Currently the function calls boost::partial_sort with a middle
iterator that might be out of bound and cause undefined behavior.
Check the vector size, and do a partial sort only if its longer
than `max_sstables`, otherwise sort the whole vector.
Fixesscylladb/scylladb#20608
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Closesscylladb/scylladb#20609
(cherry picked from commit 39ce358d82)
Refs: scylladb/scylladb#20609
The cleanup compaction task is a maintenance operation that runs after
topology changes. So, run it under the maintenance scheduling group to
avoid interference with regular compaction tasks. Also remove the share
allocations done by the cleanup task, as they are unnecessary when
running under the maintenance group.
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
Closesscylladb/scylladb#20582
When purging regular tombstone consult the min_live_timestamp,
if available.
For shadowable_tombstones, consult the
min_memtable_live_row_marker_timestamp,
if available, otherwise fallback to the min_live_timestamp.
If both are missing, fallback to the legacy
(and inaccurate) min_timestamp.
Fixesscylladb/scylladb#20423Fixesscylladb/scylladb#20424
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Before we add a new, is_shadowable, parameter to it.
And define global `can_always_purge` and `can_never_purge`
functions, a-la `always_gc` and `never_gc`.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
And define `never_gc` globally, same as `always_gc`
Before adding a new, is_shadowable parameter to it.
Since it is used in the context of compaction
it better fits compaction_garbage_collector header
rather than tombstone.hh
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
To return the minimum live timestamp and live row-marker
timestamp across a compaction_group, storage_group, or
table_state.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
When split, scrub, and upgrade compactions ran under the compaction
group, they had to bump up their shares to a minimum of 200 to prevent
slow progress as they neared completion, especially in workloads with
inconsistent ingestion rates. Since commit e86965c2 moved these
compactions to the maintenance group, this share bump is no longer
necessary. This patch removes the unnecessary share allocation.
Fixes#20224
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
Closesscylladb/scylladb#20495
Any expired tombstone can be garbage collected if it doesn't shadow data in the commit log, memtable, or uncompacting SSTables.
This PR introduces a new mode to major compaction, enabled by the `consider_only_existing_data` flag that bypasses these checks. When enabled, memtables and old commitlog segments are cleared with a system-wide flush and all the sstables (after flush) are included in the compaction, so that it works with all data generated up to a given time point.
This new mode works with the assumption that newly written data will not be shadowed by expired tombstones. So it ignores new sstables (and new data written to memtable) created after compaction started. Since there was a system wide flush, commitlog checks can also be skipped when garbage collecting tombstones. Introducing data shadowed by a tombstone during compaction can lead to undefined behavior, even without this PR, as the tombstone may or may not have already been garbage collected.
Fixes#19728Closesscylladb/scylladb#20031
* github.com:scylladb/scylladb:
cql-pytest: add test to verify consider_only_existing_data compaction option
tools/scylla-nodetool: add consider-only-existing-data option to compact command
api: compaction: add `consider_only_existing_data` option
compaction: consider gc_check_only_compacting_sstables when deducing max purgeable timestamp
compaction: do not check commitlog if gc_check_only_compacting_sstables is enabled
tombstone_gc_state: introduce with_commitlog_check_disabled()
compaction: introduce new option to check only compacting sstables for gc
compaction: rename maybe_flush_all_tables to maybe_flush_commitlog
compaction: maybe_flush_all_tables: add new force_flush param
Added a new parameter `consider_only_existing_data` to major compaction
API endpoints. When enabled, major compaction will:
- Force-flush all tables.
- Force a new active segment in the commit log.
- Compact all existing SSTables and garbage-collect tombstones by only
checking the SSTables being compacted. Memtables, commit logs, and
other SSTables not part of the compaction will not be checked, as they
will only contain newer data that arrived after the compaction
started.
The `consider_only_existing_data` is passed down to the compaction
descriptor's `gc_check_only_compacting_sstables` option to ensure that
only the existing data is considered for garbage collection.
The option is also passed to the `maybe_flush_commitlog` method to make
sure all the tables are flushed and a new active segment is created in
the commit log.
Fixes#19728
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
When gc_check_only_compacting_sstables is enabled,
get_max_purgeable_timestamp should not check memtables and other
sstables that are not part of the compaction to deduce the max purgeable
timestamp.
Refs #19728
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
When the compaction_descriptor's gc_check_only_compacting_sstables flag
is enabled, create and pass a copy of the get_tombstone_gc_state that
will skip checking the commitlog.
Refs #19728
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
Added new option, `gc_check_only_compacting_sstables`, to
compaction_descriptor to control the garbage collection behavior. The
subsequent patches will use this flag to decide if the garbage
collection has to check only the SSTables being compacted to collect
tombstones. This option is disabled for now and will be enabled based on
a new compaction parameter that will be added later in this patch
series.
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
Major compaction flushes all tables as a part of flushing the commitlog.
After forcing new active segments in the commitlog, all the tables are
flushed to enable reclaim of older commitlog segments. The main goal is
to flush the commitlog and flushing all the table is just a dependency.
Rename maybe_flush_all_tables to maybe_flush_commitlog so that it
reflects the actual intent of the major compaction code. Added a new
wrapper method to database::flush_all_tables(),
database::flush_commitlog(), that is now called from
maybe_flush_commitlog.
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
Add a new parameter, `force_flush` to the maybe_flush_all_tables()
method. Setting `force_flush` to true will flush all the tables
regardless of when they were flushed last. This will be used by the new
compaction option in a following patch.
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
instead of chaining the conditions with '&&', break them down.
for two reasons:
* for better readability: to group the conditions with the same
purpose together
* so we don't look up the table twice. it's an anti-pattern of
using STL, and it could be confusing at first glance.
this change is a cleanup, so it does not change the behavior.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#20369
To prevent stalls due to large number of tokens.
For example, large cluster with say 70 nodes can have
more than 16K tokens.
Fixes#19757Closesscylladb/scylladb#19758
* github.com:scylladb/scylladb:
abstract_replication_strategy: make get_ranges async
database: get_keyspace_local_ranges: get vnode_effective_replication_map_ptr param
compaction: task_manager_module: open code maybe_get_keyspace_local_ranges
alternator: ttl: token_ranges_owned_by_this_shard: let caller make the ranges_holder
alternator: ttl: can pass const gms::gossiper& to ranges_holder
alternator: ttl: ranges_holder_primary: unconstify _token_ranges member
alternator: ttl: refactor token_ranges_owned_by_this_shard
Currently "table removal" is logged as a reason of compaction stop for table drop,
tablet cleanup and tablet split. Modify log to reflect the reason.
Closesscylladb/scylladb#20042
* github.com:scylladb/scylladb:
test: add test to check compaction stop log
compaction: fix compaction group stop reason
To prevent stalls due to large number of tokens.
For example, large cluster with say 70 nodes can have
more than 16K tokens.
Fixes#19757
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Prepare for making the function async.
Then, it will need to hold on to the erm while getting
the token_ranges asynchronously.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
It is used only here and can be simplified by
checking if the keyspace replication strategy
is per table by the caller.
Prepare for making get_keyspace_local_ranges async.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Currently the major compaction task impl grabs this (non-updateable)
value from db::config. That's not good, all services including
compaction manager have their own configs from which they take options.
Said that, this patch puts the said option onto
compaction_manager::config, makes use of it and configures one from
db::config on start (and tests).
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closesscylladb/scylladb#20174
compaction_manager::remove passes "table removal" as a reason
of stopping ongoing compactions, but currently remove method
is also called when a tablet is migrated or split.
Pass the actual reason of compaction stop, so that logs aren't
misleading.
In order to fix the race between split and repair, we must introduce
the ability to split an "offline" sstable, one that wasn't added
to any of the table's sstable set yet.
It's not safe to split a sstable after adding it to the set, because
a failure to split can result in unsplit data left in the set, causing
split to fail down the road, since the coordinator thinks this replica
has only split data in the set.
Refs #19378.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
If parent_info argument of compaction_manager::perform_compaction
is std::nullopt, then created compaction executor isn't tracked by task
manager. Currently, all compaction operations should by visible in task
manager.
Modify split methods to keep split executor in task manager. Get rid of
the option to bypass task manager.
Closesscylladb/scylladb#19995
* github.com:scylladb/scylladb:
compaction: replace optional<task_info> with task_info param
compaction: keep split executor in task manager
assert() is traditionally disabled in release builds, but not in
scylladb. This hasn't caused problems so far, but the latest abseil
release includes a commit [1] that causes a 1000 insn/op regression when
NDEBUG is not defined.
Clearly, we must move towards a build system where NDEBUG is defined in
release builds. But we can't just define it blindly without vetting
all the assert() calls, as some were written with the expectation that
they are enabled in release mode.
To solve the conundrum, change all assert() calls to a new SCYLLA_ASSERT()
macro in utils/assert.hh. This macro is always defined and is not conditional
on NDEBUG, so we can later (after vetting Seastar) enable NDEBUG in release
mode.
[1] 66ef711d68Closesscylladb/scylladb#20006
compaction_manager::perform_compaction does not create task manager
task for compaction if parent_info is set to std::nullopt. Currently,
we always want to create task manager task for compaction.
Remove optional from task info parameters which start compaction.
Track all compactions with task manager.
rwlock was added to protect iterations against concurrent updates to the map.
the updates can happen when allocating a new tablet replica or removing an old one (tablet cleanup).
the rwlock is very problematic because it can result in topology changes blocked, as updating
token metadata takes the exclusive lock, which is serialized with table wide ops like
split / major / explicit flush (and those can take a long time).
to get rid of the lock, we can copy the storage group map and guard individual groups with a gate
(not a problem since map is expected to have a maximum of ~100 elements).
so cleanup can close that gate (carefully closed after stopping individual groups such that
migrations aren't blocked by long-running ops like major), and ongoing iterations (e.g. triggered
by nodetool flush) can skip a group that was closed, as such a group is being migrated out.
Check documentation added to compaction_group.hh to understand how
concurrent iterations and updates to the map work without the rwlock.
Yielding variants that iterate over groups are no longer returning group
id since id stability can no longer be guaranteed without serializing split
finalization and iteration.
Fixes#18821.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
C++23 made std::unique_ptr constexpr. A side effect of this (presumably)
is that the compiler compiles it more eagerly, requiring the full definition
of the class in std::make_unique, while it previously was content with
finding the definition later.
One victim of this change is compaction_manager::strategy_control; define
it earlier to build with C++23.
flat_mutation_reader_v2 was introduced in a pair of commits in 2021:
e3309322c3 "Clone flat_mutation_reader related classes into v2 variants"
08b5773c12 "Adapt flat_mutation_reader_v2 to the new version of the API"
as a replacement for flat_mutation_reader, using range_tombstone_change
instead of range_tombstone to represent represent range tombstones. See
those commits for more information.
The transition was incremental; the last use of the original
flat_mutation_reader was removed in 2022 in commit
026f8cc1e7 "db: Use mutation_partition_v2 in mvcc"
In turn, flat_mutation_reader was introduced in 2017 in commit
748205ca75 "Introduce flat_mutation_reader"
To transition from a mutation_reader that nested rows within
a partition in a separate stream, to a flat reader that streamed
partitions and rows in the same stream.
Here, we reclaim the original name and rename the awkward
flat_mutation_reader_v2 to mutation_reader.
Note that mutation_fragment_v2 remains since we still use the original
for compatibilty, sometimes.
Some notes about the transition:
- files were also renamed. In one case (flat_mutation_reader_test.cc), the
rename target already existed, so we rename to
mutation_reader_another_test.cc.
- a namespace 'mutation_reader' with two definitions existed (in
mutation_reader_fwd.hh). Its contents was folded into the mutation_reader
class. As a result, a few #includes had to be adjusted.
Closesscylladb/scylladb#19356
Normally, the space overhead for TWCS is 1/N, where is number of windows. But during off-strategy, the overhead is 100% because input sstables cannot be released earlier.
Reshaping a TWCS table that takes ~50% of available space can result in system running out of space.
That's fixed by restricting every TWCS off-strategy job to 10% of free space in disk. Tables that aren't big will not be penalized with increased write amplification, as all input (disjoint) sstables can still be compacted in a single round.
Fixes#16514.
Closesscylladb/scylladb#18137
* github.com:scylladb/scylladb:
compaction: Reduce twcs off-strategy space overhead to 10% of free space
compaction: wire storage free space into reshape procedure
sstables: Allow to get free space from underlying storage
replica: don't expose compaction_group to reshape task
Currently if task_manager::task::impl::abort preempts before children
are recursively aborted and then the task gets unregistered, we hit
use after free since abort uses children vector which is no
longer alive.
Modify abort method so that it goes over all tasks in task manager
and aborts those with the given parent.
Fixes: #19304.
TWCS off-strategy suffers with 100% space overhead, so a big TWCS table
can cause scylla to run out of disk space during node ops.
To not penalize TWCS tables, that take a small percentage of disk,
with increased write ampl, TWCS off-strategy will be restricted to
10% of free disk space. Then small tables can still compact all
disjoint sstables in a single round.
Fixes#16514.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
compaction_group sits in replica layer and compaction layer is
supposed to talk to it through compaction::table_state only.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Pass compaction group id to
shard_reshaping_compaction_task_impl::reshape_compaction_group.
Modify table::as_table_state to return table_state of the given
compaction group.
When a compaction strategy uses garbage collected sstables to track
expired tombstones, do not use complete partition estimates for them,
instead, use a fraction of it based on the droppable tombstone ratio
estimate.
Fixes#18283
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
Closesscylladb/scylladb#18465
std::optional formatting changed while moving from the home-grown formatter to
the fmt provided formatter; don't rely on it for user visible messages.
Here, the optional formatted is known to be engaged, so just print it.
Closesscylladb/scylladb#18533
base timestamps are feeded into the sstable writer for calculating
delta, used by varints. given that expired ssts are bypassed, we
don't have to account them. so if we compacting fully expired and
new sstable together, we can save a bit by having a base ts closer
to the data actually written into output. also I wanted to move
the calculation into the loop in setup(), to avoid two iterations
over input set that can have even more than 1k elements.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Closesscylladb/scylladb#18504
before this change, we rely on the default-generated fmt::formatter created from operator<<, but fmt v10 dropped the default-generated formatter.
in this change, we include `fmt/ranges.h` and/or `fmt/std.h` for formatting the container types, like vector, map optional and variant using {fmt} instead of the homebrew formatter based on operator<<.
with this change, the changes adding fmt::formatter and the changes using ostream formatter explicitly, we are allowed to drop `FMT_DEPRECATED_OSTREAM` macro.
Refs scylladb#13245
Closesscylladb/scylladb#17968
* github.com:scylladb/scylladb:
treewide: do not define FMT_DEPRECATED_OSTREAM
treewide: include fmt/ranges.h and/or fmt/std.h
utils/managed_bytes: add support for fmt::to_string() to bytes and friends
