Along the way, our flat structure for docs was changed
to categorize the documents, but service_levels.md was forward-ported
later and missed the created directory structure, so it was created
as a sole document in the top directory. Move it to where the other
similar docs live.
Message-Id: <68079d9dd511574ee32fce15fec541ca75fca1e2.1640248754.git.sarna@scylladb.com>
The description in protocols.md of the Redis protocol server in Scylla
explains how its port can be configured, but not how the listening IP
address can be configured. It turns out that the same "rpc_address" that
controls CQL's and Thrift's IP address also applies to Redis. So let's
document that.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20211208160206.1290916-1-nyh@scylladb.com>
Other than looking sane, this change continues the founded by the
--workdir option tradition of freeing the developer form annoying
necessity to type too many options when scylla is started by hand
for devel purposes.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20211116104815.31822-1-xemul@scylladb.com>
Add "rows" field to system.large_partitions. Add partitions to the
table when they are too large or have too many rows.
Fixes#9506
Signed-off-by: Michael Livshin <michael.livshin@scylladb.com>
Closes#9577
A config option value is reported as 'text' type and contains
a string as it would looks like in json config.
The table is UPDATE-able. Only the 'value' columnt can be set
and the value accepted must be string. It will be converted into
the option type automatically, however in current implementation
is't not 100% precise -- conversion is lexicographical cast which
only works for simple types. However, liveupdate-able values are
only of those types, so it works in supported cases.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Contains all version related information (`nodetool version` and more).
Example printout:
(cqlsh) select * from system.versions;
key | build_id | build_mode | version
-------+------------------------------------------+------------+-------------------------------
local | aaecce2f5068b0160efd04a09b0e28e100b9cd9e | dev | 4.6.dev-0.20211021.0d744fd3fa
Loosly contains the equivalent of the `nodetool info` command, with some
notable differences:
* Protocol server related information is in `system.protocol_servers`;
* Information about memory, memtable and cache is reformatted to be
tailored to scylla: C* specific terminology and metrics are dropped;
* Information that doesn't change and is already in `system.local` is
not contained;
* Added trace-probability too (`nodetool gettraceprobability`);
TODO(follow-up): exceptions.
Lists all the client protocol server and their status. Example output:
(cqlsh) select * from system.protocol_servers;
name | is_running | listen_addresses | protocol | protocol_version
------------------+------------+---------------------------------------+----------+------------------
native transport | True | ['127.0.0.1:9042', '127.0.0.1:19042'] | cql | 3.3.1
alternator | False | [] | dynamodb |
rpc | False | [] | thrift | 20.1.0
redis | False | [] | redis |
This prints the equivalent of `nodetool statusbinary` and the "Thrift
active" and "Native Transport active" fields from the `nodetool info`
output with some additional information:
* It contains alternator and redis status;
* It contains the protocol version;
* It contains the listen addresses (if respective server is running);
Introduce new syntax in IDL compiler to allow generating
registration/sending code for RPC verbs:
```
verb [[attr1, attr2...] my_verb (args...) -> return_type;
```
`my_verb` RPC verb declaration corresponds to the
`netw::messaging_verb::MY_VERB` enumeration value to identify the
new RPC verb.
For a given `idl_module.idl.hh` file, a registrator class named
`idl_module_rpc_verbs` will be created if there are any RPC verbs
registered within the IDL module file.
These are the methods being created for each RPC verb:
```
static void register_my_verb(netw::messaging_service* ms, std::function<return_type(args...)>&&);
static future<> unregister_my_verb(netw::messaging_service* ms);
static future<> send_my_verb(netw::messaging_service* ms, netw::msg_addr id, args...);
```
Each method accepts a pointer to an instance of `messaging_service`
object, which contains the underlying seastar RPC protocol
implementation, that is used to register verbs and pass messages.
There is also a method to unregister all verbs at once:
```
static future<> unregister(netw::messaging_service* ms);
```
The following attributes are supported when declaring an RPC verb
in the IDL:
* `[[with_client_info]]` - the handler will contain a const reference to
an `rpc::client_info` as the first argument.
* `[[with_timeout]]` - an additional `time_point` parameter is supplied
to the handler function and `send*` method uses `send_message_*_timeout`
variant of internal function to actually send the message.
* `[[one_way]]` - the handler function is annotated by
`future<rpc::no_wait_type>` return type to designate that a client
doesn't need to wait for an answer.
The `-> return_type` clause is optional for two-way messages. If omitted,
the return type is set to be `future<>`.
For one-way verbs, the use of return clause is prohibited and the
signature of `send*` function always returns `future<>`.
No existing code is affected.
Ref: #1456Closes#9359
* github.com:scylladb/scylla:
idl: support generating boilerplate code for RPC verbs
idl: allow specifying multiple attributes in the grammar
message: messaging_service: extract RPC protocol details and helpers into a separate header
The pull_github_pr.sh script is preferred over colorful github
buttons, because it's designed to always assign proper authors.
It also works for both single- and multi-patch series, which
makes the merging process more universal.
Message-Id: <b982b650442456b988e1cea59aa5ad221207b825.1633101849.git.sarna@scylladb.com>
Introduce new syntax in IDL compiler to allow generating
registration/sending code for RPC verbs:
verb [[attr1, attr2...] my_verb (args...) -> return_type;
`my_verb` RPC verb declaration corresponds to the
`netw::messaging_verb::MY_VERB` enumeration value to identify the
new RPC verb.
For a given `idl_module.idl.hh` file, a registrator class named
`idl_module_rpc_verbs` will be created if there are any RPC verbs
registered within the IDL module file.
These are the methods being created for each RPC verb:
static void register_my_verb(netw::messaging_service* ms, std::function<return_type(args...)>&&);
static future<> unregister_my_verb(netw::messaging_service* ms);
static future<> send_my_verb(netw::messaging_service* ms, netw::msg_addr id, args...);
Each method accepts a pointer to an instance of `messaging_service`
object, which contains the underlying seastar RPC protocol
implementation, that is used to register verbs and pass messages.
There is also a method to unregister all verbs at once:
static future<> unregister(netw::messaging_service* ms);
The following attributes are supported when declaring an RPC verb
in the IDL:
* [[with_client_info]] - the handler will contain a const reference to
an `rpc::client_info` as the first argument.
* [[with_timeout]] - an additional `time_point` parameter is supplied
to the handler function and `send*` method uses `send_message_*_timeout`
variant of internal function to actually send the message.
* [[one_way]] - the handler function is annotated by
`future<rpc::no_wait_type>` return type to designate that a client
doesn't need to wait for an answer.
The `-> return_type` clause is optional for two-way messages. If omitted,
the return type is set to be `future<>`.
For one-way verbs, the use of return clause is prohibited and the
signature of `send*` function always returns `future<>`.
No existing code is affected.
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Related issues: scylladb/sphinx-scylladb-theme#87
All the variables related to the multiversion extension are now defined in conf.py instead of using the GitHub Actions file.
How to test this PR
Run make multiversionpreview on docs folder. When you open https://0.0.0.0:5500, the browser should render the documentation site.
Closes#7957
We never want to listen on port 0, even if configured so.
When the listen port is set to 0, the OS will choose the
port randomly, which makes it useless for communicating
with other nodes in the cluster, since we don't support that.
Also, it causes the listen_ports_conf_test internode_ssl_test
to fail since it expects to disable listening on storage_port
or ssl_storage_port when set to 0, as seen in
https://github.com/scylladb/scylla-dtest/issues/2174.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
A user complained that the "Running Alternator" section was confusing.
It didn't say outright which two configurations are necessary and you
had to read a few paragraph to reach it, and it mixed the YAML names
of options and the command-line names, which are subtly different.
This patch tries to improve this.
Unfortunately the scylla.docs.scylladb.com formatter which generates
https://scylla.docs.scylladb.com/master/alternator/alternator.html
doesn't know how to recognize HTTP URLs and convert them into proper
HTML links (something which github's formatter does).
So convert the two URLs we had in alternator.md into markdown links
which both github and our formatter recognize.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
In the last year, four new features were added to DynamoDB which we
don't yet support - Kinesis Streams, PartiQL, Contributor Insights and
Export to S3. Let's document them as missing Alternator features, and
point to the four newly-created issues about these features.
Refs #8786
Refs #8787
Refs #8788
Refs #8789
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210603125825.1179171-1-nyh@scylladb.com>
Reopening #8286 since the token metadata fix that allows `Everywhere` strategy tables to work with RBO (#8536) has been merged.
---
Currently when a node wants to create and broadcast a new CDC generation
it performs the following steps:
1. choose the generation's stream IDs and mapping (how this is done is
irrelevant for the current discussion)
2. choose the generation's timestamp by taking the current time
(according to its local clock) and adding 2 * ring_delay
3. insert the generation's data (mapping and stream IDs) into
system_distributed.cdc_generation_descriptions, using the
generation's timestamp as the partition key (we call this table
the "old internal table" below)
4. insert the generation's timestamp into the "CDC_STREAMS_TIMESTAMP"
application state.
The timestamp spreads epidemically through the gossip protocol. When
nodes see the timestamp, they retrieve the generation data from the
old internal table.
Unfortunately, due to the schema of the old internal table, where
the entire generation data is stored in a single cell, step 3 may fail for
sufficiently large generations (there is a size threshold for which step
3 will always fail - retrying the operation won't help). Also the old
internal table lies in the system_distributed keyspace that uses
SimpleStrategy with replication factor 3, which is also problematic; for
example, when nodes restart, they must reach at least 2 out of these 3
specific replicas in order to retrieve the current generation (we write
and read the generation data with QUORUM, unless we're a single-node
cluster, where we use ONE). Until this happens, a restarting
node can't coordinate writes to CDC-enabled tables. It would be better
if the node could access the last known generation locally.
The commit introduces a new table for broadcasting generation data with
the following properties:
- it uses a better schema that stores the data in multiple rows, each
of manageable size
- it resides in a new keyspace that uses EverywhereStrategy so the
data will be written to every node in the cluster that has a token in
the token ring
- the data will be written using CL=ALL and read using CL=ONE; thanks
to this, restarting node won't have to communicate with other nodes
to retrieve the data of the last known generation. Note that writing
with CL=ALL does not reduce availability: creating a new generation
*requires* all nodes to be available anyway, because they must learn
about the generation before their clocks go past the generation's
timestamp; if they don't, partitions won't be mapped to stream IDs
consistently across the cluster
- the partition key is no longer the generation's timestamp. Because it
was that way in the old internal table, it forced the algorithm to
choose the timestamp *before* the generation data was inserted into
the table. What if the inserting took a long time? It increased the
chance that nodes would learn about the generation too late (after
their clocks moved past its timestamp). With the new schema we will
first insert the generation data using a randomly generated UUID as
the partition key, *then* choose the timestamp, then gossip both the
timestamp and the UUID.
Observe that after a node learns about a generation broadcasted using
this new method through gossip it will retrieve its data very quickly
since it's one of the replicas and it can use CL=ONE as it was
written using CL=ALL.
The generation's timestamp and the UUID mentioned in the last point form
a "generation identifier" for this new generation. For passing these new
identifiers around, we introduce the cdc::generation_id_v2 type.
Fixes#7961.
---
For optimal review experience it is best to first read the updated design notes (you can read them rendered here: https://github.com/kbr-/scylla/blob/cdc-gen-table/docs/design-notes/cdc.md), specifically the ["Generation switching"](https://github.com/kbr-/scylla/blob/cdc-gen-table/docs/design-notes/cdc.md#generation-switching) section followed by the ["Internal generation descriptions table V1 and upgrade procedure"](https://github.com/kbr-/scylla/blob/cdc-gen-table/docs/design-notes/cdc.md#internal-generation-descriptions-table-v1-and-upgrade-procedure) section, then read the commits in topological order.
dtest gating run (dev): https://jenkins.scylladb.com/job/scylla-master/job/byo/job/byo_build_tests_dtest/1160/
unit tests (dev) passed locally
Closes#8643
* github.com:scylladb/scylla:
docs: update cdc.md with info about the new internal table
sys_dist_ks: don't create old CDC generations table on service initialization
sys_dist_ks: rename all_tables() to ensured_tables()
cdc: when creating new generations, use format v2 if possible
main: pass feature_service to cdc::generation_service
gms: introduce CDC_GENERATIONS_V2 feature
cdc: introduce retrieve_generation_data
test: cdc: include new generations table in permissions test
sys_dist_ks: increase timeout for create_cdc_desc
sys_dist_ks: new table for exchanging CDC generations
tree-wide: introduce cdc::generation_id_v2
This series introduces service level syntax borrowed from https://docs.scylladb.com/using-scylla/workload-prioritization/ , but without workload prioritization itself - just for the sake of using identical syntax to provide different parameters later. The new parameters may include:
* per-service-level timeouts
* oltp/olap declaration, which may change the way Scylla treats long requests - e.g. time them out (the oltp way) or keep them sustained with empty pages (the olap way)
Refs #7617Closes#7867
* github.com:scylladb/scylla:
transport: initialize query state with service level controller
main: add initializing service level data accessor
service: make enable_shared_from_this inheritance public
cql3: add SERVICE LEVEL syntax (without an underscore)
unit test: Add unit test for per user sla syntax
cql: Add support for service level cql queries
auth: Add service_level resource for supporting in authorization of cql service_level
cql: Support accessing service_level_controller from query state
instantiate and initialize the service_level_controller
qos: Add a standard implementation for service level data accessor
qos: add waiting for the updater future
service/qos: adding service level controller
service_levels: Add documentation for distributed tables
service/qos: adding service level table to the distributed keyspace
service/qos: add common definitions
auth: add support for role attributes
