For now this is almost a no-op because manager just calls
sstables_directory code back to create the lister.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Currently the utils/lister.cc code is in use to list regular files in a
directory. This patch wraps the lister into more abstract components
lister class.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Now the directory code has everyhting it needs to create sstable object
and can stop using the external lambda.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Yet another continuation to previous patch -- IO error handlers
generator is also needed to create sstables.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Continuation of one-before-previous patch. In order to create sstable
without external lambda the directory code needs schema.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
After previous patch sstables_directory code may no longer require for
semaphore argument, because it can get one from manager. This makes the
directory API shorter and simpler.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The sstables_directly accesses /var/lib/scylla/data in two ways -- lists
files in it and opens sstables. The latter is abdtracted with the help
of lambdas passed around, but the former (listing) is done by using
directory liters from utils.
Listing sstables components with directlry lister won't work for object
storage, the directory code will need to call some abstraction layer
instead. Opening sstables with the help of a lambda is a bit of
overkill, having sstables manager at hand could make it much simpler.
Said that, this patch makes sstables_directly reference sstables_manager
on start.
This change will also simplify directory semaphore usage (next patch).
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Currently this is a sharded<semaphore> started/stopped in main and
referenced by database in order to be fed into sstables code. This
semaphore always comes with the "concurrency" parameter that limits the
parallel_for_each parallelizm.
This patch wraps both together into directory_semaphore class. This
makes its usage simpler and will allow extending it in the future.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
There are several class sstable methods that reveal internal directory
path to caller. It's not object-storage-friendly. Fortunately, all the
callers of those methods had been patched not to work with full paths,
so these can be marked private.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
There's a table::move_sstables_from_staging() method that gets a bunch
of sstables and moves them from staging subdit into table's root
datadir. Not to flush the root dir for every sstable move, it asks the
sstable::move_to_new_dir() not to flush, but collects staging dir names
and flushes them and the root dir at the end altothether.
In order to make it more friendly to object-storage and to remove one
more caller of sstable::get_dir() the delayed_commit_changes struct is
introduced. It collects _all_ the affected dir names in unordered_set,
then allows flushing them. By default the move_to_new_dir() doesn't
receive this object and flushes the directories instantly.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The one effectively wraps existing seastar sync_directory() helper into
two io_check-s. It's simpler just to call the latter directly.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The method became unused since 70e5252a (table: no longer accept online
loading of SSTable files in the main directory) and the whole concept of
reshuffling sstables was dropped later by 7351db7c (Reshape upload files
and reshard+reshape at boot).
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closes#12165
std::hash isn't constexpr, so gcc refuses to make hash of generation_type
constexpr. It's pointless anyway since we never have a compile-time
sstable generation.
When started the sstable_directory is constructed with a bunch of booleans that control the way its process_sstable_dir method works. It's shorter and simpler to pass these booleans into method directly, all the more so there's another flag that's already passed like this.
Closes#12005
* github.com:scylladb/scylladb:
sstable_directory: Move all RAII booleans onto flags
sstable_directory: Convert sort-sstables argument to flags struct
sstable_directory: Drop default filter
There's a bunch of booleans that control the behavior of sstable
directory scanning. Currently they are described as verbose
bool_class<>-es and are put into sstable_directory construction time.
However, these are not used outside of .process_sstable_dir() method and
moving them onto recently added flags struct makes the code much
shorter (29 insertions(+), 121 deletions(-))
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The sstable_directory::process_sstable_dir() accepts a boolean to
control its behavior when collecting sstables. Turn this boolean into a
structure of flags. The intention is to extend this flags set in the
future (next patch).
This boolean is true all the time, but one place sets it to true in a
"verbose" manner, like this:
bool sort_sstables_according_to_owner = false;
process_sstable_dir(directory, sort_sstables_according_to_owner).get();
the local variable is not used anymore. Using designated initializers
solves the verbosity in a nicer manner.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
It's used as default argument for .reshape() method, but callers specify
it explicitly. At the same time the filter is simple enough and is only
used in one place so that the caller can just use explicit lambda.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The deletion log concept uses the fact that files are on a POSIX
filesystem. Support for another storage type will have to reimplement
this place, so keep the FS-specific code in _directory.cc file.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
It's no used by any other code, but to be used it requires the caller to
tranform TOC file names by prepending sstable directory to them. Things
get shorter and simpler if merging the helper code into the caller.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
It's called by a code that has fs::path at hand and internally uses
helpers that need fs::path too, so no need to convert it back and forth.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
It's a wrapper over output_stream with offset tracking and the tracking
is not needed to generate a log file. As a bonus of switching back we
get a stream.write(sstring) sugar.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Fragment reordering and fragment dropping bugs have been plaguing us since forever. To fight them we added a validator to the sstable write path to prevent really messed up sstables from being written.
This series adds validation to the mutation compactor. This will cover reads and compaction among others, hopefully ridding us of such bugs on the read path too.
This series fixes some benign looking issues found by unit tests after the validator was added -- although how benign a producer emitting two partition-ends depends entirely on how the consumer reacts to it, so no such bug is actually benign.
Fixes: https://github.com/scylladb/scylladb/issues/11174Closes#11532
* github.com:scylladb/scylladb:
mutation_compactor: add validator
mutation_fragment_stream_validator: add a 'none' validation level
test/boost/mutation_query_test: test_partition_limit: sort input data
querier: consume_page(): use partition_start as the sentinel value
treewide: use ::for_partition_end() instead of ::end_of_partition_tag_t{}
treewide: use ::for_partition_start() instead of ::partition_start_tag_t{}
position_in_partition: add for_partition_{start,end}()
The lister accepts sort of a filter -- what kind of entries to list, regular, directories or both. It currently uses unordered_set, but enum_set is shorter and better describes the intent.
Closes#12017
* github.com:scylladb/scylladb:
lister: Make lister::dir_entry_types an enum_set
database: Avoid useless local variable
This type is currently an unordered_set, but only consists of at most
two elements. Making it an enum_set renders it into a size_t variable
and better describes the intention.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Now that our toolchain is based on Fedora 37, we can rely on its
libdeflate rather than have to carry our own in a submodule.
Frozen toolchain is regenerated. As a side effect clang is updated
from 15.0.0 to 15.0.4.
Closes#12000
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
unlink_from_lru() allows for unlinking elements from cache without notifying
the cache. This messes up any potential cache bookkeeping.
Improved that by replacing all uses of unlink_from_lru() with calls to
lru::remove(), which does have access to cache's metadata.
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.
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
Since `_partition_size_entry` and `_rows_in_partition_entry`
are accessed at the same time when updated, and similarly
`_cell_size_entry` and `_elements_in_collection_entry`,
place the member pairs closely together to improve data
cache locality.
Follow the same order when preparing the
`scylla_metadata::large_data_stats` map.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
To save the map lookup on the hot write path,
keep each large data stats entry as a member in the writer
object and build a map for storing the disk_hash in the
scylla metadata only when finalizing it in consume_end_of_stream.
Fixes#11686
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
This fixes a regression introduced by 1e7a444, where table::get_sstable_set() isn't exposing all sstables, but rather only the ones in the main set. That causes user of the interface, such as get_sstables_by_partition_key() (used by API to return sstable name list which contains a particular key), to miss files in the maintenance set.
Fixes https://github.com/scylladb/scylladb/issues/11681.
Closes#11682
* github.com:scylladb/scylladb:
replica: Return all sstables in table::get_sstable_set()
sstables: Fix cloning of compound_sstable_set
The intention was that its clone() would actually clone the content
of an existing set into a new one, but the current impl is actually
moving the sets instead of copying them. So the original set
becomes invalid. Luckily, this problem isn't triggered as we're
not exposing the compound set in the table's interface, so the
compound_sstable_set::clone() method isn't being called.
Signed-off-by: Raphael S. Carvalho <raphaelsc@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>
And update the sstable elements_in_collection
stats entry.
Next step would be to forward it to
large_data_handler().maybe_record_large_cells().
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Add a new large_data_stats type and entry for keeping
the collection_elements_count_threshold and the maximum value
of collection_elements.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
The low-level `mutation_fragment_stream_validator` gets `reset()` methods that until now only the high-level `mutation_fragment_stream_validating_filter` had.
Active tombstone validation is pushed down to the low level validator.
The low level validator, which was a pain to use until now due to being very fussy on which subset of its API one used, is made much more robust, not requiring the user to stick to a subset of its API anymore.
Closes#11614
* github.com:scylladb/scylladb:
mutation_fragment_stream_validator: make interface more robust
mutation_fragment_stream_validator: add reset() to validating filter
mutation_fragment_stream_validator: move active tomsbtone validation into low level validator
Currently the active range tombstone change is validated in the high
level `mutation_fragment_stream_validating_stream`, meaning that users of
the low-level `mutation_fragment_stream_validator` don't benefit from
checking that tombstones are properly closed.
This patch moves the validation down to the low-level validator (which
is what the high-level one uses under the hood too), and requires all
users to pass information about changes to the active tombstone for each
fragment.
Long-term index caching in the global cache, as introduced in 4.6, is a major
pessimization for workloads where accesses to the index are (spacially) sparse.
We want to have a way to disable it for the affected workloads.
There is already infrastructure in place for disabling it for BYPASS CACHE
queries. One way of solving the issue is hijacking that infrastructure.
This patch adds a global flag (and a corresponding CLI option) which controls
index caching. Setting the flag to `false` causes all index reads to behave
like they would in BYPASS CACHE queries.
Consequences of this choice:
- The per-SSTable partition_index_cache is unused. Every index_reader has
its own, and they die together. Independent reads can no longer reuse the
work of other reads which hit the same index pages. This is not crucial,
since partition accesses have no (natural) spatial locality. Note that
the original reason for partition_index_cache -- the ability to share
reads for the lower and upper bound of the query -- is unaffected.
- The per-SSTable cached_file is unused. Every index_reader has its own
(uncached) input stream from the index file, and every
bsearch_clustered_cursor has its own cached_file, which dies together with
the cursor. Note that the cursor still can perform its binary search with
caching. However, it won't be able to reuse the file pages read by
index_reader. In particular, if the promoted index is small, and fits inside
the same file page as its index_entry, that page will be re-read.
It can also happen that index_reader will read the same index file page
multiple times. When the summary is so dense that multiple index pages fit in
one index file page, advancing the upper bound, which reads the next index
page, will read the same index file page. Since summary:disk ratio is 1:2000,
this is expected to happen for partitions with size greater than 2000
partition keys.
Fixes#11202
Adds support for splitting large partitions during compaction.
Large partitions introduce many problems, like memory overhead and
breaks incremental compaction promise. We want to split large
partitions across fixed-size fragments. We'll allow a partition
to exceed size limit by 10%, as we don't want to unnecessarily split
partitions that just crossed the limit boundary.
To avoid having to open a minimal of 2 fragments in a read, partition
tombstone will be replicated to every fragment storing the
partition.
The splitting isn't enabled by default, and can be used by
strategies that are run aware like ICS. LCS still cannot support
it as it's still using physical level metadata, not run id.
An incremental reader for sstable runs will follow soon.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
