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 define formatters for `parition_entry::printer`,
and drop its operator<< .
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#17812
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 define formatters for
* mutation_partition_v2::printer
* frozen_mutation::printer
* mutation
their operator<<:s are dropped.
Refs #13245Closesscylladb/scylladb#17769
* github.com:scylladb/scylladb:
mutation: add fmt::formatter for mutation
mutation: add fmt::formatter for frozen_mutation::printer
mutation: add fmt::formatter for mutation_partition_v2::printer
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 define formatters for mutation. but its operator<<
is preserved, as we are still using our homebrew generic formatter
for printing `std::vector<mutation>`, and this formatter is using
operator<< for printing the elements in vector.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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 define formatters for frozen_mutation::printer,
and drop its operator.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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 define formatters for mutation_partition_v2::printer, and
drop its operator<<
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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 define formatters for `clustering_interval_set`
their operator<<:s are dropped
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#17593
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 define formatters for `position_range`, and the
helpers for printing related types are dropped.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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 define formatters for
* mutation_fragment
* range_tombstone_stream
their operator<<:s are dropped
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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 define formatters for mutation_fragment_v2::printer
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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 define formatters for
* canonical_mutation
* atomic_cell_view
* atomic_cell
* atomic_cell_or_collection::printer
Refs #13245Closesscylladb/scylladb#17506
* github.com:scylladb/scylladb:
mutation: add fmt::formatter for canonical_mutation
mutation: add fmt::formatter for atomic_cell_view and atomic_cell
mutation: add fmt::formatter for atomic_cell_or_collection::printer
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 define formatters for canonical_mutation
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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 define formatters for
* atomic_cell_view
* atomic_cell
and drop their operator<<:s.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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 define formatters for
`atomic_cell_or_collection::printer`, and drop its operator<<.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Unfortunately, fmt v10 dropped support for operator<< formatters,
forcing us to replace the huge number of operator<< implementations
in our code by uglier and templated fmt::formatter implementations
to get Scylla to compile on modern distros (such as Fedora 39) :-(
Kefu has already started doing this migration, here is my small
contribution - the formatter for mutation_fragment_v2::kind.
This patch is need to compile, for example,
build/dev/mutation/mutation_fragment_stream_validator.o.
I can't remove the old operator<< because it's still used by
the implementation of other operator<< functions. We can remove
all of them when we're done with this coversion. In the meantime,
I replaced the original implementation of operator<< by a trivial
implementation just passing the work to the new fmt::print support.
Refs #13245
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closesscylladb/scylladb#17432
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 define formatters for
* clustering_row::printer
* static_row::printer
* partition_start
* partition_end
* mutation_fragment::printer
and drop their operator<<:s
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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 define formatters for
* row_tombstone
* row_marker
* deletable_row::printer
* row::printer
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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 define formatters for `mutation_partition::printer`,
and drop its operator<<.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#17419
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 define formatters for
`collection_mutation_view::printer`, and drop its
operator<<.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#17300
Adds a test reproducing https://github.com/scylladb/scylladb/issues/16759, and the instrumentation needed for it.
Closesscylladb/scylladb#17208
* github.com:scylladb/scylladb:
row_cache_test: test cache consistency during memtable-to-cache merge
row_cache: use preemption_source in update()
utils: preempt: add preemption_source
codespell reports that "statics" could be the misspelling of
"statistics". but "static" here means the static column(s). so
replace "static" with more specific wording.
Refs #589
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#17216
To facilitate testing the state of cache after the update is preempted
at various points, pass a preemption_source& to update() instead of
calling the reactor directly.
In release builds, the calls to preemption_source methods should compile
to the same direct reactor calls as today. Only in dev mode they should
add an extra branch. (However, the `preemption_source&` argument has
to be shoveled in any mode).
Anonymous namespace implies internal linkage for its members.
When it is defined in a header, then each translation unit,
which includes such header defines its own unique instance
of members of the unnamed namespace that are ODR-used within
that translation unit.
This can lead to unexpected results including code bloat
or undefined behavior due to ODR violations.
This change aligns the code with the following guidelines:
- CppCoreGuidelines: "SF.21: Don’t use an unnamed (anonymous)
namespace in a header"
- SEI CERT C++: "DCL59-CPP. Do not define an unnamed namespace
in a header file"
Signed-off-by: Patryk Wrobel <patryk.wrobel@scylladb.com>
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 define a formatter for `atomic_cell_view::printer`
and `atomic_cell::printer` respectively, and remove their operator<<().
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#16602
Fixes some typos as found by codespell run on the code.
In this commit, I was hoping to fix only comments, not user-visible alerts, output, etc.
Follow-up commits will take care of them.
Refs: https://github.com/scylladb/scylladb/issues/16255
Signed-off-by: Yaniv Kaul <yaniv.kaul@scylladb.com>
reconcilable_result_builder passes range tombstone changes to _rt_assembler
using table schema, not query schema.
This means that a tombstone with bounds (a; b), where a < b in query schema
but a > b in table schema, will not be emitted from mutation_query.
This is a very serious bug, because it means that such tombstones in reverse
queries are not reconciled with data from other replicas.
If *any* queried replica has a row, but not the range tombstone which deleted
the row, the reconciled result will contain the deleted row.
In particular, range deletes performed while a replica is down will not
later be visible to reverse queries which select this replica, regardless of the
consistency level.
As far as I can see, this doesn't result in any persistent data loss.
Only in that some data might appear resurrected to reverse queries,
until the relevant range tombstone is fully repaired.
This series fixes the bug and adds a minimal reproducer test.
Fixes#10598Closesscylladb/scylladb#16003
* github.com:scylladb/scylladb:
mutation_query_test: test that range tombstones are sent in reverse queries
mutation_query: properly send range tombstones in reverse queries
A schema upgrade appends a MVCC version B after an existing version A.
The last dummy in B is added to the front of LRU,
so it will be evicted after the entries in A.
This alone doesn't quite violate the "older versions are evicted first" rule,
because the new last dummy carries no information. But apply_monotonically
generally assumes that entries on the same position have the obvious
eviction order, even if they carry no information. Thus, after the merge,
the rule can become broken.
The proposed fix is as follows:
- In the case where A is merged into B, the merged last dummy
inherits the link of A.
- The merging of B into anything is prevented until its merge with A is finished.
This is relatively hacky, because it still involves a state that
goes against some natural expectations granted by the "older versions..."
rule. A less hacky fix would be to ensure that the new dummy is inserted
into a proper place in the eviction order to begin with.
Or, better yet, we could eliminate the rule altogether.
Aside from being very hard to maintain, it also prevents the introduction
of any eviction algorithm other than LRU.
to have feature parity with `configure.py`. we won't need this
once we migrate to C++20 modules. but before that day comes, we
need to stick with C++ headers.
we generate a rule for each .hh files to create a corresponding
.cc and then compile it, in order to verify the self-containness of
that header. so the number of rule is quite large, to avoid the
unnecessary overhead. the check-header target is enabled only if
`Scylla_CHECK_HEADERS` option is enabled.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#15913
reconcilable_result_builder passes range tombstone changes to _rt_assembler
using table schema, not query schema.
This means that a tombstone with bounds (a; b), where a < b in query schema
but a > b in table schema, are not be emitted from mutation_query.
This is a very serious bug, because it means that such tombstones in reverse
queries are not reconciled with data from other replicas.
If *any* queried replica has a row, but not the range tombstone which deleted
the row, the reconciled result will contain the deleted row.
In particular, range deletes performed while a replica is down, will not
later be visible to reverse queries which select this replica, regardless of the
consistency level.
As far as I can see, this doesn't result in any persistent data loss.
Only in that some data might appear resurrected to reverse queries,
until the relevant range tombstone is fully repaired.
The copy assignment operator of _ck can throw
after _type and _bound_weight have already been changed.
This leaves position_in_partition in an inconsistent state,
potentially leading to various weird symptoms.
The problem was witnessed by test_exception_safety_of_reads.
Specifically: in cache_flat_mutation_reader::add_to_buffer,
which requires the assignment to _lower_bound to be exception-safe.
The easy fix is to perform the only potentially-throwing step first.
Fixes#15822Closesscylladb/scylladb#15864
the `utils::UUID` class is not used by the implementation of
`canonical_mutation`, so let's remove the include from this source file.
the `#include` was originally added in
5a353486c6, but that commit did
add any code using UUID to this file.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#15731
The partition key size was ignored by the accounter, as well as the
partition tombstone. As a result, a sequence of partitions with just
tombstones would be accounted as taking no memory and page size
limitter to not kick in.
Fix by accounting the real size of accumulated frozen_mutation.
Also, break pages across partitions even if there are no live rows.
The coordinator can handle it now.
Refs #7933
Currently, mutation query on replica side will not respond with a result
which doesn't have at least one live row. This causes problems if there
is a lot of dead rows or partitions before we reach a live row, which
stems from the fact that resulting reconcilable_result will be large:
* Large allocations. Serialization of reconcilable_result causes large
allocations for storing result rows in std::deque
* Reactor stalls. Serialization of reconcilable_result on the replica
side and on the coordinator side causes reactor stalls. This impacts
not only the query at hand. For 1M dead rows, freezing takes 130ms,
unfreezing takes 500ms. Coordinator does multiple freezes and
unfreezes. The reactor stall on the coordinator side is >5s.
* Large repair mutations. If reconciliation works on large pages, repair
may fail due to too large mutation size. 1M dead rows is already too
much: Refs #9111.
This patch fixes all of the above by making mutation reads respect the
memory accounter's limit for the page size, even for dead rows.
This patch also addresses the problem of client-side timeouts during
paging. Reconciling queries processing long strings of tombstones will
now properly page tombstones,like regular queries do.
My testing shows that this solution even increases efficiency. I tested
with a cluster of 2 nodes, and a table of RF=2. The data layout was as
follows (1 partition):
Node1: 1 live row, 1M dead rows
Node2: 1M dead rows, 1 live row
This was designed to trigger reconciliation right from the very start of
the query.
Before:
Running query (node2, CL=ONE, cold cache)
Query done, duration: 140.0633503ms, pages: 101, result: [Row(pk=0, ck=3000000, v=0)]
Running query (node2, CL=ONE, hot cache)
Query done, duration: 66.7195275ms, pages: 101, result: [Row(pk=0, ck=3000000, v=0)]
Running query (all-nodes, CL=ALL, reconcile, cold-cache)
Query done, duration: 873.5400742ms, pages: 2, result: [Row(pk=0, ck=0, v=0), Row(pk=0, ck=3000000, v=0)]
After:
Running query (node2, CL=ONE, cold cache)
Query done, duration: 136.9035122ms, pages: 101, result: [Row(pk=0, ck=3000000, v=0)]
Running query (node2, CL=ONE, hot cache)
Query done, duration: 69.5286021ms, pages: 101, result: [Row(pk=0, ck=3000000, v=0)]
Running query (all-nodes, CL=ALL, reconcile, cold-cache)
Query done, duration: 162.6239498ms, pages: 100, result: [Row(pk=0, ck=0, v=0), Row(pk=0, ck=3000000, v=0)]
Non-reconciling queries have almost identical duration (1 few ms changes
can be observed between runs). Note how in the after case, the
reconciling read also produces 100 pages, vs. just 2 pages in the before
case, leading to a much lower duration (less than 1/4 of the before).
Refs #7929
Refs #3672
Refs #7933Fixes#9111
This reverts commit 628e6ffd33, reversing
changes made to 45ec76cfbf.
The test included with this PR is flaky and often breaks CI.
Revert while a fix is found.
Fixes: #15371
The partition key size was ignored by the accounter, as well as the
partition tombstone. As a result, a sequence of partitions with just
tombstones would be accounted as taking no memory and page size
limitter to not kick in.
Fix by accounting the real size of accumulated frozen_mutation.
Also, break pages across partitions even if there are no live rows.
The coordinator can handle it now.
Refs #7933
Currently, mutation query on replica side will not respond with a result
which doesn't have at least one live row. This causes problems if there
is a lot of dead rows or partitions before we reach a live row, which
stems from the fact that resulting reconcilable_result will be large:
* Large allocations. Serialization of reconcilable_result causes large
allocations for storing result rows in std::deque
* Reactor stalls. Serialization of reconcilable_result on the replica
side and on the coordinator side causes reactor stalls. This impacts
not only the query at hand. For 1M dead rows, freezing takes 130ms,
unfreezing takes 500ms. Coordinator does multiple freezes and
unfreezes. The reactor stall on the coordinator side is >5s.
* Large repair mutations. If reconciliation works on large pages, repair
may fail due to too large mutation size. 1M dead rows is already too
much: Refs #9111.
This patch fixes all of the above by making mutation reads respect the
memory accounter's limit for the page size, even for dead rows.
This patch also addresses the problem of client-side timeouts during
paging. Reconciling queries processing long strings of tombstones will
now properly page tombstones,like regular queries do.
My testing shows that this solution even increases efficiency. I tested
with a cluster of 2 nodes, and a table of RF=2. The data layout was as
follows (1 partition):
Node1: 1 live row, 1M dead rows
Node2: 1M dead rows, 1 live row
This was designed to trigger reconciliation right from the very start of
the query.
Before:
Running query (node2, CL=ONE, cold cache)
Query done, duration: 140.0633503ms, pages: 101, result: [Row(pk=0, ck=3000000, v=0)]
Running query (node2, CL=ONE, hot cache)
Query done, duration: 66.7195275ms, pages: 101, result: [Row(pk=0, ck=3000000, v=0)]
Running query (all-nodes, CL=ALL, reconcile, cold-cache)
Query done, duration: 873.5400742ms, pages: 2, result: [Row(pk=0, ck=0, v=0), Row(pk=0, ck=3000000, v=0)]
After:
Running query (node2, CL=ONE, cold cache)
Query done, duration: 136.9035122ms, pages: 101, result: [Row(pk=0, ck=3000000, v=0)]
Running query (node2, CL=ONE, hot cache)
Query done, duration: 69.5286021ms, pages: 101, result: [Row(pk=0, ck=3000000, v=0)]
Running query (all-nodes, CL=ALL, reconcile, cold-cache)
Query done, duration: 162.6239498ms, pages: 100, result: [Row(pk=0, ck=0, v=0), Row(pk=0, ck=3000000, v=0)]
Non-reconciling queries have almost identical duration (1 few ms changes
can be observed between runs). Note how in the after case, the
reconciling read also produces 100 pages, vs. just 2 pages in the before
case, leading to a much lower duration (less than 1/4 of the before).
Refs #7929
Refs #3672
Refs #7933Fixes#9111
Currently, streaming and repair processes and sends data as-is. This is wasteful: streaming might be sending data which is expired or covered by tombstones, taking up valuable bandwidth and processing time. Repair additionally could be exposed to artificial differences, due to different nodes being in different states of compactness.
This PR adds opt-in compaction to `make_streaming_reader()`, then opts in all users. The main difference being in how these choose the current compaction time to use:
* Load'n'stream and streaming uses the current time on the local node.
* Repair uses a centrally chosen compaction time, generated on the repair master and propagated to al repair followers. This is to ensure all repair participants work with the exact state of compactness.
Importantly, this compaction does *not* purge tombstones (tombstone GC is disabled completely).
Fixes: https://github.com/scylladb/scylladb/issues/3561Closes#14756
* github.com:scylladb/scylladb:
replica: make_[multishard_]streaming_reader(): make compaction_time mandatory
repair/row_level: opt in to compacting the stream
streaming: opt-in to compacting the stream
sstables_loader: opt-in for compacting the stream
replica/table: add optional compacting to make_multishard_streaming_reader()
replica/table: add optional compacting to make_streaming_reader()
db/config: add config item for enabling compaction for streaming and repair
repair: log the error which caused the repair to fail
readers: compacting_reader: use compact_mutation_state::abandon_current_partition()
mutation/mutation_compactor: allow user to abandon current partition
Currently, the compactor requires a valid stream and thus abandoning a
partition in the middle was not possible. This causes some complications
for the compacting reader, which implements methods such as
`next_partition()` which is possibly called in the middle of a
partition. In this case the compacting reader attempts to close the
partition properly by inserting a synthetic partition-end fragment into
the stream. This is not enough however as it doesn't close any range
tombstone changes that might be active. Instead of piling on more
complexity, add an API to the compactor which allows abandoning the
current partition.
The mutation compactor has a validator which it uses to validate the stream of mutation fragments that passes through it. This validator is supposed to validate the stream as it enters the compactor, as opposed to its compacted form (output). This was true for most fragment kinds except range tombstones, as purged range tombstones were not visible to
the validator for the most part.
This mistake was introduced by https://github.com/scylladb/scylladb/commite2c9cdb576, which itself was a flawed attempt at fixing an error seen because purged tombstones were not terminated by the compactor.
This patch corrects this mistake by fixing the above problem properly: on page-cut, if the validator has an active tombstone, a closing tombstone is generated for it, to avoid the false-positive error. With this, range tombstones can be validated again as they come in.
The existing unit test checking the validation in the compactor is greatly expanded to check all (I hope) different validation scenarios.
Closes#13817
* github.com:scylladb/scylladb:
test/mutation_test: test_compactor_validator_sanity_test
mutation/mutation_compactor: fix indentation
mutation/mutation_compactor: validate the input stream
mutation: mutation_fragment_stream_validating_filter: add accessor to underlying validator
readers: reader-from-fragment: don't modify stream when created without range
The mutation compactor has a validator which it uses to validate the
stream of mutation fragments that passes through it. This validator is
supposed to validate the stream as it enters the compactor, as opposed
to its compacted form (output). This was true for most fragment kinds
except range tombstones, as purged range tombstones were not visible to
the validator for the most part.
This mistake was introduced by e2c9cdb576, which itself was a flawed
attempt at fixing an error seen because purged tombstones were not
terminated by the compactor.
This patch corrects this mistake by fixing the above problem properly:
on page-cut, if the validator has an active tombstone, a closing
tombstone is generated for it, to avoid the false-positive error. With
this, range tombstones can be validated again as they come in.
