* indent the nested paragraphs of list items
* use table to format the time sequence for better
readability
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#14016
"Enable_repair_based_node_ops" is the name of an option, and the leading
character should be lowecase "e". so fix it.
Fixes#14017
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#14018
not all tables in system keyspace are volatile. among other things,
system.sstables and system.tablets are persisted using sstables like
regular user tables. so move them into the section where we have
other regular tables there.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
* Adds the new feature tutorial site to the docs
* fixes the unnecessary redirection (iot.scylladb.com)
Closes#13998
* github.com:scylladb/scylladb:
Skip unnecessary redirection
Add links to feature store tutorial
we changed the type of generation column in system.sstables
from bigint to timeuuid in 74e9e6dd1a
but that change failed to update the document accordingly. so let's
update the document to reflect the change.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13994
Fixes https://github.com/scylladb/scylladb/issues/13969
This commit enables publishing the docs for branch-5.3
The documentation for version 5.3 will be marked as
unstable until it is released, and an appropriate
warning is in place.
Closes#13977
`check_and_repair_cdc_streams` is an existing API which you can use when the
current CDC generation is suboptimal, e.g. after you decommissioned a node the
current generation has more stream IDs than you need. In that case you can do
`nodetool checkAndRepairCdcStreams` to create a new generation with fewer
streams.
It also works when you change number of shards on some node. We don't
automatically introduce a new generation in that case but you can use
`checkAndRepairCdcStreams` to create a new generation with restored
shard-colocation.
This PR implements the API on top of raft topology, it was originally
implemented using gossiper. It uses the `commit_cdc_generation` topology
transition state and a new `publish_cdc_generation` state to create new CDC
generations in a cluster without any nodes changing their `node_state`s in the
process.
Closes#13683
* github.com:scylladb/scylladb:
docs: update topology-over-raft.md
test: topology_experimental_raft: test `check_and_repair_cdc` API
raft topology: implement `check_and_repair_cdc_streams` API
raft topology: implement global request handling
raft topology: introduce `prepare_new_cdc_generation_data`
raft_topology: `get_node_to_work_on_opt`: return guard if no node found
raft topology: remove `node_to_work_on` from `commit_cdc_generation` transition
raft topology: separate `publish_cdc_generation` state
raft topology: non-node-specific `exec_global_command`
raft topology: introduce `start_operation()`
raft topology: non-node-specific `topology_mutation_builder`
topology_state_machine: introduce `global_topology_request`
topology_state_machine: use `uint16_t` for `enum_class`es
raft topology: make `new_cdc_generation_data_uuid` topology-global
Fixes https://github.com/scylladb/scylladb/issues/13808
This commit moves cloud instance recommendations from
the Requirements page to a new dedicated page.
The content of subsections is simply copy-pasted, but
I added the introduction and metadata for better
searchability.
Fixes https://github.com/scylladb/scylladb/issues/13915
This commit fixes broken links to the Enterprise docs.
They are links to the enterprise branch, which is not
published. The links to the Enterprise docs should include
"stable" instead of the branch name.
This commit must be backported to branch-5.2, because
the broken links are present in the published 5.2 docs.
Closes#13917
Fixes https://github.com/scylladb/scylladb/issues/13857
This commit adds the OS support for ScyllaDB Enterprise 2023.1.
The support is the same as for ScyllaDB Open Source 5.2, on which
2023.1 is based.
After this commit is merged, it must be backported to branch-5.2.
In this way, it will be merged to branch-2023.1 and available in
the docs for Enterprise 2023.1
Closes: #13858
Fixes https://github.com/scylladb/scylladb/issues/13805
This commit fixes the redirection required by moving the Glossary
page from the top of the page tree to the Reference section.
As the change was only merged to master (not to branch-5.2),
it is not working for version 5.2, which is now the latest stable
version.
For this reason, "stable" in the path must be replaced with "master".
Closes#13847
It was already outdated before this PR.
Describe the version of topology state machine implemented in this PR.
Fix some typos and make it proper markdown so it renders nicely on
GitHub etc.
This commit changes the configuration in the conf.py
file to make branch-5.2 the latest version and
remove it from the list of unstable versions.
As a result, the docs for version 5.2 will become
the default for users accessing the ScyllaDB Open Source
documentation.
This commit should be merged as soon as version 5.2
is released.
Closes#13681
@annastuchlik please review
Closes#13691
* github.com:scylladb/scylladb:
adding documentation for integration with MindsDB
adding documentation for integration with MindsDB
This PR introduces an experimental feature called "tablets". Tablets are
a way to distribute data in the cluster, which is an alternative to the
current vnode-based replication. Vnode-based replication strategy tries
to evenly distribute the global token space shared by all tables among
nodes and shards. With tablets, the aim is to start from a different
side. Divide resources of replica-shard into tablets, with a goal of
having a fixed target tablet size, and then assign those tablets to
serve fragments of tables (also called tablets). This will allow us to
balance the load in a more flexible manner, by moving individual tablets
around. Also, unlike with vnode ranges, tablet replicas live on a
particular shard on a given node, which will allow us to bind raft
groups to tablets. Those goals are not yet achieved with this PR, but it
lays the ground for this.
Things achieved in this PR:
- You can start a cluster and create a keyspace whose tables will use
tablet-based replication. This is done by setting `initial_tablets`
option:
```
CREATE KEYSPACE test WITH replication = {'class': 'NetworkTopologyStrategy',
'replication_factor': 3,
'initial_tablets': 8};
```
All tables created in such a keyspace will be tablet-based.
Tablet-based replication is a trait, not a separate replication
strategy. Tablets don't change the spirit of replication strategy, it
just alters the way in which data ownership is managed. In theory, we
could use it for other strategies as well like
EverywhereReplicationStrategy. Currently, only NetworkTopologyStrategy
is augmented to support tablets.
- You can create and drop tablet-based tables (no DDL language changes)
- DML / DQL work with tablet-based tables
Replicas for tablet-based tables are chosen from tablet metadata
instead of token metadata
Things which are not yet implemented:
- handling of views, indexes, CDC created on tablet-based tables
- sharding is done using the old method, it ignores the shard allocated in tablet metadata
- node operations (topology changes, repair, rebuild) are not handling tablet-based tables
- not integrated with compaction groups
- tablet allocator piggy-backs on tokens to choose replicas.
Eventually we want to allocate based on current load, not statically
Closes#13387
* github.com:scylladb/scylladb:
test: topology: Introduce test_tablets.py
raft: Introduce 'raft_server_force_snapshot' error injection
locator: network_topology_strategy: Support tablet replication
service: Introduce tablet_allocator
locator: Introduce tablet_aware_replication_strategy
locator: Extract maybe_remove_node_being_replaced()
dht: token_metadata: Introduce get_my_id()
migration_manager: Send tablet metadata as part of schema pull
storage_service: Load tablet metadata when reloading topology state
storage_service: Load tablet metadata on boot and from group0 changes
db, migration_manager: Notify about tablet metadata changes via migration_listener::on_update_tablet_metadata()
migration_notifier: Introduce before_drop_keyspace()
migration_manager: Make prepare_keyspace_drop_announcement() return a future<>
test: perf: Introduce perf-tablets
test: Introduce tablets_test
test: lib: Do not override table id in create_table()
utils, tablets: Introduce external_memory_usage()
db: tablets: Add printers
db: tablets: Add persistence layer
dht: Use last_token_of_compaction_group() in split_token_range_msb()
locator: Introduce tablet_metadata
dht: Introduce first_token()
dht: Introduce next_token()
storage_proxy: Improve trace-level logging
locator: token_metadata: Fix confusing comment on ring_range()
dht, storage_proxy: Abstract token space splitting
Revert "query_ranges_to_vnodes_generator: fix for exclusive boundaries"
db: Exclude keyspace with per-table replication in get_non_local_strategy_keyspaces_erms()
db: Introduce get_non_local_vnode_based_strategy_keyspaces()
service: storage_proxy: Avoid copying keyspace name in write handler
locator: Introduce per-table replication strategy
treewide: Use replication_strategy_ptr as a shorter name for abstract_replication_strategy::ptr_type
locator: Introduce effective_replication_map
locator: Rename effective_replication_map to vnode_effective_replication_map
locator: effective_replication_map: Abstract get_pending_endpoints()
db: Propagate feature_service to abstract_replication_strategy::validate_options()
db: config: Introduce experimental "TABLETS" feature
db: Log replication strategy for debugging purposes
db: Log full exception on error in do_parse_schema_tables()
db: keyspace: Remove non-const replication strategy getter
config: Reformat
This commit moves the Glossary page to the Reference
section. In addition, it adds the redirection so that
there are no broken links because of this change
and fixes a link to a subsection of Glossary.
Closes#13664
Fixes https://github.com/scylladb/scylladb/issues/13578
Now that the documentation is versioned, we can remove
the .. versionadded:: and .. versionchanged:: information
(especially that the latter is hard to maintain and now
outdated), as well as the outdated information about
experimental features in very old releases.
This commit removes that information and nothing else.
Closes#13680
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
Update the `Generation switching` section: most of the existing
description landed in `Gossiper-based topology changes` subsection, and
a new subsection was added to describe Raft group 0 based topology
changes. Marked as WIP - we expect further development in this area
soon.
The existing gossiper-based description was also updated a bit.
