We switched to using v3 schema tables (in system_schema keyspace) in
2017, in 9eb91bc30b.
So no system should have the old schema any more.
No need to run legacy_schema_migrator on boot.
Closesscylladb/scylladb#27420
After previous commits, we can drop entire task's state and replace it
with single boolean flag, which determines if a task was aborted.
Once a task was aborted, it cannot get resurrected to a normal state.
use utils::chunked_vector instead of std::vector to store cdc stream
sets for tablets.
a cdc stream set usually represents all streams for a specific table and
timestamp, and has a stream id per each tablet of the table. each stream
id is represented by 16 bytes. thus the vector could require quite large
contiguous allocations for a table that has many tablets. change it to
chunked_vector to avoid large contiguous allocations.
Fixesscylladb/scylladb#26791Closesscylladb/scylladb#26792
when loading CDC streams metadata for tablets from the tables, read only
new entries from the history table instead of reading all entries. This
improves the CDC metadata reloading, making it more efficient and
predictable.
the CDC metadata is loaded as part of group0 reload whenever the
internal CDC tables are modified. on tablet split / merge, we create a
new CDC timestamp and streams by writing them to the cdc_streams_history
table by group0 operation, and when it's applied we reload the in-memory
CDC streams map by reading from the tables and constructing the updated map.
Previously, on every update, we would read the entire
cdc_streams_history entries for the changed table, constructing all its
streams and creating a new map from scratch.
We improve this now by reading only new entries from cdc_streams_history
and append them to the existing map. we can do this because we only
append new entries to cdc_streams_history with higher timestamp than all
previous entries.
This makes this reloading more efficient and predictable, because
previously we would read a number of entries that depends on the number
of tablets splits and merges, which increases over time and is
unbounded, whereas now we read only a single stream set on each update.
Fixesscylladb/scylladb#26732
This commit extends sytem.scylla_local table with an additional
key/value pair that can be used later in this patch series to
keep an information that `sl:driver` was already created. The purpose
of storing this information is to ensure that `sl:driver` is
not recreated after being intentionally removed.
A new mutation is included in `register_raft_pull_snapshot` to keep
`service_level_driver_created` in state machine shapshot, which is
required for proper propagation of the value when a new node is added
to the cluster.
Refs: scylladb/scylladb#24411
The directory utils/ is supposed to contain general-purpose utility
classes and functions, which are either already used across the project,
or are designed to be used across the project.
This patch moves 8 files out of utils/:
utils/advanced_rpc_compressor.hh
utils/advanced_rpc_compressor.cc
utils/advanced_rpc_compressor_protocol.hh
utils/stream_compressor.hh
utils/stream_compressor.cc
utils/dict_trainer.cc
utils/dict_trainer.hh
utils/shared_dict.hh
These 8 files together implement the compression feature of RPC.
None of them are used by any other Scylla component (e.g., sstables have
a different compression), or are ready to be used by another component,
so this patch moves all of them into message/, where RPC is implemented.
Theoretically, we may want in the future to use this cluster of classes
for some other component, but even then, we shouldn't just have these
files individually in utils/ - these are not useful stand-alone
utilities. One cannot use "shared_dict.hh" assuming it is some sort of
general-purpose shared hash table or something - it is completely
specific to compression and zstd, and specifically to its use in those
other classes.
Beyond moving these 8 files, this patch also contains changes to:
1. Fix includes to the 5 moved header files (.hh).
2. Fix configure.py, utils/CMakeLists.txt and message/CMakeLists.txt
for the three moved source files (.cc).
3. In the moved files, change from the "utils::" namespace, to the
"netw::" namespace used by RPC. Also needed to change a bunch
of callers for the new namespace. Also, had to add "utils::"
explicitly in several places which previously assumed the
current namespace is "utils::".
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closesscylladb/scylladb#25149
When the view builder starts to build a new view, each shard registers
itself by writing the shard id and current token to the
scylla_views_builds_in_progress table.
Previously, this happened independently by each shard. We change it now
to register all shards "atomically" - when a shard registers itself, it
also registers all other shards with an empty status, if they aren't
registered yet. This ensures that we don't have a partial state in the
table where only some of the shards are registered, but we always have a
status for all shards.
The reason we want to register all shards atomically is that if it
happens that only some of the shards were registered, then we restart
and load the status from table, this doesn't work well for multiple
reasons.
One example is that to know how many shards we had previously, we take
the maximum shard id we see in the table. If it's different than the
current shard count, we will execute the reshard code. But of course, if
the last shard is missing from the table because it didn't register
itself, this calculation will be wrong, and we can't know the previous
number of shards.
This is a problem because suppose we have two shards, and shard 0
finished building the view but shard 1 didn't start. When we come up, we
will think that previously we had only a single shard and it completed
building everything, when in fact we built only half the view
approximately. The problem is that we don't have enough information in
the tables to know that.
There are additional problems related to reshard. In the reshard
function, whether it is executed because we actually do node reshard or
because we calculated the wrong number of previous shards, if the status
of some shard is missing then the calculation of new ranges will be
wrong. When some shard didn't make progress we should start building the
view from scratch. However, this doesn't happen if we don't have a
status for the shard, because the code looks only for shards that have a
status. In effect, this shard is considered complete even though it
didn't start. This could cause the view building to get stuck or
complete without building all tokens ranges.
By registering all shards atomically, this should solve the above
problems because we will always have statuses for all shards.
Fixesscylladb/scylladb#22989
The latter is recommended in seastar, and the former was left as
compatibility alias. Latest seastar explicitly marks it as deprecated so
once the submodule is updated, compilation logs will explode.
Most of the patch is generated with
for f in $(git grep -l '\<distributed<[A-Za-z0-9:_]*>') ; do sed -e 's/\<distributed<\([A-Za-z0-9:_]*\)>/sharded<\1>/g' -i $f; done
for f in $(git grep -l distributed.hh); do sed -e 's/distributed.hh/sharded.hh/' -i $f ; done
and a small manual change in test/perf/perf.hh
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closesscylladb/scylladb#26136
This commit extends sytem.scylla_local table with an additional
key/value pair that can be used later in this patch series to
keep an information that `sl:driver` was already created. The purpose
of storing this information is to ensure that `sl:driver` is
not recreated after being intentionally removed.
A new mutation is included in `register_raft_pull_snapshot` to keep
`service_level_driver_created` in state machine shapshot, which is
required for proper propagation of the value when a new node is added
to the cluster.
Refs: scylladb/scylladb#24411
Add new group0-based tables in system keyspace to be used for cdc with tablets:
* cdc_streams_state - describing "base" state of CDC streams for each
table - an initial timestamp and a stream set.
* cdc_streams_history - describing following committed stream sets by
diffs (opened / closed streams) from the previous set.
As requested in #22120, moved the files and fixed other includes and build system.
Moved files:
- query.cc
- query-request.hh
- query-result.hh
- query-result-reader.hh
- query-result-set.cc
- query-result-set.hh
- query-result-writer.hh
- query_id.hh
- query_result_merger.hh
Fixes: #22120
This is a cleanup, no need to backport
Closesscylladb/scylladb#25105
Fixes#25683
Once a table drop is complete, there should be no reason to retain
truncation records for it, as any replay should skip mutations
anyway (no CF), and iff we somehow resurrect a dropped table,
this replay-resurrected data is the least problem anyway.
Adds a prune phase to the startup drop_truncation_rp_records run,
which ignores updating, and instead deletes records for non-existant
tables (which should patch any existing servers with lingering data
as well).
Also does an explicit delete of records on actual table DROP, to
ensure we don't grow this table more than needed even in long
uptime nodes.
Small unit test included.
Closesscylladb/scylladb#25699
The gossiper can call `storage_service::on_change` frequently (see scylladb/scylla-enterprise#5613), which may cause high CPU load and even trigger OOMs or related issues.
This PR adds a temporary cache for `system.peers` to resolve host_id -> ip without hitting storage on every call. The cache is short-lived to handle the unlikely case where `system.peers` is updated directly via CQL.
This is a temporary fix; a more thorough solution is tracked in https://github.com/scylladb/scylladb/issues/25620.
Fixesscylladb/scylladb#25660
backport: this patch needs to be backported to all supported versions (2025.1/2/3).
Closesscylladb/scylladb#25658
* github.com:scylladb/scylladb:
storage_service: move get_host_id_to_ip_map to system_keyspace
system_keyspace: use peers cache in get_ip_from_peers_table
storage_service: move get_ip_from_peers_table to system_keyspace
Reimplemented the function to use the peers cache. It could be replaced
with get_ip_from_peers_table, but that would create a coroutine frame for
each call.
The storage_service::on_change method can be called quite often
by the gossiper, see scylladb/scylla-enterprise#5613. In this commit
we introduce a temporal cache for system.peers so that we don't have
to go to the storage each time we need to resolve host_id -> ip.
We keep the cache only for a small amount of time to handle the
(unlikely) scenario when the user wants to update system.peers table
from CQL.
Fixesscylladb/scylladb#25660
We plan to add a cache to get_ip_from_peers_table in upcoming commits.
It's more convenient to do this from system_keyspace, since the only two
methods that mutate system.peers (remove_endpoint and update_peers_info)
are already there.
The view building coordinator will be building all views
of one base table at a time.
Select first available base table as currently processing base
and save this information to `system.scylla_local`.
Until now, all changes to `system.view_build_status_v2` were made from
view.cc and the file contained all of the helper methods.
This commit introduces a `build_status` enum class to avoid using
hardcoded strings and extracts the helper methods to `system_keyspace`
class, so they can be later used by the view building coordinator.
Allow applying writes in the form of mutations directly to the keyspace.
Allows lower-level mutation API to build writes. Advantageous if writes
can contain large cells that would otherwise possibly cause large
allocation warnings if used via the internal CQL API.
To serve as a place to store corrupt mutation fragments. These fragments
cannot be written to sstables, as they would be spread around by
compaction and/or repair. They even might make parsing the sstable
impossible. So they are stored in this special table instead, kept
around to be inspected later and possibly restored if possible.
topology_request table has a filed to hold a request type, but
currently it can hold only per node requests. This patch makes it
possible to store global request types there as well.
Currently parameters to alter table global topology command are stored
in static column in the topology table, but this way there can be only one
outstanding alter table request. This patch moves the parameters to
the topology_request table where parameters are stored per request.
Move the compaction_history_entry struct to a seperate file. The intent
of this change is to later re-use it in scylla-nodetool as it currently
defines its own structure that is very similar.
Since the number of statistics inserted into compaction_history
table grows in time, the number of parameters in the method
update_compaction_history grows as well.
So instead, let's re-use the already existing compaction_history_entry
structure to populate data from the compaction_manager to the
system table.
Changing DC or rack on a node which was already bootstrapped is, in
case of vnodes, very unsafe (almost guaranteed to cause data loss or
unavailability), and is outright not supported if the cluster has
a tablet-backed keyspaces. Moreover, the possibility of doing that
makes it impossible to uphold some of the invariants promised by
the RF-rack-valid flag, which is eventually going to become
unconditionally enabled.
Get rid of the above problems by removing the possibility of changing
the DC / rack of a node. A node will now fail to start if its snitch
reports a different DC or rack than the one that was reported during the
first boot.
Fixes: scylladb/scylladb#23278
"
The series makes endpoint state map in the gossiper addressable by host
id instead of ips. The transition has implication outside of the
gossiper as well. Gossiper based topology operations are affected by
this change since they assume that the mapping is ip based.
On wire protocol is not affected by the change as maps that are sent by
the gossiper protocol remain ip based. If old node sends two different
entries for the same host id the one with newer generation is applied.
If new node has two ids that are mapped to the same ip the newer one is
added to the outgoing map.
Interoperability was verified manually by running mixed cluster.
The series concludes the conversion of the system to be host id based.
"
* 'gleb/gossipper-endpoint-map-to-host-id-v2' of github.com:scylladb/scylla-dev:
gossiper: make examine_gossiper private
gossiper: rename get_nodes_with_host_id to get_node_ip
treewide: drop id parameter from gossiper::for_each_endpoint_state
treewide: move gossiper to index nodes by host id
gossiper: drop ip from replicate function parameters
gossiper: drop ip from apply_new_states parameters
gossiper: drop address from handle_major_state_change parameter list
gossiper: pass rpc::client_info to gossiper_shutdown verb handler
gossiper: add try_get_host_id function
gossiper: add ip to endpoint_state
serialization: fix std::map de-serializer to not invoke value's default constructor
gossiper: drop template from wait_alive_helper function
gossiper: move get_supported_features and its users to host id
storage_service: make candidates_for_removal host id based
gossiper: use peers table to detect address change
storage_service: use std::views::keys instead of std::views::transform that returns a key
gossiper: move _pending_mark_alive_endpoints to host id
gossiper: do not allow to assassinate endpoint in raft topology mode
gossiper: fix indentation after previous patch
gossiper: do not allow to assassinate non existing endpoint
Adds a helper method which queries the creation timestamp
of a given dict in `system.dicts`.
We will later use the age of the current SSTable compression dict
to decide if another training should be done already.
When a table is dropped, its corresponding dictionary in `system.dicts`
-- if any -- should be deleted, otherwise it will remain forever as
garbage.
This commit implements such cleanup.
Extend the `system.dicts` helper for querying and modifying
`system.dicts` with an ability to use names other than "general".
We will use that in later commits to publish dictionaries for SSTable compression.
Before this patch, `system.dicts` contains only one dictionary, for RPC
compression, with the fixed name "general".
In later parts of this series, we will add more dictionaries to
system.dicts, one per table, for SSTable compression.
To enable that, this patch adjusts the callback mechanism for group0's `write_mutations`
command, so that the mutation callbacks for group0-managed tables can see which
partition keys were affected. This way, the callbacks can query only the
modified partitions instead of doing a full scan. (This is necessary to
prevent quadratic behaviours.)
For now, only the `system.dicts` callback uses the partition keys.
In the current scenario, topology_change_kind variable, was been handled using
_manage_topology_change_kind_from_group0 variable. This method was brittle
and had some bugs(e.g. for restart case, it led to a time gap between group0
server start and topology_change_kind being managed via group0)
Post _manage_topology_change_kind_from_group0 removal, careful management of
topology_change_kind variable was needed for maintaining correct
topology_change_kind in all scenarios. So this PR also performs a refactoring
to populate all init data to system tables even before group0 creation(via
raft_initialize_discovery_leader function). Now because raft_initialize_discovery_leader
happens before the group 0 creation, we write mutations directly to system
tables instead of a group 0 command. Hence, post group0 creation, the node
can read the correct values from system tables and correct values are
maintained throughout.
Added a new function initialize_done_topology_upgrade_state which takes
care of updating the correct upgrade state to system tables before starting
group0 server. This ensures that the node can read the correct values from
system tables and correct values are maintained throughout.
By moving raft_initialize_discovery_leader logic to happen before starting
group0 server, and not as group0 command post server start, we also get rid
of the potential problem of init group0 command not being the 1st command on
the server. Hence ensuring full integrity as expected by programmer.
Fixes: scylladb/scylladb#21114
node_ops_virtual_task does not filter the entries of system.topology_request
and so it creates statuses of operations that aren't node ops.
Filter the entries used by node_ops_virtual_task. With this change, the status
of a bootstrap of the first node will not be visible.
Fixes: https://github.com/scylladb/scylladb/issues/22008.
Needs backport to 6.2 that introduced node_ops_virtual_task
Closesscylladb/scylladb#22009
* github.com:scylladb/scylladb:
test: truncate the table before node ops task checks
node_ops: rename a method that get node ops entries
node_ops: filter topology_requests entries
Adds a new system table which will act as the medium for distributing
compression dictionaries over the cluster.
This table will be managed by Raft (group 0). It will be hooked up to it in
follow-up commits.
This depends on the previous change to the schema_builder
which makes version computation depend on definition only
instead of being new time uuid.
This way we avoid the possibility for a common mistake
when schema of a system table is extended but we forget
to bump up its version passed to .with_version().
Today, the system.sstables schema uses string as partition key. Callers,
in turn, use table's datadir value to reference entries in it. That's
wrong, S3-backed sstables don't have any local paths to work with. The
table's ID is better in this role.
This patch only changes the field type to be table_id and fixes the
callers to provide one. In particular, see init_table_storage() change
-- instead of generating a datadir string, it sets table.id() as the
options' location. Other fixed places are tests. Internally, this id
value is propagated via s3_storage::owner() method, that's fixed as
well.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Add an intermediate phase to the view builder migration to v2 where we
write to both the old and new table in order to not lose writes during
the migration.
We add an additional view builder version v1_5 between v1 and v2 where
we write to both tables. We perform a barrier before moving to v2 to
ensure all the operations to the old table are completed.
