t, and expects the generator to produce an empty range
[t:end, t:end]
After adapting this code to token_range_splitter, the input range will
not be split because it is recognized as adjacent to t:end, and the
optimization logic will not kick in. Rather than adding more logic to
handle this case, I think it's better to drop the optimization, as it
is not very useful (rarely happens) and not required for correctness.
This allows update_pending_ranges(), invoked on keyspace creation, to
succeed in the presence of keyspaces with per-table replication
strategy. It will update only vnode-based erms, which is intended
behavior, since only those need pending ranges updated.
This change will also make node operations like bootstrap, repair,
etc. to work (not fail) in the presence of keyspaces with per-table
erms, they will just not be replicated using those algorithms.
Before, these would fail inside get_effective_replication_map(), which
is forbidden for keyspaces with per-table replication.
It's meant to be used in places where currently
get_non_local_strategy_keyspaces() is used, but work only with
keyspaces which use vnode-based replication strategy.
Will be used by tablet-based replication strategies, for which
effective replication map is different per table.
Also, this patch adapts existing users of effective replication map to
use the per-table effective replication map.
For simplicity, every table has an effective replication map, even if
the erm is per keyspace. This way the client code can be uniform and
doesn't have to check whether replication strategy is per table.
Not all users of per-keyspace get_effective_replication_map() are
adapted yet to work per-table. Those algorithms will throw an
exception when invoked on a keyspace which uses per-table replication
strategy.
With tablet-based replication strategies it will represent replication
of a single table.
Current vnode_effective_replication_map can be adapted to this interface.
This will allow algorithms like those in storage_proxy to work with
both kinds of replication strategies over a single abstraction.
The only reason why it's there (right next to compaction_fwd.hh) is
because the database::table_truncate_state subclass needs the definition
of compaction_manager::compaction_reenabler subclass.
However, the former sub is not used outside of database.cc and can be
defined in .cc. Keeping it outside of the header allows dropping the
compaction_manager.hh from database.hh thus greatly reducing its fanout
over the code (from ~180 indirect inclusions down to ~20).
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closes#13622
Introduce a new table `CDC_GENERATIONS_V3` (`system.cdc_generations_v3`).
The table schema is a copy-paste of the `CDC_GENERATIONS_V2` schema. The
difference is that V2 lives in `system_distributed_keyspace` and writes to it
are distributed using regular `storage_proxy` replication mechanisms based on
the token ring. The V3 table lives in `system_keyspace` and any mutations
written to it will go through group 0.
Extend the `TOPOLOGY` schema with new columns:
- `new_cdc_generation_data_uuid` will be stored as part of a bootstrapping
node's `ring_slice`, it stores UUID of a newly introduced CDC
generation which is used as partition key for the `CDC_GENERATIONS_V3`
table to access this new generation's data. It's a regular column,
meaning that every row (corresponding to a node) will have its own.
- `current_cdc_generation_uuid` and `current_cdc_generation_timestamp`
together form the ID of the newest CDC generation in the cluster.
(the uuid is the data key for `CDC_GENERATIONS_V3`, the timestamp is
when the CDC generation starts operating). Those are static columns
since there's a single newest CDC generation.
When topology coordinator handles a request for node to join, calculate a new
CDC generation using the bootstrapping node's tokens, translate it to mutation
format, and insert this mutation to the CDC_GENERATIONS_V3 table through group 0
at the same time we assign tokens to the node in Raft topology. The partition
key for this data is stored in the bootstrapping node's `ring_slice`.
After inserting new CDC generation data , we need to pick a timestamp for this
generation and commit it, telling all nodes in the cluster to start using the
generation for CDC log writes once their clocks cross that timestamp.
We introduce a separate step to the bootstrap saga, before
`write_both_read_old`, called `commit_cdc_generation`. In this step, the
coordinator takes the `new_cdc_generation_data_uuid` stored in a bootstrapping
node's `ring_slice` - which serves as the key to the table where the CDC
generation data is stored - and combines it with a timestamp which it generates
a bit into the future (as in old gossiper-based code, we use 2 * ring_delay, by
default 1 minute). This gives us a CDC generation ID which we commit into the
topology state as the `current_cdc_generation_id` while switching the saga to
the next step, `write_both_read_old`.
Once a new CDC generation is committed to the cluster by the topology
coordinator, we also need to publish it to the user-facing description tables so
CDC applications know which streams to read from.
This uses regular distributed table writes underneath (tables living in the
`system_distributed` keyspace) so it requires `token_metadata` to be nonempty.
We need a hack for the case of bootstrapping the first node in the cluster -
turning the tokens into normal tokens earlier in the procedure in
`token_metadata`, but this is fine for the single-node case since no streaming
is happening.
When a node notices that a new CDC generation was introduced in
`storage_service::topology_state_load`, it updates its internal data structures
that are used when coordinating writes to CDC log tables.
We include the current CDC generation data in topology snapshot transfers.
Some fixes and refactors included.
Closes#13385
* github.com:scylladb/scylladb:
docs: cdc: describe generation changes using group 0 topology coordinator
cdc: generation_service: add a FIXME
cdc: generation_service: add legacy_ prefix for gossiper-based functions
storage_service: include current CDC generation data in topology snapshots
db: system_keyspace: introduce `query_mutations` with range/slice
storage_service: hold group 0 apply mutex when reading topology snapshot
service: raft_group0_client: introduce `hold_read_apply_mutex`
storage_service: use CDC generations introduced by Raft topology
raft topology: publish new CDC generation to the user description tables
raft topology: commit a new CDC generation on node bootstrap
raft topology: create new CDC generation data during node bootstrap
service: topology_state_machine: make topology::find const
db: system_keyspace: small refactor of `load_topology_state`
cdc: generation: extract pure parts of `make_new_generation` outside
db: system_keyspace: add storage for CDC generations managed by group 0
service: topology_state_machine: better error checking for state name (de)serialization
service: raft: plumbing `cdc::generation_service&`
cdc: generation: `get_cdc_generation_mutations`: take timestamp as parameter
cdc: generation: make `topology_description_generator::get_sharding_info` a parameter
sys_dist_ks: make `get_cdc_generation_mutations` public
sys_dist_ks: move find_schema outside `get_cdc_generation_mutations`
sys_dist_ks: move mutation size threshold calculation outside `get_cdc_generation_mutations`
service/raft: group0_state_machine: signal topology state machine in `load_snapshot`
The tombstone_gc was documented as experimental in version 5.0.
It is no longer experimental in version 5.2.
This commit updates the information about the option.
Closes#13469
this the standard library offers
`std::lexicographical_compare_threeway()`, and we never uses the
last two addition parameters which are not provided by
`std::lexicographical_compare_threeway()`. there is no need to have
the homebrew version of trichotomic compare function.
in this change,
* all occurrences of `lexicographical_tri_compare()` are replaced
with `std::lexicographical_compare_threeway()`.
* ``lexicographical_tri_compare()` is dropped.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13615
C++20 compiler is able to generate defaulted operator== and
operator!=. and the default generated operators behaves exactly
the same as the ones crafted by us. so let's it do its job.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13614
in `make_group0_history_state_id_mutation`, when adding a new entry to
the group 0 history table, if the parameter `gc_older_than` is engaged,
we create a range tombstone in the mutation which deletes entries older
than the new one by `gc_older_than`. In particular if
`gc_older_than = 0`, we want to delete all older entries.
There was a subtle bug there: we were using millisecond resolution when
generating the tombstone, while the provided state IDs used microsecond
resolution. On a super fast machine it could happen that we managed to
perform two schema changes in a single millisecond; this happened
sometimes in `group0_test.test_group0_history_clearing_old_entries`
on our new CI/promotion machines, causing the test to fail because the
tombstone didn't clear the entry correspodning to the previous schema
change when performing the next schema change (since they happened in
the same millisecond).
Use microsecond resolution to fix that. The consecutive state IDs used
in group 0 mutations are guaranteed to be strictly monotonic at
microsecond resolution (see `generate_group0_state_id` in
service/raft/raft_group0_client.cc).
Fixes#13594Closes#13604
* github.com:scylladb/scylladb:
db: system_keyspace: use microsecond resolution for group0_history range tombstone
utils: UUID_gen: accept decimicroseconds in min_time_UUID
Move gms::arrival_window to api/failure_detector which is its only user.
and get rid of the rest, which is not used, now that we use direct_failure_detector instead.
TODO: integare direct_failure_detector with failure_detector api.
Closes#13576
* github.com:scylladb/scylladb:
gms: get rid of unused failure_detector
api: failure_detector: remove false dependency on failure_detector::arrival_window
test: rest_api: add test_failure_detector
Fixes a problem when raft-based topology is enabled, which loads
topology from storage. It starts by clearing topology and then adding
nodes one by one. Before this patch, this violates internal invariant
of topology object which puts the local node as the first node. This
would manifest by triggering an assert in topology::pop_node() which
throws if popping the node at index 0 in order to keep the information
about local node around. This is normally prevented by a check in
topology::remove_node() which avoid calling pop_node() if removing the
local node. But since there is no node which is marked as local, this
check allows the first node to be popped.
To fix the problem I lift the invariant that local node is always in
_nodes. We still have information about local node in config. Instead
of keeping it in _nodes, we recognize it as part of indexing. We also
allow removing the local node like a regular node.
The path which reloads topology works correctly after this, the local
node will be recognized when (if) it is added to the topology.
Fixes#13495Closes#13498
* github.com:scylladb/scylladb:
locator: topology: Fix move assignment
locator: topology: Add printer
tests: topology: Test that topology clearing preserves information about local node
locator: topology: Recognize local node as part of indexing it
locator: topology: Fix get_location(ep) for local node
locator: topology: Fix typo
locator: topology: Preserve config when cloning
in `make_group0_history_state_id_mutation`, when adding a new entry to
the group 0 history table, if the parameter `gc_older_than` is engaged,
we create a range tombstone in the mutation which deletes entries older
than the new one by `gc_older_than`. In particular if
`gc_older_than = 0`, we want to delete all older entries.
There was a subtle bug there: we were using millisecond resolution when
generating the tombstone, while the provided state IDs used microsecond
resolution. On a super fast machine it could happen that we managed to
perform two schema changes in a single millisecond; this happened
sometimes in `group0_test.test_group0_history_clearing_old_entries`
on our new CI/promotion machines, causing the test to fail because the
tombstone didn't clear the entry correspodning to the previous schema
change when performing the next schema change (since they happened in
the same millisecond).
Use microsecond resolution to fix that. The consecutive state IDs used
in group 0 mutations are guaranteed to be strictly monotonic at
microsecond resolution (see `generate_group0_state_id` in
service/raft/raft_group0_client.cc).
Fixes#13594
this is a part of a series to migrating from `operator<<(ostream&, ..)`
based formatting to fmtlib based formatting. the goal here is to enable
fmtlib to print `function_name` without the help of `operator<<`.
the corresponding `operator<<()` are dropped dropped in this change,
as all its callers are now using fmtlib for formatting now.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13608
this is a part of a series to migrating from `operator<<(ostream&, ..)` based formatting to fmtlib based formatting. the goal here is to enable fmtlib to print `dht::token` without the help of `operator<<`.
the corresponding `operator<<()` is preserved in this change, as it has lots of users in this project, we will tackle them case-by-case in follow-up changes.
also, the forward declaration of `operator<<(ostream&, constdht::token&)` in `dht/i_partitioner.hh` is removed. ias it not necessary.
Refs https://github.com/scylladb/scylladb/issues/13245Closes#13610
* github.com:scylladb/scylladb:
dht: remove unnecessarily forward declaration
dht: specialize fmt::formatter<dht::token>
this is a part of a series to migrating from `operator<<(ostream&, ..)`
based formatting to fmtlib based formatting. the goal here is to enable
fmtlib to print `component_type` without the help of `operator<<`.
the corresponding `operator<<()` are dropped dropped in this change,
as all its callers are now using fmtlib for formatting now.
also, please note, to enable fmtlib to format `std::set<component_type>`
in `test/boost/sstable_3_x_test.cc` , we need to include
`<fmt/ranges.h>` in that source file.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13598
this is a part of a series to migrating from `operator<<(ostream&, ..)`
based formatting to fmtlib based formatting. the goal here is to enable
fmtlib to print `stream_reason` without the help of `operator<<`.
please note, because we still cannot use the generic formatter for
std::unordered_map provided by fmtlib, so in order to drop `operator<<`
for `stream_reason`, and to print `unordered_map<stream_reason>`,
`fmt::join()` is used as a temporary solution. we will audit all
`fmt::join()` calls, after removing the homebrew formatter of
`std::unordered_map`.
the corresponding `operator<<()` are dropped dropped in this change,
as all its callers are now using fmtlib for formatting now.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13609
this change replaces all occurrences of `boost::lexical_cast<std::string>`
in the source tree with `fmt::to_string()`. for couple reasons:
* `boost::lexical_cast<std::string>` is longer than `fmt::to_string()`,
so the latter is easier to parse and read.
* `boost::lexical_cast<std::string>` creates a stringstream under the
hood, so it can use the `operator<<` to stringify the given object.
but stringstream is known to be less performant than fmtlib.
* we are migrating to fmtlib based formatting, see #13245. so
using `fmt::to_string()` helps us to remove yet another dependency
on `operator<<`.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13611
The legacy failure_detector is now unused and can be removed.
TODO: integare direct_failure_detector with failure_detector api.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
