When a node joins this feature (which it does immediately when upgrading
to a version that has this commit), it says: "I understand the new
generation storage format and the new identifier format". Thus, when the
feature becomes enabled - after all nodes have joined it - it means that
it's safe to create new generations using these new storage/ID formats.
To control the transition to the data variant of range scans. As there
is a difference in how the data and mutation variants calculate pages
sizes, the transition to the former has to happen in a controlled
manner, when all nodes in the cluster support it, to avoid artificial
differences in page content and subsequently triggering false-positive
read repair.
Add new alternator-streams experimental flag for
alternator streams control.
CDC becomes GA and won't be guarded by an experimental flag any more.
Alternator Streams stay experimental so now they need to be controlled
by their own experimental flag.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
Add new correct_idx_token_in_secondary_index feature, which will be used
to determine if all nodes in the cluster support new
token_column_computation. This column computation will replace
legacy_token_column_computation in secondary indexes, which was
incorrect as this column computation produced values that when compared
with unsigned comparison (CQL type bytes comparison) resulted in
different ordering than token signed comparison. See issue:
https://github.com/scylladb/scylla/issues/7443
This feature will ensure that caching can be switched
off per table only after the whole cluster supports it.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
This new feature is required because we now allow
setting partitioner per table. This will influence
the digest of table schema so we must not include
partitioner name into the digest unless we know that
the whole cluster already supports per table partitioners.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
In test_services.cc there is
gms::feature_service test_feature_service;
And the feature_service constructor has
, _lwt_feature(*this, features::LWT)
But features::LWT is a global sstring constructed in another file.
Solve the problem by making the feature strings constexpr
std::string_view.
I found the issue while trying to benchmark the std::string switch.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
Acked-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20200309225749.36661-1-espindola@scylladb.com>
And leave some temporary storage_service->feature links. The plan
is to make every subsystem that needs storage_service for features
stop doing so and switch on the feature_service.
The feature_service is the service w/o any dependencies, it will be
freed last, thus making the service dependency tree be a tree,
not a graph with loops.
While at it -- make all const-s not have _FEATURE suffix (now there
are both options) and const-qualify cluster_supports_lwt().
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
It can be invoked with a lambda without the ceremony of creating a
class deriving from gms::feature::listener.
The reutrned registration object controls listener's scope.
Feature lifetime is tied to storage_service lifetime, but features are now managed
by gossip. To avoid circular dependency, add a new feature_service service to manage
feature lifetime.
To work around the problem, the current code re-initializes features after
gossip is initialized. This patch does not fix this problem; it only makes it
possible to solve it by untyping features from gossip.
Add the helper function to enable the a feature and log the feature is
enabled.
When a feature is enabled, we see
INFO 2016-12-15 11:29:32,443 [shard 0] gossip - Feature LARGE_PARTITIONS is enabled
INFO 2016-12-15 11:29:32,443 [shard 0] gossip - Feature RANGE_TOMBSTONES is enabled
in the log.
This class encapsulates the waiting for a cluster feature. A feature
object is registered with the gossiper, which is responsible for later
marking it as enabled.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
