Recently, coordinator_result was introduced as an alternative for
exceptions. It was placed in the main "exceptions/exceptions.hh" header,
which virtually every single source file in Scylla includes.
But unfortunately, it brings in some heavy header files and templates,
leading to a lot of wasted build time - ClangBuildAnalyzer measured that
we include exceptions.hh in 323 source files, taking almost two seconds
each on average.
In this patch, we split the coordinator_result feature into a separate
header file, "exceptions/coordinator_result", and only the few places
which need it include the header file. Unfortunately, some of these
few places are themselves header, so the new header file ends up being
included in 100 source files - but 100 is still much less than 323 and
perhaps we can reduce this number 100 later.
After this patch, the total Scylla object-file size is reduced by 6.5%
(the object size is a proxy for build time, which I didn't directly
measure). ClangBuildAnalyzer reports that now each of the 323 includes
of exceptions.hh only takes 80ms, coordinator_result.hh is only included
100 times, and virtually all the cost to include it comes from Boost's
result.hh (400ms per inclusion).
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20220228204323.1427012-1-nyh@scylladb.com>
The call returns a chunked_vector with client_data's. For now
only the native transport implements it, others return empty
vector.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Right now when the client state changes the respective update is
performed on the system.clients table. While doing it some bits
from this state are lost from the in-memory structures. For the
sake of exporting this information we need to track whether the
connected client goes authenticating or is already ready.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
The event_notifier is private server subclass that's created once
per server to handle events from storage_service. The notifier needs
gossiper that already sits on the server, and to get it the simplest
way is to equip notifier with the server backreference. Since these
two objects are in strict 1:1 relation this reference is safe.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The gossiper is needed by the transport::event_notifier. There's
already gossiper reference on the transport controller, but it's
a local reference, because controller doesn't need more. This
patch upgrages controller reference to sharded<> and propagates
it further up to the server.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
This warning can catch a virtual function that thinks it
overrides another, but doesn't, because the two functions
have different signatures. This isn't very likely since most
of our virtual functions override pure virtuals, but it's
still worth having.
Enable the warning and fix numerous violations.
Closes#9347
"
`function_call` AST nodes are created for each function
with side effects in a CQL query, i.e. non-deterministic
functions (`uuid()`, `now()` and some others timeuuid-related).
These nodes are evaluated either when a query itself is executed
or query restrictions are computed (e.g. partition/clustering
key ranges for LWT requests).
We need to cache the calls since otherwise when handling a
`bounce_to_shard` request for an LWT query, we can possibly
enter an infinite bouncing loop (in case a function is used
to calculate partition key ranges for a query), since the
results can be different each time.
Furthermore, we don't support bouncing more than one time.
Returning `bounce_to_shard` message more than one time
will result in a crash.
Caching works only for LWT statements and only for the function
calls that affect partition key range computation for the query.
`variable_specifications` class is renamed to `prepare_context`
and generalized to record information about each `function_call`
AST node and modify them, as needed:
* Check whether a given function call is a part of partition key
statement restriction.
* Assign ids for caching if above is true and the call is a part
of an LWT statement.
There is no need to include any kind of statement identifier
in the cache key since `query_options` (which holds the cache)
is limited to a single statement, anyway.
Function calls are indexed by the order in which they appear
within a statement while parsing. There is no need to
include any kind of statement identifier to the cache key
since `query_options` (which holds the cache) is limited
to a single statement, anyway.
Note that `function_call::raw` AST nodes are not created
for selection clauses of a SELECT statement hence they
can only accept only one of the following things as parameters:
* Other function calls.
* Literal values.
* Parameter markers.
In other words, only parameters that can be immediately reduced
to a byte buffer are allowed and we don't need to handle
database inputs to non-pure functions separately since they
are not possible in this context. Anyhow, we don't even have
a single non-pure function that accepts arguments, so precautions
are not needed at the moment.
Add a test written in `cql-pytest` framework to verify
that both prepared and unprepared lwt statements handle
`bounce_to_shard` messages correctly in such scenario.
Fixes: #8604
Tests: unit(dev, debug)
NOTE: the patchset uses `query_options` as a container for
cached values. This doesn't look clean and `service::query_state`
seems to be a better place to store them. But it's not
forwarded to most of the CQL code and would mean that a huge number
of places would have to be amended.
The series presents a trade-off to avoid forwarding `query_state`
everywhere (but maybe it's the thing that needs to be done, nonetheless).
"
* 'lwt_bounce_to_shard_cached_fn_v6' of https://github.com/ManManson/scylla:
cql-pytest: add a test for non-pure CQL functions
cql3: cache function calls evaluation for non-deterministic functions
cql3: rename `variable_specifications` to `prepare_context`
And reuse these values when handling `bounce_to_shard` messages.
Otherwise such a function (e.g. `uuid()`) can yield a different
value when a statement re-executed on the other shard.
It can lead to an infinite number of `bounce_to_shard` messages
sent in case the function value is used to calculate partition
key ranges for the query. Which, in turn, will cause crashes
since we don't support bouncing more than one time and the second
hop will result in a crash.
Caching works only for LWT statements and only for the function
calls that affect partition key range computation for the query.
`variable_specifications` class is renamed to `prepare_context`
and generalized to record information about each `function_call`
AST node and modify them, as needed:
* Check whether a given function call is a part of partition key
statement restriction.
* Assign ids for caching if above is true and the call is a part
of an LWT statement.
There is no need to include any kind of statement identifier
in the cache key since `query_options` (which holds the cache)
is limited to a single statement, anyway.
Note that `function_call::raw` AST nodes are not created
for selection clauses of a SELECT statement hence they
can only accept only one of the following things as parameters:
* Other function calls.
* Literal values.
* Parameter markers.
In other words, only parameters that can be immediately reduced
to a byte buffer are allowed and we don't need to handle
database inputs to non-pure functions separately since they
are not possible in this context. Anyhow, we don't even have
a single non-pure function that accepts arguments, so precautions
are not needed at the moment.
Tests: unit(dev, debug)
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
After subscription management was moved onto controller level
a bunch of code can be dropped:
- passing migration notifier beyond controller
- event_notifier's _stopped bit
- event_notifier .stop() method
- event_notifier empty constructor and destrictor
- generic_server's on_stop virtual method
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
There's a migration notifier that's carried through cql_server
_just_ to let event-notifier (un)subscribe on it. Also there's
a call for global storage-service in there which will need to
be replaced with yet another pass-through argument which is not
great.
It's easier to establish this subscription outside of cql_server
like it's currently done for proxy and sl-manager. In case of
cql_server the "outside" is the controller.
This patch just moves the subscription management from cql_server
to controller, next two patches will make more use of this change.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Both controller and server only need database to get config from.
Since controller creation only happens in main() code which has the
config itself, we may remove database mentioning from transport.
Previous attempt was not to carry the config down to the server
level, but it stepped on an updateable_value landmine -- the u._v.
isn't copyable cross-shard (despite the docs) and to properly
initialize server's max_concurrent_requests we need the config's
named_value member itself.
The db::config that flies through the stack is const reference, but
its named_values do not get copied along the way -- the updateable
value accepts both references and const references to subscribe on.
tests: start-stop in debug mode
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20210607135656.18522-1-xemul@scylladb.com>
This commit implements the following overload prevention heuristics:
if the admission queue becomes full, a timer is armed for 50ms.
If any of the ongoing requests finishes, the timer is disarmed,
but if that doesn't happen, the server goes into shedding mode,
which means that it reads new requests from the socket and immediately
drops them until one of the ongoing requests finishes.
This heuristics is not recommended for OLAP workloads,
so it is applied only if the session declared itself as
interactive (via service level's workload_type parameter).
storage_proxy.hh is huge and includes many headers itself, so
remove its inclusions from headers and re-add smaller headers
where needed (and storage_proxy.hh itself in source files that
need it).
Ref #1.
The cql_server and redis_server share the same ancestor of do_accepts().
Let's pull up the cql_server version of do_accept() (that has more
functionality) to generic_server::server and use it in the redis_server
too.
Pull up the cql_server process() to base class and convert redis_server
to use it.
Please note that this fixes EPIPE and connection reset issue in the
Redis server, which was fixed in the CQL server in commit 1a8630e6a
("transport: silence "broken pipe" and "connection reset by peer"
errors").
The cql_server and redis_server both have the same "_stopped" and
"_connections_list" member variables. Pull them up to the
generic_server::server base class.
The cql_server and redis_server classes have a maybe_idle() method,
which sets the _all_connections_stopped promise if server wants to stop
and can be stopped. Pull up the duplicated code to
generic_server::server class.
Both cql_server::connection and redis_server::connection inherit
boost::intrusive::list_base_hook<>, so let's pull up that to the
generic_server::connection class that both inherit.
This patch moves the duplicated connection::shutdown() method to to a
new generic_server::connection base class that is now inherited by
cql_server and redis_server.
The cql_server and alternator both need the limiter, so
patch them to stop using storage service's one and use
the main-local one.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The cql_server() need to get the memory limiter semaphore
from local storage service instance. To make this happen
a callback in introduced on the config structure. The same
can be achieved in a simler manner -- by providing the
local storage service instances directly.
Actually, the storage service will be removed in further
patches from this place, so this patch is mostly to get
rid of the callback from the config.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
On start the transport controller keeps the storage service
on server config's lambda just to let the server grab a
database config option.
The same can be achieved by passing the sharded database
reference to sharded<server>::start, so that each server
instance get local database with config.
As an nice side effect transport::server's config looks
more like a config with simple values and without methods
and/or lambdas on board.
tests: unit(dev)
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20210205175611.13464-1-xemul@scylladb.com>
As reproduced in cql-pytest/test_json.py and reported in issue #7911,
failing fromJson() calls should return a FUNCTION_FAILURE error, but
currently produce a generic SERVER_ERROR, which can lead the client
to think the server experienced some unknown internal error and the
query can be retried on another server.
This patch adds a new cassandra_exception subclass that we were missing -
function_execution_exception - properly formats this error message (as
described in the CQL protocol documentation), and uses this exception
in two cases:
1. Parse errors in fromJson()'s parameters are converted into a
function_execution_exception.
2. Any exceptions during the execute() of a native_scalar_function_for
function is converted into a function_execution_exception.
In particular, fromJson() uses a native_scalar_function_for.
Note, however, that functions which already took care to produce
a specific Cassandra error, this error is passed through and not
converted to a function_execution_exception. An example is
the blobAsText() which can return an invalid_request error, so
it is left as such and not converted. This also happens in Cassandra.
All relevant tests in cql-pytest/test_json.py now pass, and are
no longer marked xfail. This patch also includes a few more improvements
to test_json.py.
Fixes#7911
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210118140114.4149997-1-nyh@scylladb.com>
This change adds tracking of all the CQL errors that can be
raised in response to a CQL message from a client, as described
in the CQL v4 protocol and with Scylla's CDC_WRITE_FAILUREs
included.
Fixes#5859Closes#7604
This change adds metrics for counting request message types
listed in the CQL v.4 spec under section 4.1
(https://github.com/apache/cassandra/blob/trunk/doc/native_protocol_v4.spec).
To organize things properly, we introduce a new cql_server::transport_stats
object type for aggregating the message and server statistics.
Fixes#4888Closes#7574
This patch fills the following columns in `system.clients` table:
* `connection_stage`
* `driver_name`
* `driver_version`
* `protocol_version`
It also improves:
* `client_type` - distinguishes cql from thrift just in case
* `username` - now it displays correct username iff `PasswordAuthenticator` is configured.
What is still missing:
* SSL params (I'll happily get some advice here)
* `hostname` - I didn't find it in tested drivers
Refs #6946Closes#7349
* github.com:scylladb/scylla:
transport: Update `connection_stage` in `system.clients`
transport: Retrieve driver's name and version from STARTUP message
transport: Notify `system.clients` about "protocol_version"
transport: On successful authentication add `username` to system.clients
After adding a new node to the cluster, Scylla sends a NEW_NODE event
to CQL clients. Some clients immediately try to connect to the new node,
however it fails as the node has not yet started listening to CQL
requests.
In contrast, Apache Cassandra waits for the new node to start its CQL
server before sending NEW_NODE event. In practice this means that
NEW_NODE and UP events will be sent "jointly" after new node is UP.
This change is implemented in the same manner as in Apache Cassandra
code.
Fixes#7301.
Closes#7306
The username becomes known in the course of resolving challenges
from `PasswordAuthenticator`. That's why username is being set on
successful authentication; until then all users are "anonymous".
Meanwhile, `AllowAllAuthenticator` (the default) does not request
username, so users logged with it will remain as "anonymous" in
`system.clients`.
Shuffling of code was necessary to unify existing infrastructure
for INSERTing entries into `system.clients` with later UPDATEs.
Recently, the cql_server_config::max_concurrent_requests field was
changed to be an updateable_value, so that it is updated when the
corresponding option in Scylla's configuration is live-reloaded.
Unfortunately, due to how cql_server is constructed, this caused
cql_server instances on all shards to store an updateable_value which
pointed to an updateable_value_source on shard 0. Unsynchronized
cross-shard memory operations ensue.
The fix changes the cql_server_config so that it holds a function which
creates an updateable_value appropriate for the given shard. This
pattern is similar to another, already existing option in the config:
get_service_memory_limiter_semaphore.
This fix can be reverted if updateable_value becomes safe to use across
shards.
Tests: unit(dev)
Fixes: #7310
It's not realistic for a shard to have over 4 billion concurrent
requests, so this value can be safely represented in 32 bits.
Also, since the current concurrency limit is represented in uint32_t,
it makes sense for these two to have matching types.
This configuration entry is expected to be used as a quick fix
for an overloaded node, so it should be possible to reload this value
without having to restart the server.
The newly introduced parameter - max_concurrent_requests_per_shard
- can be used to limit the number of in-flight requests a single
coordinator shard can handle. Each surplus request will be
immediately refused by returning OverloadedException error to the client.
The default value for this parameter is large enough to never
actually shed any requests.
Currently, the limit is only applied to CQL requests - other frontends
like alternator and redis are not throttled yet.
The new port is configurable from scylla.yaml and defaults to 19042
(unencrypted, unless client configures encryption options and omits
`native_shard_aware_transport_port_ssl`).
Two "SUPPORTED" tags are added: "SCYLLA_SHARD_AWARE_PORT" and
"SCYLLA_SHARD_AWARE_PORT_SSL". For compatibility,
"SCYLLA_SHARDING_ALGORITHM" is still kept.
Fixes#5239
This removes the need to include reactor.hh, a source of compile
time bloat.
In some places, the call is qualified with seastar:: in order
to resolve ambiguities with a local name.
Includes are adjusted to make everything compile. We end up
having 14 translation units including reactor.hh, primarily for
deprecated things like reactor::at_exit().
Ref #1
