propagate_replacement is used by incremental compaction to notify
ongoing compaction about sstable list updates, such that the
ongoing job won't hold reference to exhausted sstables.
So it needs to switch to table_state, too.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
- Use `sstables::generation_type` in more places
- Enforce conceptual separation of `sstables::generation_type` and `int64_t`
- Fix `extremum_tracker` so that `sstables::generation_type` can be non-default-constructible
Fixes#10796.
Closes#10844
* github.com:scylladb/scylla:
sstables: make generation_type an actual separate type
sstables: use generation_type more soundly
extremum_tracker: do not require default-constructible value types
Make the compaction manager for testing using
this class.
Makes sure to enable the compaction manager
and to stop it before it's destroyed.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
`generation_type` is (supposed to be) conceptually different from
`int64_t` (even if physically they are the same), but at present
Scylla code still largely treats them interchangeably.
In addition to using `generation_type` in more places, we
provide (no-op) `generation_value()` and `generation_from_value()`
operations to make the smoke-and-mirrors more believable.
The churn is considerable, but all mechanical. To avoid even
more (way, way more) churn, unit test code is left untreated for
now, except where it uses the affected core APIs directly.
Signed-off-by: Michael Livshin <michael.livshin@scylladb.com>
propagate_replacement() is an internal function that shouldn't be in
the public interface. No one besides an unit test for incremental
compaction needs it. In the future, I want to revisit incremental
compaction unit test to stop using it and only rely on public
interfaces
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20220506171647.81063-1-raphaelsc@scylladb.com>
There's a public call on replica::table to get back the compaction
manager reference. It's not needed, actually. The users of the call are
distributed loader which already has database at hand, and a test that
creates itw own instance of compaction manager for its testing tables
and thus also has it available.
tests: unit(dev)
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20220406171351.3050-1-xemul@scylladb.com>
For compaction to be able to purge expired data, like tombstones, a
sstable set snapshot is set in the compaction descriptor.
That's a decision that belongs to task type. For example, all regular
compaction enable GC, whereas scrub for example doesn't for safety
reasons.
The problem is that the decision is being made by every instantiation
of compaction_descriptor in the strategies, which is both unnecessary
and also adds lots of boilerplate to the code, making it hard to
understand and work with.
As sstable set snapshot is an implementation detail, a new method
is being added to compaction_descriptor to make the intention
clearer, making the interface easier to understand.
can_purge_tombstones, used previously by rewrite task only, is being
reused for communicating GC intention into task::compact_sstables().
The boilerplate was a pain when adding a new strategy method for
the ongoing work on cleanup, described by issue #10097.
Another benefit is that we'll now only create a set snapshot when
compaction will really run. Before, it could happen that the snapshot
would be discarded if the compaction attempt had to be postponed,
which is a waste of cpu cycles.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
The series overhauls the compaction_manager::task design and implementation
by properly layering the functionality between the compaction_manager
that deals with generic task execution, and the per-task business logic that is defined
in a set of classes derived from the generic task class.
While at it, the series introduces `task::state` and a set of helper functions to manage it
to prevent leaks in the statistics, fixing #9974.
Two more stats counter were exposed: `completed_tasks` and a new `postponed_tasks`.
Test: sstable_compaction_test
Dtest: compaction_test.py compaction_additional_test.py
Fixes#9974Closes#10122
* github.com:scylladb/scylla:
compaction_manager: use coroutine::switch_to
compaction_manager::task: drop _compaction_running
compaction_manager: move per-type logic to derived task
compaction_manager: task: add state enum
compaction_manager: task: add maybe_retry
compaction_manager: reevaluate_postponed_compactions: mark as noexcept
compaction_manager: define derived task types
compaction_manager: register_metrics: expose postponed_compactions
compaction_manager: register_metrics: expose failed_compactions
compaction_manager: register_metrics: expose _stats.completed_tasks
compaction: add documentation for compaction_type to string conversions
compaction: expose to_string(compaction_type)
compaction_manager: task: standardize task description in log messages
compaction_manager: refactor can_proceed
compaction_manager: pass compaction_manager& to task ctor
compaction_manager: use shared_ptr<task> rather than lw_shared_ptr
compaction_manager: rewrite_sstables: acquire _maintenance_ops_sem once
compaction_manager: use compaction_state::lock only to synchronize major and regular compaction
Move the business logic into the task specific classes.
Separating initialization during task construction,
from the compaction_done task, moved into
a do_run() method, and in some cases moving
a lambda function that was called per table (as in
rewrite_sstables) into a private method of the
derived class.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Not precise, as bytes_on_disk accounts for all components, but good enough
for testing purposes.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Memtables are a replica-side entity, and so are moved to the
replica module and namespace.
Memtables are also used outside the replica, in two places:
- in some virtual tables; this is also in some way inside the replica,
(virtual readers are installed at the replica level, not the
cooordinator), so I don't consider it a layering violation
- in many sstable unit tests, as a convenient way to create sstables
with known input. This is a layering violation.
We could make memtables their own module, but I think this is wrong.
Memtables are deeply tied into replica memory management, and trying
to make them a low-level primitive (at a lower level than sstables) will
be difficult. Not least because memtables use sstables. Instead, we
should have a memtable-like thing that doesn't support merging and
doesn't have all other funky memtable stuff, and instead replace
the uses of memtables in sstable tests with some kind of
make_flat_mutation_reader_from_unsorted_mutations() that does
the sorting that is the reason for the use of memtables in tests (and
live with the layering violation meanwhile).
Test: unit (dev)
Closes#10120
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
Move replica-oriented classes to the replica namespace. The main
classes moved are ::database, ::keyspace, and ::table, but a few
ancillary classes are also moved. There are certainly classes that
should be moved but aren't (like distributed_loader) but we have
to start somewhere.
References are adjusted treewide. In many cases, it is obvious that
a call site should not access the replica (but the data_dictionary
instead), but that is left for separate work.
scylla-gdb.py is adjusted to look for both the new and old names.
In order to avoid race condition introduced in 9dce1e4 the
index_reader should be closed prior to it's destruction.
This only exposes 4.4 and earlier releases to this specific race.
However, it is always a good idea to first close the index reader
and only then destroy it since it is most likely to be assumed by
all developers that will change the reader index in the future.
Ref #9704 (because on 4.4 and earlier releases are vulnerable).
Signed-off-by: Eliran Sinvani <eliransin@scylladb.com>
Closes#9705
there's no need for wrapping compaction_data in shared_ptr, also
let's kill unused params in create_compaction_data to simplify
its creation.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
compaction_info must only contain info data to be exported to the
outside world, whereas compaction_data will contain data for
controlling compaction behavior and stats which change as
compaction progresses.
This separation makes the interface clearer, also allowing for
future improvements like removing direct references to table
in compaction.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Today, compactions are tracked by both _compactions and _tasks,
where _compactions refer to actual ongoing compaction tasks,
whereas _tasks refer to manager tasks which is responsible for
spawning new compactions, retry them on failure, etc.
As each task can only have one ongoing compaction at a time,
let's move compaction into task, such that manager won't have to
look at both when deciding to do something like stopping a task.
So stopping a task becomes simpler, and duplication is naturally
gone.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Today, compaction is calling compaction manager to register / deregister
the compaction_info created by it.
This is a layer violation because manager sits one layer above
compaction, so manager should be responsible for managing compaction
info.
From now on, compaction_info will be created and managed by
compaction_manager. compaction will only have a reference to info,
which it can use to update the world about compaction progress.
This will allow compaction_manager to be simplified as info can be
coupled with its respective task, allowing duplication to be removed
and layer violation to be fixed.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
this run id is used to track partial runs that are being written to.
let's move it from info into task, as this is not an external info,
but rather one that belongs to compaction_manager.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
compaction_info must only contain info data to be exported to the
outside world, whereas compaction_data will contain data for
controlling compaction behavior and stats which change as
compaction progresses.
This separation makes the interface clearer, also allowing for
future improvements like removing direct references to table
in compaction.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Today, compactions are tracked by both _compactions and _tasks,
where _compactions refer to actual ongoing compaction tasks,
whereas _tasks refer to manager tasks which is responsible for
spawning new compactions, retry them on failure, etc.
As each task can only have one ongoing compaction at a time,
let's move compaction into task, such that manager won't have to
look at both when deciding to do something like stopping a task.
So stopping a task becomes simpler, and duplication is naturally
gone.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Today, compaction is calling compaction manager to register / deregister
the compaction_info created by it.
This is a layer violation because manager sits one layer above
compaction, so manager should be responsible for managing compaction
info.
From now on, compaction_info will be created and managed by
compaction_manager. compaction will only have a reference to info,
which it can use to update the world about compaction progress.
This will allow compaction_manager to be simplified as info can be
coupled with its respective task, allowing duplication to be removed
and layer violation to be fixed.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
this run id is used to track partial runs that are being written to.
let's move it from info into task, as this is not an external info,
but rather one that belongs to compaction_manager.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
The former constructs a memtable from the vector of mutations and
then does exactlty the same steps as the latter one -- creates an
sstable corresponding to the memtable.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
There are already four of them. Those working with the mutation reader
can be folded into one with some default args.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Index cursor for reads which bypass cache will use a private temporary
instance of the partition index cache.
Promoted index scanner (ka/la format) will not go through the page cache.
index_entry will be an LSA-managed object. Those have to be accessed
with care, with the LSA region locked.
This patch hides most of direct index_entry accesses inside the
index_reader so that users are safe.
The purpose of the class in question is to start sharded storage
service to make its global instance alive. I don't know when exactly
it happened but no code that instantiates this wrapper really needs
the global storage service.
Ref: #2795
tests: unit(dev), perf_sstable(dev)
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20210526170454.15795-1-xemul@scylladb.com>
Add a string describing where the sstables originated
from (e.g. memtable, repair, streaming, compaction, etc.)
If configure_writer is called with a nullptr, the origin
will be equal to an empty string.
Introduce test_env_sstables_manager that provides an overload
of configure_writer with no parmeters that calls the base-class'
configure_writer with "test" origin. This was to reduce the
code churn in this patch and to keep the tests simple.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
read_toc can be marked as noexcept now that new_sstable_component_file is.
With that, other methods that call it can be marked noexcept too.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
compaction.hh is one of our heavy headers, but some users just want to
use information on it about how to describe a compaction, not how to
perform one.
For that reason this patch splits the compaction_descriptor into a new
header.
The compaction_descriptor has, as a member type, compaction_options.
That is moved too, and brings with it the compaction_type. Both of those
structures would make sense in a separate header anyway.
The compaction_descriptor also wants the creator_fn and replacer_fn
functions. We also take this opportunity to rename them into something
more descriptive
Signed-off-by: Glauber Costa <glauber@scylladb.com>
Seastar recently lost support for the experimental Concepts Technical
Specification (TS) and gained support for C++20 concepts. Re-enable
concepts in Scylla by updating our use of concepts to the C++20
standard.
This change:
- peels off uses of the GCC6_CONCEPT macro
- removes inclusions of <seastar/gcc6-concepts.hh>
- replaces function-style concepts (no longer supported) with
equation-style concepts
- semicolons added and removed as needed
- deprecated std::is_pod replaced by recommended replacement
- updates return type constraints to use concepts instead of
type names (either std::same_as or std::convertible_to, with
std::same_as chosen when possible)
No attempt is made to improve the concepts; this is a specification
update only.
Message-Id: <20200531110254.2555854-1-avi@scylladb.com>
We will soon require a valid permit for all reads, including low level
index reads. The sstable layer has several internal reads which can not
be associated with either the user or the system read semaphores or it
would be very hard to obtain the correct semaphore, for limited/no gain.
To be able to pass a valid permit still, we either expose a permit
parameter so upper layers can pass down one, or create a local semaphore
for these reads and use that to obtain a permit.
The following methods now require a permit to be passed to them:
* `sstables::sstabe::read_data()`: only used in tests.
The following methods use internal semaphores:
* `sstables::sstable::generate_summary()` used when loading an sstable.
* `sstables::sstable::has_partition_key()`: used by a REST API method.
A variant of make_keys() which creates keys for the requested shard. As
this version is more generic than the existing local_shards_only
variant, the former is reimplemented on top of the latter.
