The replace_entry() function is nothing more than a convenience for
calling delete_old_entry() and then create_entry(). But it is only used
once in the code, and we can just open-code the two calls instead of
the one.
The reason I want to change it now is that the shortcut replace_entry()
helped hide a bug (#11801) - replace_entry() works incorrectly if the
old and new row have the same key, because if they do we get a deletion
and creation of the same row with the same timestamp - and the deletion
wins. Having the two calls not hidden by a convenience function makes
this potential problem more apparent.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
"
There's an ongoing effort to move the endpoint -> {dc/rack} mappings
from snitch onto topology object and this set finalizes it. After it the
snitch service stops depending on gossiper and system keyspace and is
ready for de-globalization. As a nice side-effect the system keyspace no
longer needs to maintain the dc/rack info cache and its starting code gets
relaxed.
refs: #2737
refs: #2795
"
* 'br-snitch-dont-mess-with-topology-data-2' of https://github.com/xemul/scylla: (23 commits)
system_keyspace: Dont maintain dc/rack cache
system_keyspace: Indentation fix after previous patch
system_keyspace: Coroutinuze build_dc_rack_info()
topology: Move all post-configuration to topology::config
snitch: Start early
gossiper: Do not export system keyspace
snitch: Remove gossiper reference
snitch: Mark get_datacenter/_rack methods const
snitch: Drop some dead dependency knots
snitch, code: Make get_datacenter() report local dc only
snitch, code: Make get_rack() report local rack only
storage_service: Populate pending endpoint in on_alive()
code: Populate pending locations
topology: Put local dc/rack on topology early
topology: Add pending locations collection
topology: Make get_location() errors more verbose
token_metadata: Add config, spread everywhere
token_metadata: Hide token_metadata_impl copy constructor
gosspier: Remove messaging service getter
snitch: Get local address to gossip via config
...
This series is a step towards non-LRU cache algorithms.
Our cache items are able to unlink themselves from the LRU list. (In other words, they can be unlinked solely via a pointer to the item, without access to the containing list head). Some places in the code make use of that, e.g. by relying on auto-unlink of items in their destructor.
However, to implement algorithms smarter than LRU, we might want to update some cache-wide metadata on item removal. But any cache-wide structures are unreachable through an item pointer, since items only have access to themselves and their immediate neighbours. Therefore, we don't want items to unlink themselves — we want `cache.remove(item)`, rather than `item.remove_self()`, because the former can update the metadata in `cache`.
This series inserts explicit item unlink calls in places that were previously relying on destructors, gets rid of other self-unlinks, and adds an assert which ensures that every item is explicitly unlinked before destruction.
Closes#11716
* github.com:scylladb/scylladb:
utils: lru: assert that evictables are unlinked before destruction
utils: lru: remove unlink_from_lru()
cache: make all cache unlinks explicit
Our LSA cache is implemented as an auto_unlink Boost intrusive list, meaning
that elements of the list unlink themselves from the list automatically on
destruction. Some parts of the code rely on that, and don't unlink them
manually.
However, this precludes accurate bookkeeping about the cache. Elements only have
access to themselves and their neighbours, not to any bookkeeping context.
Therefore, a destructor cannot update the relevant metadata.
In this patch, we fix this by adding explicit unlink calls to places where it
would be done by a destructor. In a following patch, we will add an assert to
the destructor to check that every element is unlinked before destruction.
Today, we're completely blind about the progress of view updating
on Staging files. We don't know how long it will take, nor how much
progress we've made.
This patch adds visibility with a new metric that will inform
the number of bytes to be processed from Staging files.
Before any work is done, the metric tell us the total size to be
processed. As view updating progresses, the metric value is
expected to decrease, unless work is being produced faster than
we can consume them.
We're piggybacking on sstables::read_monitor, which allows the
progress metric to be updated whenever the SSTable reader makes
progress.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Closes#11751
In preparation for supporting IP address changes of Raft Group 0:
1) Always use start_server_for_group0() to start a server for group 0.
This will provide a single extension point when it's necessary to
prompt raft_address_map with gossip data.
2) Don't use raft::server_address in discovery, since going forward
discovery won't store raft::server_address. On the same token stop
using discovery::peer_set anywhere outside discovery (for persistence),
use a peer_list instead, which is easier to marshal.
Closes#11676
* github.com:scylladb/scylladb:
raft: (discovery) do not use raft::server_address to carry IP data
raft: (group0) API refactoring to avoid raft::server_address
raft: rename group0_upgrade.hh to group0_fwd.hh
raft: (group0) move the code around
raft: (discovery) persist a list of discovered peers, not a set
raft: (group0) always start group0 using start_server_for_group0()
Some good news finally. The saved dc/rack info about the ring is now
only loaded once on start. So the whole cache is not needed and the
loading code in storage_service can be greatly simplified
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The continuation of the previous patch -- all the code uses
topology::get_datacenter(endpoint) to get peers' dc string. The topology
still uses snitch for that, but it already contains the needed data.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
All the code out there now calls snitch::get_rack() to get rack for the
local node. For other nodes the topology::get_rack(endpoint) is used.
Since now the topology is properly populated with endpoints, it can
finally be patched to stop using snitch and get rack from its internal
collections
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
We plan to remove IP information from Raft addresses.
raft::server_address is used in Raft configuration and
also in discovery, which is a separate algorithm, as a handy data
structure, to avoid having new entities in RPC.
Since we plan to remove IP addresses from Raft configuration,
using raft::server_address in discovery and still storing
IPs in it would create ambiguity: in some uses raft::server_address
would store an IP, and in others - would not.
So switch to an own data structure for the purposes of discovery,
discovery_peer, which contains a pair ip, raft server id.
Note to reviewers: ideally we should switch to URIs
in discovery_peer right away. Otherwise we may have to
deal with incompatible changes in discovery when adding URI
support to Scylla.
The l._d._h.'s way to update system keyspace is not like in other code.
Instead of a dedicated helper on the system_keyspace's side it executes
the insertion query directly with the help of qctx.
Now when the l._d._h. has the weak system keyspace reference it can
execute queries on _it_ rather than on the qctx.
Just like in previous patch, it needs to keep the sys._k.s. weak
reference alive until the query's future resolves.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Compaction manager now has the weak reference on the system keyspace
object and can use it to update its stats. It only needs to take care
and keep the shared pointer until the respective future resolves.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
There's a virtual method on table_state to update the entry in system
keyspace. It's an overkill to facilitate tests that don't want this.
With new system_keyspace weak referencing it can be made simpled by
moving the updating call to the compaction_manager itself.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
There's a circular dependency between system_keyspace and database. The
former needs the latter because it needs to execula local requests via
query_processor. The latter needs the former via compaction manager and
large data handler, database depends on both and these too need to
insert their entries into system keyspace.
To cut this loop the compaction manager and large data handler both get
a weak reference on the system keysace. Once system keyspace starts is
activcates this reference via the database call. When system keyspace is
shutdown-ed on stop, it deactivates the reference.
Technically the weak reference is implemented by marking the system_k.s.
object as async_sharded_service, and the "reference" in question is the
shared_from_this() pointer. When compaction manager or large data
handler need to update a system keyspace's table, they both hold an
extra reference on the system keyspace until the entry is committed,
thus making sure that sys._k.s. doesn't stop from under their feet. At
the same time, unplugging the reference on shutdown makes sure that no
new entries update will appear and the system_k.s. will eventually be
released.
It's not a C++ classical reference, because system_keyspace starts after
and stops before database.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Many services out there have one (sometimes called .drain()) that's
called early on stop and that's responsible for prearing the service for
stop -- aborting pending/in-flight fibers and alike.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
This method just jumps into topology.has_endpoint(). The change is
for consistency with other users of it and as a preparation for
topology.has_endpoint() future enhancements
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Yet another user of global qctx object. Making the method(s) non-static requires pushing the system_keyspace all the way down to size_estimate_virtual_reader and a small update of the cql_test_env
Closes#11738
* github.com:scylladb/scylladb:
system_keyspace: Make get_{local|saved}_tokens non static
size_estimates_virtual_reader: Pass sys_ks argument to get_local_ranges()
cql_test_env: Keep sharded<system_keyspace> reference
size_estimate_virtual_reader: Keep system_keyspace reference
system_keyspace: Pass sys_ks argument to install_virtual_readers()
system_keyspace: Make make() non-static
distributed_loader: Pass sys_ks argument to init_system_keyspace()
system_keyspace: Remove dangling forward declaration
This series adds support for detecting collections that have too many items
and recording them in `system.large_cells`.
A configuration variable was added to db/config: `compaction_collection_items_count_warning_threshold` set by default to 10000.
Collections that have more items than this threshold will be warned about and will be recorded as a large cell in the `system.large_cells` table. Documentation has been updated respectively.
A new column was added to system.large_cells: `collection_items`.
Similar to the `rows` column in system.large_partition, `collection_items` holds the number of items in a collection when the large cell is a collection, or 0 if it isn't. Note that the collection may be recorded in system.large_cells either due to its size, like any other cell, and/or due to the number of items in it, if it cross the said threshold.
Note that #11449 called for a new system.large_collections table, but extending system.large_cells follows the logic of system.large_partitions is a smaller change overall, hence it was preferred.
Since the system keyspace schema is hard coded, the schema version of system.large_cells was bumped, and since the change is not backward compatible, we added a cluster feature - `LARGE_COLLECTION_DETECTION` - to enable using it.
The large_data_handler large cell detection record function will populate the new column only when the new cluster feature is enabled.
In addition, unit tests were added in sstable_3_x_test for testing large cells detection by cell size, and large_collection detection by the number of items.
Closes#11449Closes#11674
* github.com:scylladb/scylladb:
sstables: mx/writer: optimize large data stats members order
sstables: mx/writer: keep large data stats entry as members
db: large_data_handler: dynamically update config thresholds
utils/updateable_value: add transforming_value_updater
db/large_data_handler: cql_table_large_data_handler: record large_collections
db/large_data_handler: pass ref to feature_service to cql_table_large_data_handler
db/large_data_handler: cql_table_large_data_handler: move ctor out of line
docs: large-rows-large-cells-tables: fix typos
db/system_keyspace: add collection_elements column to system.large_cells
gms/feature_service: add large_collection_detection cluster feature
test: sstable_3_x_test: add test_sstable_too_many_collection_elements
test: lib: simple_schema: add support for optional collection column
test: lib: simple_schema: build schema in ctor body
test: lib: simple_schema: cql: define s1 as static only if built this way
db/large_data_handler: maybe_record_large_cells: consider collection_elements
db/large_data_handler: debug cql_table_large_data_handler::delete_large_data_entries
sstables: mx/writer: pass collection_elements to writer::maybe_record_large_cells
sstables: mx/writer: add large_data_type::elements_in_collection
db/large_data_handler: get the collection_elements_count_threshold
db/config: add compaction_collection_elements_count_warning_threshold
test: sstable_3_x_test: add test_sstable_write_large_cell
test: sstable_3_x_test: pass cell_threshold_bytes to large_data_handler
test: sstable_3_x_test: large_data_handler: prepare callback for testing large_cells
test: sstable_3_x_test: large_data tests: use BOOST_REQUIRE_[GL]T
test: sstable_3_x_test: test_sstable_log_too_many_rows: use tests::random
Now all callers have system_keyspace reference at hand. This removes one
more user of the global qctx object
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
This method static calls system_keyspace::get_local_tokens(). Having the
system_keyspace reference will make this method non-static
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The s._e._v._reader::fill_buffer() method needs system keyspace to get
node's local tokens. Now it's a static method, having system_keyspace
reference will make it non-static
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The size-estimate-virtual-reader will need it, now it's available as
"this" from system_keyspace::make() method
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
This helper needs system_keyspace reference and using "this" as this
looks natural. Also this de-static-ification makes it possible to put
some sense into the invoke_on_all() call from init_system_keyspace()
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
It doesn't match the real system_keyspace_make() definition and is in
fact not needed, as there's another "real" one in database.hh
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
make the various large data thresholds live-updateable
and construct the observers and updaters in
cql_table_large_data_handler to dynamically update
the base large_data_handler class threshold members.
Fixes#11685
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
The "virtual dirty" term is not very informative. "Virtual" means
"not real", but it doesn't say in which way it isn't real.
In this case, virtual dirty refers to real dirty memory, minus
the portion of memtables that has been written to disk (but not
yet sealed - in that case it would not be dirty in the first
place).
I chose to call "the portion of memtables that has been written
to disk" as "spooled memory". At least the unique term will cause
people to look it up and may be easier to remember. From that
we have "unspooled memory".
I plan to further change the accounting to account for spooled memory
rather than unspooled, as that is a more natural term, but that is left
for later.
The documentation, config item, and metrics are adjusted. The config
item is practically unused so it isn't worth keeping compatibility here.
When the large_collection_detection cluster feature is enabled,
select the internal_record_large_cells_and_collections method
to record the large collection cell, storing also the collection_elements
column.
We want to do that only when the cluster feature is enabled
to facilitate rollback in case rolling upgrade is aborted,
otherwise system.large_cells won't be backward compatible
and will have to be deleted manually.
Delete the sstable from system.large_cells if it contains
elements_in_collection above threshold.
Closes#11449
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
For recording collection_elements of large_collections when
the large_collection_detection feature is enabled.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
And bump the schema version offset since the new schema
should be distinguishable from the previous one.
Refs scylladb/scylladb#11660
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Detect large_collections when the number of collection_elements
is above the configured threshold.
Next step would be to record the number of collection_elements
in the system.large_cells table, when the respective
cluster feature is enabled.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
The view builder builds the views from a given base table in
view_builder::batch_size batches of rows. After processing this many
rows, it suspends so the view builder can switch to building views for
other base tables in the name of fairness. When resuming the build step
for a given base table, it reuses the reader used previously (also
serving the role of a snapshot, pinning sstables read from). The
compactor however is created anew. As the reader can be in the middle of
a partition, the view builder injects a partition start into the
compactor to prime it for continuing the partition. This however only
included the partition-key, crucially missing any active tombstones:
partition tombstone or -- since the v2 transition -- active range
tombstone. This can result in base rows covered by either of this to be
resurrected and the view builder to generate view updates for them.
This patch solves this by using the detach-state mechanism of the
compactor which was explicitly developed for situations like this (in
the range scan code) -- resuming a read with the readers kept but the
compactor recreated.
Also included are two test cases reproducing the problem, one with a
range tombstone, the other with a partition tombstone.
Fixes: #11668Closes#11671
The logic to reject explicit snapshot of views/indexes was improved in aa127a2dbb. However, we never implemented auto-snapshot of
view/indexes when taking a snapshot of the base table.
This is implemented in this patch.
The implementation is built on top of
ba42852b0e
so it would be hard to backport to 5.1 or earlier
releases.
Fixes#11612
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Closes#11616
* github.com:scylladb/scylladb:
database: automatically take snapshot of base table views
api: storage_service: reject snapshot of views in api layer
The logic to reject explicit snapshot of views/indexes
was improved in aa127a2dbb.
However, we never implemented auto-snapshot of
view/indexes when taking a snapshot of the base table.
This is implemented in this patch.
The implementation is built on top of
ba42852b0e
so it would be hard to backport to 5.1 or earlier
releases.
Fixes#11612
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Rather than pushing the check to
`snapshot_ctl::take_column_family_snapshot`, just check
that explcitly when taking a snapshot of a particular
table by name over the api.
Other paths that call snapshot_ctl::take_column_family_snapshot
are internal and use it to snap views already.
With that, we can get rid of the allow_view_snapshots flag
that was introduced in aab4cd850c.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
When warning about a large cell/collection in a static row,
print that fact in the log warning to make it clearer.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Currently (since f3089bf3d1),
when printing a warning to the log about large rows and/or cells
the clustering key string is concatenated to the partition key string,
rendering the warning confsing and much less useful.
This patch adds a '/' delimiter to separate the fields,
and also uses one to separate the clustering key from the column name
for large cells. In case of a static cell, the clustering key is null
hence the warning will look like: `pk//column`.
This patch does NOT change anything in the large_* system
table schema or contents. It changes only the log warning format
that need not be backward compatible.
Fixes#11620
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Add cassandra functional - show warn/err when tombstone_warn_threshold/tombstone_failure_threshold reached on select, by partitions. Propagate raw query_string from coordinator to replicas.
Closes#11356
* github.com:scylladb/scylladb:
add utf8:validate to operator<< partition_key with_schema.
Show warn message if `tombstone_warn_threshold` reached on querier.
Found by a fragment stream validator added to the mutation-compactor (https://github.com/scylladb/scylladb/pull/11532). As that PR moves very slowly, the fixes for the issues found are split out into a PR of their own.
The first two of these issues seems benign, but it is important to remember that how benign an invalid fragment stream is depends entirely on the consumer of said stream. The present consumer of said streams may swallow the invalid stream without problem now but any future change may cause it to enter into a corrupt state.
The last one is a non-benign problem (again because the consumer reacts badly already) causing problems when building query results for range scans.
Closes#11604
* github.com:scylladb/scylladb:
shard_reader: do_fill_buffer(): only update _end_of_stream after buffer is copied
readers/mutation_readers: compacting_reader: remember injected partition-end
db/view: view_builder::execute(): only inject partition-start if needed
When querier read page with tombstones more than `tombstone_warn_threshold` limit - warning message appeared in logs.
If `tombstone_warn_threshold:0` feature disabled.
Refs scylladb#11410
When resuming a build-step, the view builder injects the partition-start
fragment of the last processed partition, to bring the consumer
(compactor) into the correct state before it starts to consume the
remainder of the partition content. This results in an invalid fragment
stream when the partition was actually over or there is nothing left for
the build step. Make the inject conditional on when the reader contains
more data for the partition.
Fixes: #11607
