The mechanics of the restore is like this
- A /storage_service/tablets/restore API is called with (keyspace, table, endpoint, bucket, manifests) parameters
- First, it populates the system_distributed.snapshot_sstables table with the data read from the manifests
- Then it emplaces a bunch of tablet transitions (of a new "restore" kind), one for each tablet
- The topology coordinator handles the "restore" transition by calling a new RESTORE_TABLET RPC against all the current tablet replicas
- Each replica handles the RPC verb by
- Reading the snapshot_sstables table
- Filtering the read sstable infos against current node and tablet being handled
- Downloading and attaching the filtered sstables
This PR includes system_distributed.snapshot_sstables table from @robertbindar and preparation work from @kreuzerkrieg that extracts raw sstables downloading and attaching from existing generic sstables loading code.
This is first step towards SCYLLADB-197 and lacks many things. In particular
- the API only works for single-DC cluster
- the caller needs to "lock" tablet boundaries with min/max tablet count
- not abortable
- no progress tracking
- sub-optimal (re-kicking API on restore will re-download everything again)
- not re-attacheable (if API node dies, restoration proceeds, but the caller cannot "wait" for it to complete via other node)
- nodes download sstables in maintenance/streaming sched gorup (should be moved to maintenance/backup)
Other follow-up items:
- have an actual swagger object specification for `backup_location`
Closes#28436Closes#28657Closes#28773Closesscylladb/scylladb#28763
* github.com:scylladb/scylladb:
test: Add test for backup vs migration race
test: Restore resilience test
sstables_loader: Fail tablet-restore task if not all sstables were downloaded
sstables_loader: mark sstables as downloaded after attaching
sstables_loader: return shared_sstable from attach_sstable
db: add update_sstable_download_status method
db: add downloaded column to snapshot_sstables
db: extract snapshot_sstables TTL into class constant
test: Add a test for tablet-aware restore
tablets: Implement tablet-aware cluster-wide restore
messaging: Add RESTORE_TABLET RPC verb
sstables_loader: Add method to download and attach sstables for a tablet
tablets: Add restore_config to tablet_transition_info
sstables_loader: Add restore_tablets task skeleton
test: Add rest_client helper to kick newly introduced API endpoint
api: Add /storage_service/tablets/restore endpoint skeleton
sstables_loader: Add keyspace and table arguments to manfiest loading helper
sstables_loader_helpers: just reformat the code
sstables_loader_helpers: generalize argument and variable names
sstables_loader_helpers: generalize get_sstables_for_tablet
sstables_loader_helpers: add token getters for tablet filtering
sstables_loader_helpers: remove underscores from struct members
sstables_loader: move download_sstable and get_sstables_for_tablet
sstables_loader: extract single-tablet SST filtering
sstables_loader: make download_sstable static
sstables_loader: fix formating of the new `download_sstable` function
sstables_loader: extract single SST download into a function
sstables_loader: add shard_id to minimal_sst_info
sstables_loader: add function for parsing backup manifests
split utility functions for creating test data from database_test
export make_storage_options_config from lib/test_services
rjson: Add helpers for conversions to dht::token and sstable_id
Add system_distributed_keyspace.snapshot_sstables
add get_system_distributed_keyspace to cql_test_env
code: Add system_distributed_keyspace dependency to sstables_loader
storage_service: Export export handle_raft_rpc() helper
storage_service: Export do_tablet_operation()
storage_service: Split transit_tablet() into two
tablets: Add braces around tablet_transition_kind::repair switch
`storage_service::get_tablets_migration_status()` returns the
keyspace-level migration status, indicating whether migration has not
started, is in progress, or has completed, and for migrating keyspaces
also returns per-node migration statuses. Rename it to
`get_tablets_migration_status_with_node_details()` and introduce a new
`get_tablets_migration_status()` that returns only the keyspace-level
status.
This prepares the function for reuse in the next patches, which will add
a virtual task for vnodes-to-tablets migrations. Several task-manager
paths will only need the keyspace-level migration state, not per-node
information.
Signed-off-by: Nikos Dragazis <nikolaos.dragazis@scylladb.com>
Using a string was sufficient while this status was only exposed through
the REST API, but the next patches will also consume it internally.
Use an enum for the internal representation and convert it back to the
existing string values in the REST API.
Signed-off-by: Nikos Dragazis <nikolaos.dragazis@scylladb.com>
ScyllaDB uses estimated_histogram in many places.
We already have a more efficient alternative: estimated_histogram_with_max. It is both CPU- and
memory-efficient, and it can be exported as Prometheus native histograms.
Its main limitation (which also has benefits) is that the bucket layout is fixed at compile time, so
histograms with different configurations cannot be mixed.
The end goal is to replace all uses of estimated_histogram in the codebase.
That migration requires a few small API adjustments, so it is done in steps.
This PR replaces estimated_histogram for CAS contention.
The PR includes a patch that adds functionality to the base approx_exponential_histogram, which will be used by the API.
The specific histograms are defined in a single place and cover the range 1-100; this makes future changes easy.
**New feature, no need to backport**
Closesscylladb/scylladb#29017
* github.com:scylladb/scylladb:
storage_proxy: migrate CAS contention histograms to estimated_histogram_with_max
estimated_histogram.hh: Add bucket offset and count to approx_exponential_histogram
Config is reloaded from SIGHUP on shard 0 and broadcast to all shards
under a write lock. REST API callers reading find_config_id acquire a
read lock via value_as_json_string_for_name() and are guaranteed a
consistent snapshot even when a reload is in progress.
The new cluster-wide tablets restore API is going to be asynchronous,
just like existing node-local one is. For that the task_manager tasks
will be used.
This patch adds a skeleton for tablets-restore task with empty run
method. Next patches will populate it.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Withdrawn from #28701. The endpoint implementation from the PR is going
to be reworked, but the swagger description and set/unset placeholders
are very useful.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Co-authored-by: Ernest Zaslavsky <ernest.zaslavsky@scylladb.com>
This series fixes two related inconsistencies around secondary-index
names.
1. `DESCRIBE INDEX ... WITH INTERNALS` returned the backing
materialized-view name in the `name` column instead of the logical
index name.
2. The snapshot REST API accepted backing table names for MV-backed
secondary indexes, but not the logical index names exposed to users.
The snapshot side now resolves logical secondary-index names to backing
table names where applicable, reports logical index names in snapshot
details, rejects vector index names with HTTP 400, and keeps multi-keyspace
DELETE atomic by resolving all keyspaces before deleting anything.
The tests were also extended accordingly, and the snapshot test helper
was fixed to clean up multi-table snapshots using one DELETE per table.
Fixes: SCYLLADB-1122
Minor bugfix, no need to backport.
Closesscylladb/scylladb#29083
* github.com:scylladb/scylladb:
cql3: fix DESCRIBE INDEX WITH INTERNALS name
test: add snapshot REST API tests for logical index names
test: fix snapshot cleanup helper
api: clarify snapshot REST parameter descriptions
api: surface no_such_column_family as HTTP 400
db: fix clear_snapshot() atomicity and use C++23 lambda form
db: normalize index names in get_snapshot_details()
db: add resolve_table_name() to snapshot_ctl
Document the current /storage_service/snapshots behavior
more accurately.
For DELETE, cf is a table filter applied independently
in each keyspace listed in kn. If cf is omitted or
empty, snapshots for all tables are eligible, and
secondary indexes can be addressed by their logical
index name.
Snapshot requests that name a non-existent table or a
non-snapshotable logical index currently surface an
internal server error.
Translate no_such_column_family into a bad request so
callers get a client-facing error that matches the
invalid input.
Replace strict case-sensitive '== "True"' check with strcasecmp(..., "true")
so that Python's str(True) -> "True" is properly recognized. Accepts any
case variation of "true" ("True", "TRUE", etc.), with empty string
defaulting to false.
Maintains backward compatibility with out-of-tree tests that rely on
Python's bool stringification.
The goal is to reduce the number of distinct ways API handlers use to
convert string http query parameters into bool variables. This place is the
only one that simply compares param to "True".
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Closesscylladb/scylladb#29236
The endpoint in question has some places worth fixing, in particular
- the keyspace parameter is not validated
- the validated table name is resolved into table_id, but the id is unused
- two ugly static helpers to stream obtained token ranges into json
Improving the API code flow, not backporting
Closesscylladb/scylladb#29154
* github.com:scylladb/scylladb:
api: Inline describe_ring JSON handling
storage_service: Make describe_ring_for_table() take table_id
If the keyspace is migrating, it reports the intended and actual storage
mode for each node.
Signed-off-by: Nikos Dragazis <nikolaos.dragazis@scylladb.com>
The endpoint is the following:
POST /storage_service/vnode_tablet_migrations/keyspaces/{keyspace}/finalization
When called, it issues a `finalize_migration` topology request and waits
for its completion.
Signed-off-by: Nikos Dragazis <nikolaos.dragazis@scylladb.com>
The endpoint is the following:
POST /storage_service/vnode_tablet_migrations/node/storage_mode?intended_mode={tablets,vnodes}
This endpoint is part of the vnodes-to-tablets migration process and
controls a node's intended_storage_mode in system.topology. The storage
mode represents the node-local data distribution model, i.e., how data
are organized across shards. The node will apply the intended storage
mode to migrating tables upon next restart by resharding their SSTables
(either on vnode boundaries if intended_mode=tablets, or with the static
sharder if intended_mode=vnodes).
Note that this endpoint controls the intended_storage_mode of the local
node only. This has the nice benefit that once the API call returns, the
change has not only been committed to group0 but also applied to the
local node's state machine. This guarantees that the change is part of
the node's local copy upon next restart; no additional read barrier is
needed.
Signed-off-by: Nikos Dragazis <nikolaos.dragazis@scylladb.com>
The endpoint is the following:
POST /storage_service/vnode_tablet_migrations/keyspaces/{keyspace}
Its purpose is to start the migration of a whole keyspace from vnodes to
tablets.
When called, Scylla will synchronously create a tablet map for each
table in the specified keyspace. The tablet maps of all tables are
identical and they mirror the vnode layout; they contain one tablet per
vnode and each tablet uses the same replica hosts and token boundaries
as the corresponding vnode.
The only difference from vnodes lies in the sharding approach. Tablets
are assigned to a single shard - using a round-robin strategy in this
patch - whereas vnodes are distributed evenly across all shards. If the
tablet count per shard is low and tablet sizes are uneven, or some
shards have more tablets than others, performance may degrade during the
migration process. For example, a cluster with i8g.48xlarge (192 vCPUs),
256 vnodes per node and RF=3 will have 256 * 3 / 192 vCPUs = 4 tablet
replicas per shard during the migration. One additional tablet or a
double-sized tablet would cause 25% overcommit.
Signed-off-by: Nikos Dragazis <nikolaos.dragazis@scylladb.com>
There are two helpers for describe_ring endpoint. Both can be squashed
together for code brevity.
Also, while at it, the "keyspace" parameter is not properly validated by
the endpoint.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
All callers already have it. It makes no difference for the method
itself with which table identifier to work, but will help to simplify
the flow in API handler (next patch)
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
The endpoint URL remains intact. Having it next to another toppartitions
endpoint (the /column_family/toppartitions one) is natural.
This endpoint only needs sharded<replica::database>&, grabs it from
http_context and doesn't use any other service. In column_family.cc the
database reference is already available as a parameter. Once more user
of http_context.db is gone.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Closesscylladb/scylladb#28996
Introduce an initial and experimental implementation of an alternative log-structured storage engine for key-value tables.
Main flows and components:
* The storage is composed of 32MB files, each file divided to segments of size 128k. We write to them sequentially records that contain a mutation and additional metadata. Records are written to a buffer first and then written to the active segment sequentially in 4k sized blocks.
* The primary index in memory maps keys to their location on disk. It is a B-tree per-table that is ordered by tokens, similar to a memtable.
* On reads we calculate the key and look it up in the primary index, then read the mutation from disk with a single disk IO.
* On writes we write the record to a buffer, wait for it to be written to disk, then update the index with the new location, and free the previous record.
* We track the used space in each segment. When overwriting a record, we increase the free space counter for the segment of the previous record that becomes dead. We store the segments in a histogram by usage.
* The compaction process takes segments with low utilization, reads them and writes the live records to new segments, and frees the old segments.
* Segments are initially "mixed" - we write to the active segment records from all tables and all tablets. The "separator" process rewrites records from mixed segments into new segments that are organized by compaction groups (tablets), and frees the mixed segments. Each write is written to the active segment and to a separator buffer of the compaction group, which is eventually flushed to a new segment in the compaction group.
Currently this mode is experimental and requires an experimental flag to be enabled.
Some things that are not supported yet are strong consistency, tablet migration, tablet split/merge, big mutations, tombstone gc, ttl.
to use, add to config:
```
enable_logstor: true
experimental_features:
- logstor
```
create a table:
```
CREATE TABLE ks.t(pk int PRIMARY KEY, a int, v text) WITH storage_engine = 'logstor';
```
INSERT, SELECT, DELETE work as expected
UPDATE not supported yet
no backport - new feature
Closesscylladb/scylladb#28706
* github.com:scylladb/scylladb:
logstor: trigger separator flush for buffers that hold old segments
docs/dev: add logstor documentation
logstor: recover segments into compaction groups
logstor: range read
logstor: change index to btree by token per table
logstor: move segments to replica::compaction_group
db: update dirty mem limits dynamically
logstor: track memory usage
logstor: logstor stats api
logstor: compaction buffer pool
logstor: separator: flush buffer when full
logstor: hold segment until index updates
logstor: truncate table
logstor: enable/disable compaction per table
logstor: separator buffer pool
test: logstor: add separator and compaction tests
logstor: segment and separator barrier
logstor: separator debt controller
logstor: compaction controller
logstor: recovery: recover mixed segments using separator
logstor: wait for pending reads in compaction
logstor: separator
logstor: compaction groups
logstor: cache files for read
logstor: recovery: initial
logstor: add segment generation
logstor: reserve segments for compaction
logstor: index: buckets
logstor: add buffer header
logstor: add group_id
logstor: record generation
logstor: generation utility
logstor: use RIPEMD-160 for index key
test: add test_logstor.py
api: add logstor compaction trigger endpoint
replica: add logstor to db
schema: add logstor cf property
logstor: initial commit
db: disable tablet balancing with logstor
db: add logstor experimental feature flag
Trie-based sstable indexes are supposed to be (hopefully) a better default than the old BIG indexes.
Make the new format a new default for new clusters by naming ms in the default scylla.yaml.
New functionality. No backport needed.
This PR is basically Michał's one https://github.com/scylladb/scylladb/pull/26377, Jakub's https://github.com/scylladb/scylladb/pull/27332 fixing `sstables_manager::get_highest_supported_format()` and one test fix.
Closesscylladb/scylladb#28960
* github.com:scylladb/scylladb:
db/config: announce ms format as highest supported
db/config: enable `ms` sstable format by default
cluster/dtest/bypass_cache_test: switch from highest_supported_sstable_format to chosen_sstable_format
api/system: add /system/chosen_sstable_version
test/cluster/dtest: reduce num_tokens to 16
Add a segment_set member to replica::compaction_group that manages the
logstor segments that belong to the compaction group, similarly to how
it manages sstables. Add also a separator buffer in each compaction
group.
When writing a mutation to a compaction group, the mutation is written
to the active segment and to the separator buffer of the compaction
group, and when the separator buffer is flushed the segment is added to
the compaction_group's segment set.
add barrier operation that forces switch of the active segment and
separator, and waits for all existing segments to close and all
separators to flush.
Fixes: SCYLLADB-244
Disables snapshot control such that any active ops finish/fail
before proceeding with decommission.
Note: snapshot control provided as argument, not member ref
due to storage_service being used from both main and cql_test_env.
(The latter has no snapshot_ctl to provide).
Could do the snapshot lockout on API level, but want to do
pre-checks before this.
Note: this just disables backup/snapshot fully. Could re-enable
after decommission, but this seems somewhat pointless.
v2:
* Add log message to snapshot shutdown
* Make test use log waiting instead of timeouts
Closesscylladb/scylladb#28980
Replace CAS contention histograms in storage proxy stats with
estimated_histogram_with_max<128> and switch metrics/API aggregation to the
new histogram path.
Introduce a dedicated cas_contention_histogram alias and use it for
cas_read_contention and cas_write_contention.
Update API histogram reduction to merge the new histogram type via
estimated_histogram_with_max_merge.
Convert API JSON serialization to explicit offsets/counts using
get_buckets_offsets() and get_buckets_counts().
Export CAS contention metrics with to_metrics_histogram(...) instead of the
legacy get_histogram(1, 8) path for consistent bucket handling.
Returns the sstable version currently chosen for use in for new sstables.
We are adding it because some tests want to know what format they are
writing (tests using upgradesstable, tests which check stats that only
apply to one of the index types, etc).
(Currently they are using `highest_supported_sstable_format` for this
purpose, which is inappropriate, and will become invalid if a non-latest
format is the default).
The PR removes most of the code that assumes that group0 and raft topology is not enabled. It also makes sure that joining a cluster in no raft mode or upgrading a node in a cluster that not yet uses raft topology to this version will fail.
Refs #15422
No backport needed since this removes functionality.
Closesscylladb/scylladb#28514
* https://github.com/scylladb/scylladb:
group0: fix indentation after previous patch
raft_group0: simplify get_group0_upgrade_state function since no upgrade can happen any more
raft_group0: move service::group0_upgrade_state to use fmt::formatter instead of iostream
raft_group0: remove unused code from raft_group0
node_ops: remove topology over node ops code
topology: fix indentation after the previous patch
topology: drop topology_change_enabled parameter from raft_group0 code
storage_service: remove unused handle_state_* functions
gossiper: drop wait_for_gossip_to_settle and deprecate correspondent option
storage_service: fix indentation after the last patch
storage_service: remove gossiper bootstrapping code
storage_service: drop get_group_server_if_raft_topolgy_enabled
storage_service: drop is_topology_coordinator_enabled and its uses
storage_service: drop run_with_api_lock_in_gossiper_mode_only
topology: remove code that assumes raft_topology_change_enabled() may return false
test: schema_change_test: make test_schema_digest_does_not_change_with_disabled_features tests run in raft mode
test: schema_change_test: drop schema tests relevant for no raft mode only
topology: remove upgrade to raft topology code
group0: remove upgrade to group0 code
group0: refuse to boot if a cluster is still is not in a raft topology mode
storage_service: refuse to join a cluster in legacy mode
There is a handful of places in the code related to dictionary
compression which calls get_units to acquire semaphore units but the
returned future is not awaited, seemingly by mistake. The result of
get_units is assigned to a variable - which is reasonable at a glance
because the semaphore units need to be assigned to a variable in order
to control their scope - but at the same time if co_await is mistakenly
omitted, like here, doing so will silence the nodiscard check of
seastar::future and, effectively, the get_units call will be nearly
useless. Unfortunately, this is an easy mistake to make.
Fix the places in the code that acquire semaphore units via get_units
but never await the future returned by it. I found them by manual code
inspection, so I hope that I didn't miss any.
Closesscylladb/scylladb#28581
This patchset replaces permissions cache based on loading_cache with a new unified (permissions and roles), full, coherent auth cache.
Reason for the change is that we want to improve scenarios under stress and simplify operation manuals. New cache doesn't require any tweaking. And it behaves particularly better in scenarios with lots of schema entities (e.g. tables) combined with unprepared queries. Old cache can generate few thousands of extra internal tps due to cache refresh.
Benchmark of unprepared statements (just to populate the cache) with 1000 tables shows 3k tps of internal reads reduction and 9.1% reduction of median instructions per op. So many tables were used to show resource impact, cache could be filled with other resource types to show the same improvement.
Backport: no, it's a new feature.
Fixes https://github.com/scylladb/scylladb/issues/7397
Fixes https://github.com/scylladb/scylladb/issues/3693
Fixes https://github.com/scylladb/scylladb/issues/2589
Fixes https://scylladb.atlassian.net/browse/SCYLLADB-147Closesscylladb/scylladb#28078
* github.com:scylladb/scylladb:
test: boost: add auth cache tests
auth: add cache size metrics
docs: conf: update permissions cache documentation
auth: remove old permissions cache
auth: use unified cache for permissions
auth: ldap: add permissions reload to unified cache
auth: add permissions cache to auth/cache
auth: add service::revoke_all as main entry point
auth: explicitly life-extend resource in auth_migration_listener
There are some places that get `map<foo, bar>` and return it to the caller as `"key": string(foo), "value": string(bar)` json. For that there's `map_to_key_value()` helper in api.hh that re-formats the map into a vector of json elements and returns it, letting seastar json-ize that vector.
Recently in seastar there appeared stream_range_as_array() helper that helps streaming any range without converting it into intermediate collection. Some of the hottest users of `map_to_key_value()` had been converted, this PR converts few remainders and removes the helper in question to encourage further usage of the stream_range_as_array().
Code cleanup, not backporting
Closesscylladb/scylladb#28491
* github.com:scylladb/scylladb:
api: Remove map_to_key_value() helpers
api: Streamify view_build_statuses handler
api: Streamify few more storage_service/ handlers
api: Add map_to_json() helper
api: Coroutinize view_build_statuses handler
Similarly to previous patch, the handler can stream the map of build
statuses. Unlike previous patch, it doesn't need to fmt::format() key
and value, as these are strings already.
It could be a map_to_json<string, string> partial specialization, but
there's so far only one caller, so probably not worth it yet.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Like get_token_endpoint one streams the map that it got from storage
service, the get_ownership and get_effective_ownership can do the same.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The get_token_endpoint handler converts iterator of std::map into
generated maplist_mapper type. Next patch will do the same for more
handlers, so it's good to have a helper converter for it.
As a nice side effect, it's possible to avoid multiline lambda argument
to stream_range_as_array().
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
This reverts commit c8cff94a5a.
Re-enabling incremental repair on master with "Aborting on shard 0 during
scaleout + repair #26041" and "Failure to attach sstables in streaming consumer
leaves sealed sstables on disk #27414" fixed.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Closesscylladb/scylladb#28120
