Insteadof std::runtime_error with a message that
resembles no_such_column_family, throw a
no_such_column_family given the keyspace and table uuid.
The latter can be explicitly caught and handled if needed.
Refs #8612
Test: unit(dev)
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Message-Id: <20210608113605.91292-1-bhalevy@scylladb.com>
Eliminate not used includes and replace some more includes
with forward declarations where appropriate.
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Now that it returns a future that always waits on
pending flushes there is no point in calling it `request_flush`.
`flush()` is simpler and better describes its function.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
It is currently possible that _memtables->add_memtable()
will throw after _memtables->clear(), leaving the memtables
list completely empty. However, we do rely on always
having at least one allocated in the memtables list
as active_memtable() references a lw_shared_ptr<memtable>
at the back of the memtables vector, and it expected
to always be allocated via add_memtable() upon construction
and after clear().
This change moves the implementation of this convention
to memtable_list::clear() and makes the latter exception safe
by first allocating the to-be-added empty memtable and
only then clearing the vector.
Refs #8749
Test: unit(dev)
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Message-Id: <20210530100232.2104051-1-bhalevy@scylladb.com>
We have enabled off-strategy compaction for bootstrap, replace,
decommission and removenode operations when repair based node operation
is enabled. Unlike node operations like replace or decommission, it is
harder to know when the repair of a table is finished because users can
send multiple repair requests one after another, each request repairing
a few token ranges.
This patch wires off-strategy compaction for regular repair by adding
a timeout based automatic off-strategy compaction trigger mechanism.
If there is no repair activity for sometime, off-strategy compaction
will be triggered for that table automatically.
Fixes#8677Closes#8678
In https://github.com/scylladb/scylla/issues/8609,
table::stop() that is called from database::drop_column_family
is expected to wait on outstanding flushes by calling
_memtable->request_flush(), but the memtable_list is considered
empty() at this point as it has a single empty memtable,
so request_flush() returns a ready future, without waiting
on outstanding flushes. This change replaces the call to
request_flush with flush().
Fix that by either returning _flush_coalescing future
that resolves when the memtable is sealed, if available,
or go through the get_flush_permit and
_dirty_memory_manager->flush_one song and dance, even though
the memtable is empty(), as the latter waits on pending flushes.
Fixes#8609
Test: unit(dev)
DTest: alternator_tests.py:AlternatorTest.test_batch_with_auto_snapshot_false(debug)
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Message-Id: <20210524143438.1056014-1-bhalevy@scylladb.com>
As a function returning a future, simplify
its interface by handling any exceptions and
returning an exceptional future instead of
propagating the exception.
In this specific case, throwing from advance_and_await()
will propagate through table::await_pending_* calls
short-circuiting a .finally clause in table::stop().
Also, mark as noexcept methods of class table calling
advance_and_await and table::await_pending_ops that depends on them.
Fixes#8636
A followup patch will convert advance_and_await to a coroutine.
This is done separately to facilitate backporting of this patch.
Test: unit(dev)
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Message-Id: <20210511161407.218402-1-bhalevy@scylladb.com>
Similar to the already existing get_reader_concurrency_semaphore(),
this method determines the appropriate max result size for the query
class, which is deduced from the current scheduling group. This method
shares its scheduling group -> query class association mechanism with
the above mentioned semaphore getter.
"
From now on, offstrategy compaction is triggered on completion of repair-based
removenode. So compaction will no longer act aggressively while removenode
is going on, which helps reducing both latency and operation time.
Refs #5226.
"
* 'offstrategy_removenode' of github.com:raphaelsc/scylla:
repair: Wire offstrategy compaction to repair-based removenode
table: introduce trigger_offstrategy_compaction()
repair/row_level: make operations_supported static const
Currently said method uses the system semaphore as a catch-all for all
scheduling groups it doesn't know about. This is incompatible with the
recent forward-porting of the service-level infrastructure as it means
that all service level related scheduling groups will fall back to the
system scheduling group, which causes two problems:
* They will experience much limited concurrency, as the system semaphore
is assigned much less count units, to match the much more limited
internal traffic.
* They compete with internal reads, severely impacting the respective
internal processes, potentially causing extreme slowdown, or even
deadlock in the case of an internal query executed on behalf of a
user query being blocked on the latter.
Even if we don't have any custom service level scheduling groups at the
moment, it is better to change this such that unknown scheduling groups
fall-back to using the user semaphore. We don't expect any new internal
scheduling group to pop up any time soon (and if they do we can adjust
get_reader_concurrency_semaphore() accordingly), but we do expect user
scheduling groups to be created in the future, even dynamically.
To minimize the chance of the wrong workload being associated with the
user semaphore, all statically created scheduling groups are now
explicitly listed in `get_reader_concurrency_semaphore()`, to make their
association with the respective semaphore explicit and documented.
Added a unit test which also checks the correct association for all
these scheduling groups.
Fixes: #8508
Tests: unit(dev)
Signed-off-by: Botond Dénes <bdenes@scylladb.com>
Message-Id: <20210420105156.94002-1-bdenes@scylladb.com>
The database.hh is the central recursive-headers knot -- it has ~50
includes. This patch leaves only 34 (it remains the champion though).
Similar thing for database.cc.
Both changes help the latter compile ~4% faster :)
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20210414183107.30374-1-xemul@scylladb.com>
this function will be used on repair-based operation completion,
to notify table about the need to start offstrategy compaction
process on the maintenance sstables produced by the operation.
Function which notifies about bootstrap and replace completion
is changed to use this new function.
Removenode and decommission will reuse this function.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Instead of `mutation_query()` from `mutation_query.hh`. The latter is
about to be retired as we want to migrate all users to
`table::mutation_query()`.
As part of this change, move away from `mutation_query_stage` too. This
brings the code paths of the two query variants closer together, as they
both have an execution stage declared in `database`.
We want to migrate `database::mutation_query()` off `mutation_query()`
to use `table::mutation_query()` instead. The reason is the same as for
making `table::query()` standalone: the `mutation_query()`
implementation increasingly became specific to how tables are queried
and is about to became even more specific due to impending changes to
how permits are obtained. As no-one in the codebase is doing generic
mutation queries on generic mutation sources we can just make this a
member of table.
This patch just adds `table::mutation_query()`, no user exists yet.
`table::mutation_query()` is identical to `mutation_query()`, except
that it is a coroutine.
Off-strategy compaction is about incrementally reshaping the off-strategy
sstables in maintenance set, using our existing reshape mechanism, until
the set is ready for integration into the main sstable set.
The whole operation is done in maintenance mode, using the streaming
scheduling group.
We can do it this way because data in maintenance set is disjoint, so
effects on read amplification is avoided by using
partitioned_sstable_set, which is able to efficiently and incrementally
retrieve data from disjoint sstables.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
SSTables that are off-strategy should be excluded by this function as
it's used to select candidates for regular compaction.
So in addition to only returning candidates from the main set, let's
also rename it to precisely reflect its behavior.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
This new sstable set will hold sstables created by repair-based
operations. A repair-based op creates 1 sstable per vrange (256),
so sstables added to this new set are disjoint, therefore they
can be efficiently read from using partitioned_sstable_set.
Compound set is changed to include this new set, so sstables in
this new set are automatically included when creating readers,
computing statistics, and so on.
This new set is not backlog tracked, so changes were needed to
prevent a sstable in this set from being added or removed from
the tracker.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
From now own, _sstables becomes the compound set, and _main_sstables refer
only to the main sstables of the table. In the near future, maintenance
set will be introduced and will also be managed by the compound set.
So add_sstable() and on_compaction_completion() are changed to
explicitly insert and remove sstables from the main set.
By storing compound set in _sstables, functions which used _sstables for
creating reader, computing statistics, etc, will not have to be changed
when we introduce the maintenance set, so code change is a lot minimized
by this approach.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
The purpose is to allow the code to be eventually reused by maintenance
sstable set, which will be soon introduced.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Evicts objects from caches which reflect sstable content, like the row
cache. In the future, it will also drop the page cache
and sstable index caches.
Unlike lsa/compact, doesn't cause reactor stalls.
The old lsa/compact call invokes memory reclamation, which is
non-preemptible. It also compacts LSA segments, so does more
work. Some use cases don't need to compact LSA segments, just want the
row cache to be wiped.
Message-Id: <20210301120211.36195-1-tgrabiec@scylladb.com>
The code that creates system keyspace open code a lot of things from
database::create_keyspace(). The patch makes create_keyspace() suitable
for both system and non system keyspaces and uses it to create system
keyspaces as well.
Message-Id: <20210209160506.1711177-1-gleb@scylladb.com>
Refs #6148
Commitlog disk limit was previously a "soft" limit, in that we allowed allocating new segments, even if we were over
disk usage max. This would also cause us sometimes to create new segments and delete old ones, if badly timed in
needing and releasing segments, in turn causing useless disk IO for pre-allocation/zeroing.
This patch set does:
* Make limit a hard limit. If we have disk usage > max, we wait for delete or recycle.
* Make flush threshold configurable. Default is ask for flush when over 50% usage. (We do not wait for results)
* Make flush "partial". We flush X% of the used space (used - thres/2), and make the rp limit accordingly. This means we will try to clear the N oldest segments, not all. I.e. "lighter" flush. Of course, if the CL is wholly dominated by a single CF, this will not really help much. But when > 1 cf is used, it means we can skip those not having unflushed data < req rp.
* Force more eager flush/recycle if we're out of segments
Note: flush threshold is not exposed in scylla config (yet). Because I am unsure of wording, and even if it should.
Note: testing is sparse, esp. in regard to latency/timeouts added in high usage scenarios. While I can fairly easily provoke "stalls" (i.e. forced waiting for segments to free up) with simple C-S, it is hard to say exactly where in a more sane config (I set my limits looow) latencies will start accumulating.
Closes#7879
* github.com:scylladb/scylla:
commitlog: Force earlier cycle/flush iff segment reserve is empty
commitlog: Make segment allocation wait iff disk usage > max
commitlog: Do partial (memtable) flushing based on threshold
commitlog: Make flush threshold configurable
table: Add a flush RP mark to table, and shortcut if not above
The db::update_keyspace() needs sharded<storage_proxy>
reference, but the only caller of it already has it and
can pass one as argument.
tests: unit(dev)
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20210205175611.13464-3-xemul@scylladb.com>
The database lass have to duplicated functions keyspaces() and
get_keyspaces(). Drop the former since it is used in one place only.
Message-Id: <20210201135333.GA1403508@scylladb.com>
storage_service: Introduce load_and_stream
=== Introduction ===
This feature extends the nodetool refresh to allow loading arbitrary sstables
that do not belong to a node into the cluster. It loads the sstables from disk
and calculates the owning nodes of the data and streams to the owners
automatically.
From example, say the old cluster has 6 nodes and the new cluster has 3 nodes.
We can copy the sstables from the old cluster to any of the new nodes and
trigger the load and stream process.
This can make restores and migrations much easier.
=== Performance ===
I managed to get 40MB/s per shard on my build machine.
CPU: AMD Ryzen 7 1800X Eight-Core Processor
DISK: Samsung SSD 970 PRO 512GB
Assume 1TB sstables per node, each shard can do 40MB/s, each node has 32
shards, we can finish the load and stream 1TB of data in 13 mins on each
node.
1TB / 40 MB per shard * 32 shard / 60 s = 13 mins
=== Tests ===
backup_restore_tests.py:TestBackupRestore.load_and_stream_to_new_cluster_test
which creates a cluster with 4 nodes and inserts data, then use
load_and_stream to restore to a 2 nodes cluster.
=== Usage ===
curl -X POST "http://{ip}:10000/storage_service/sstables/{keyspace}?cf={table}&load_and_stream=true
=== Notes ===
Btw, with the old nodetool refresh, the node will not pick up the data
that does not belong to this node but it will not delete it either. One
has to run nodetool cleanup to remove those data manually which is a
surprise to me and probably to users as well. With load and stream, the
process will delete the sstables once it finishes stream, so no nodetool
cleanup is needed.
The name of this feature load and stream follows load and store in CPU world.
Fixes#7831Closes#7846
* github.com:scylladb/scylla:
storage_service: Introduce load_and_stream
distributed_loader: Add get_sstables_from_upload_dir
table: Add make_streaming_reader for given sstables set
"
Without interposer consumer on flush, it could happen that a new sstable,
produced by memtable flush, will not conform to the strategy invariant.
For example, with TWCS, this new sstable could span multiple time windows,
making it hard for the strategy to purge expired data. If interposer is
enabled, the data will be correctly segregated into different sstables,
each one spanning a single window.
Fixes#4617.
tests:
- mode(dev).
- manually tested it by forcing a flush of memtable spanning many windows
"
* 'segregation_on_flush_v2' of github.com:raphaelsc/scylla:
test: Add test for TWCS interposer on memtable flush
table: Wire interposer consumer for memtable flush
table: Add write_memtable_to_sstable variant which accepts flat_mutation_reader
table: Allow sstable write permit to be shared across monitors
memtable: Track min timestamp
table: Extend cache update to operate a memtable split into multiple sstables
Adds a second RP to table, marking where we flushed last.
If a new flush request comes in that is below this mark, we
can skip a second flush.
This is to (in future) support incremental CL flush.
This extension is needed for future work where a memtable will be segregated
during flush into one sstable or more. So now multiple sstables can be added
to the set after a memtable flush, and compaction is only triggered at the
end.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Functions for checking if the keyspace is system/internal were based
on sstring references, which is impractical compared to string views
and may lead to unnecessary creation of sstring instances.
On every compaction completion, sstable set is rebuilt from scratch.
With LCS and ~160G of data per shard, it means we'll have to create
a new sstable set with ~1000 entries whenever compaction completes,
which will likely result in reactor stalling for a significant
amount of time.
This is fixed by futurizing build_new_sstable_list(), so it will
yield whenever needed.
Fixes#7758.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
procedure is changed to return the new set, so caller will be responsible
for replacing the old set with the new one. this will allow our future
work where building new set and enabling it will be decoupled.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Fixes#7732
When truncating with auto_snapshot on, we try to verify the low rp mark
from the CF against the sstables discarded by the truncation timestamp.
However, in a scenario like:
Fill memtables
Flush
Truncate with snapshot A
Fill memtables some more
Truncate
Move snapshot A to upload + refresh (load old tables)
Truncate
The last op will assert, because while we have sstables loaded, which
will be discarded now, we did not in fact generate any _new_ ones
(since memtables are empty), and the RP we get back from discard is
one from an earlier generation set.
(Any permutation of events that create the situation "empty memtable" +
"non-empty sstables with only old tables" will generate the same error).
Added a check that before flushing checks if we actually have any
data, and if not, does not uphold the RP relation assert.
Closes#7799
Pending flushes can participate in races when a table
with auto_snapshot==false is dropped. The race is as follows:
1. A flush of table T is initiated
2. The flush operation is preempted
3. Table T is dropped without flushing, because it has auto_snapshot off
4. The flush operation from (2.) wakes up and continues
working on table T, which is already dropped
5. Segfault/memory corruption
To prevent such races, a phaser for pending flushes is introduced
This reverts commit dc77d128e9. It was reverted
due to a strange and unexplained diff, which is now explained. The
HEAD on the working directory being pulled from was set back, so git
thought it was merging the intended commits, plus all the work that was
committed from HEAD to master. So it is safe to restore it.
"
The storage service is called there to get the cached value
of db::system_keyspace::get_local_host_id(). Keeping the value
on database decouples it from storage service and kills one
more global storage service reference.
tests: unit(dev)
"
* 'br-remove-storage-service-from-counters-2' of https://github.com/xemul/scylla:
counters: Drop call to get_local_storage_service and related
counters: Use local id arg in transform_counter_update_to_shards
database: Have local id arg in transform_counter_updates_to_shards()
storage_service: Keep local host id to database
This reverts commit 0aa1f7c70a, reversing
changes made to 72c59e8000. The diff is
strange, including unrelated commits. There is no understanding of the
cause, so to be safe, revert and try again.
The local host id is now passed by argument, so we don't
need the counter_id::local() and some other methods that
call or are called by it.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
