Since the end bound is exclusive, the end position should be
before_key(), not after_key().
Affects only tests, as far as I know, only there we can get an end
bound which is a clustering row position.
Would cause failures once row cache is switched to v2 representation
because of violated assumptions about positions.
Introduced in 76ee3f029cCloses#11823
The generator was first setting the marker then applied tombstones.
The marker was set like this:
row.marker() = random_row_marker();
Later, when shadowable tombstones were applied, they were compacted
with the marker as expected.
However, the key for the row was chosen randomly in each iteration and
there are multiple keys set, so there was a possibility of a key clash
with an earlier row. This could override the marker without applying
any tombstones, which is conditional on random choice.
This could generate rows with markers uncompacted with shadowable tombstones.
This broken row_cache_test::test_concurrent_reads_and_eviction on
comparison between expected and read mutations. The latter was
compacted because it went through an extra merge path, which compacts
the row.
Fix by making sure there are no key clashes.
Closes#11663
Given 3 row mutations:
m1 = {
marker: {row_marker: dead timestamp=-9223372036854775803},
tombstone: {row_tombstone: {shadowable tombstone: timestamp=-9223372036854775807, deletion_time=0}, {tombstone: none}}
}
m2 = {
marker: {row_marker: timestamp=-9223372036854775805}
}
m3 = {
tombstone: {row_tombstone: {shadowable tombstone: timestamp=-9223372036854775806, deletion_time=2}, {tombstone: none}}
}
We get different shadowable tombstones depending on the order of merging:
(m1 + m2) + m3 = {
marker: {row_marker: dead timestamp=-9223372036854775803},
tombstone: {row_tombstone: {shadowable tombstone: timestamp=-9223372036854775806, deletion_time=2}, {tombstone: none}}
m1 + (m2 + m3) = {
marker: {row_marker: dead timestamp=-9223372036854775803},
tombstone: {row_tombstone: {shadowable tombstone: timestamp=-9223372036854775807, deletion_time=0}, {tombstone: none}}
}
The reason is that in the second case the shadowable tombstone in m3
is shadwed by the row marker in m2. In the first case, the marker in
m2 is cancelled by the dead marker in m1, so shadowable tombstone in
m3 is not cancelled (the marker in m1 does not cancel because it's
dead).
This wouldn't happen if the dead marker in m1 was accompanied by a
hard tombstone of the same timestamp, which would effectively make the
difference in shadowable tombstones irrelevant.
Found by row_cache_test.cc::test_concurrent_reads_and_eviction.
I'm not sure if this situation can be reached in practice (dead marker
in mv table but no row tombstone).
Work it around for tests by producing a row tombstone if there is a
dead marker.
Refs #11307
Rather than defining generate_random,
and use respectively in unit tests.
(It was inherited from raft::internal::tagged_id.)
This allows us to shorten counter_id's definition
to just using utils::tagged_uuid<struct counter_id_tag>.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
The test simulates a situation where 2 threads issue flushes to 2
tables. Both issue small flushes, but one has injected reactor stalls.
This can lead to a situation where lots of small sstables accumulate on
disk, and, if compaction never has a chance to keep up, resources can be
exhausted.
(cherry picked from commit b5684aa96d)
(cherry picked from commit 25407a7e41)
This reverts commit aa8f135f64, reversing
changes made to 9a88bc260c. The patch
causes hangs during flush.
Also reverts parts of 411231da75 that impacted the unit test.
Fixes#10897.
The projected limited replacement of downgraded v1 mutation reader
will not do its own buffering, so this test will be pointless.
Signed-off-by: Michael Livshin <michael.livshin@scylladb.com>
mutation_source are going to be created only from v2 readers and the
::make_reader() method family is scheduled for removal.
Signed-off-by: Michael Livshin <michael.livshin@scylladb.com>
Dealing with the handful of tests that check range tombstones in
interesting ways and need more than search-and-replace.
Signed-off-by: Michael Livshin <michael.livshin@scylladb.com>
We don't have any upgrade_to_v2() left in production code, so no need to
keep testing it. Removing it from this test paves the way for removing
it for good (not in this series).
This method used to be a static one in
boost/flat_mutation_reader_test.cc. Turns out it is useful for other
tests based on the mutation source test suite, so move it into the
header of the latter to make it accessible.
The flat_mutation_reader files were conflated and contained multiple
readers, which were not strictly necessary. Splitting optimizes both
iterative compilation times, as touching rarely used readers doesn't
recompile large chunks of codebase. Total compilation times are also
improved, as the size of flat_mutation_reader.hh and
flat_mutation_reader_v2.hh have been reduced and those files are
included by many file in the codebase.
With changes
real 29m14.051s
user 168m39.071s
sys 5m13.443s
Without changes
real 30m36.203s
user 175m43.354s
sys 5m26.376s
Closes#10194
Although we have a log in run_mutation_reader_tests(), it is useful to
know where it was called from, when trying to find the test scenario
that failed.
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
The gc_grace_seconds is a very fragile and broken design inherited from
Cassandra. Deleted data can be resurrected if cluster wide repair is not
performed within gc_grace_seconds. This design pushes the job of making
the database consistency to the user. In practice, it is very hard to
guarantee repair is performed within gc_grace_seconds all the time. For
example, repair workload has the lowest priority in the system which can
be slowed down by the higher priority workload, so that there is no
guarantee when a repair can finish. A gc_grace_seconds value that is
used to work might not work after data volume grows in a cluster. Users
might want to avoid running repair during a specific period where
latency is the top priority for their business.
To solve this problem, an automatic mechanism to protect data
resurrection is proposed and implemented. The main idea is to remove the
tombstone only after the range that covers the tombstone is repaired.
In this patch, a new table option tombstone_gc is added. The option is
used to configure tombstone gc mode. For example:
1) GC a tombstone after gc_grace_seconds
cqlsh> ALTER TABLE ks.cf WITH tombstone_gc = {'mode':'timeout'} ;
This is the default mode. If no tombstone_gc option is specified by the
user. The old gc_grace_seconds based gc will be used.
2) Never GC a tombstone
cqlsh> ALTER TABLE ks.cf WITH tombstone_gc = {'mode':'disabled'};
3) GC a tombstone immediately
cqlsh> ALTER TABLE ks.cf WITH tombstone_gc = {'mode':'immediate'};
4) GC a tombstone after repair
cqlsh> ALTER TABLE ks.cf WITH tombstone_gc = {'mode':'repair'};
In addition to the 'mode' option, another option 'propagation_delay_in_seconds'
is added. It defines the max time a write could possibly delay before it
eventually arrives at a node.
A new gossip feature TOMBSTONE_GC_OPTIONS is added. The new tombstone_gc
option can only be used after the whole cluster supports the new
feature. A mixed cluster works with no problem.
Tests: compaction_test.py, ninja test
Fixes#3560
[avi: resolve conflicts vs data_dictionary]
This change makes row cache support reverse reads natively so that reversing wrappers are not needed when reading from cache and thus the read can be executed efficiently, with similar cost as the forward-order read.
The database is serving reverse reads from cache by default after this. Before, it was bypassing cache by default after 703aed3277.
Refs: #1413
Tests:
- unit [dev]
- manual query with build/dev/scylla and cache tracing on
Closes#9454
* github.com:scylladb/scylla:
tests: row_cache: Extend test_concurrent_reads_and_eviction to run reverse queries
row_cache: partition_snapshot_row_cursor: Print more details about the current version vector
row_cache: Improve trace-level logging
config: Use cache for reversed reads by default
config: Adjust reversed_reads_auto_bypass_cache description
row_cache: Support reverse reads natively
mvcc: partition_snapshot: Support slicing range tombstones in reverse
test: flat_mutation_reader_assertions: Consume expected range tombstones before end_of_partition
row_cache: Log produced range tombstones
test: Make produces_range_tombstone() report ck_ranges
tests: lib: random_mutation_generator: Extract make_random_range_tombstone()
partition_snapshot_row_cursor: Support reverse iteration
utils: immutable-collection: Make movable
intrusive_btree: Make default-initialized iterator cast to false
Currently in the reverse run we wrap the test-provided mutation-source
and create a v1 reader with it, forcing a conversion if the
mutation-source has a v2 factory. Worse still, if the test is v2 native,
there will be a double conversion. This patch fixes this by creating a
wrapper mutation-source appropriate to the version of the underlying
factory of the wrapped mutation-source.
Most of the machinery was already implemented since it was used when
jumping between clustering ranges of a query slice. We need only perform
one additional thing when performing an index skip during
fast-forwarding: reset the stored range tombstone in the consumer (which
may only be stored in fast-forwarding mode, so it didn't matter that it
wasn't reset earlier). Comments were added to explain the details.
As a preparation for the change, we extend the sstable reversing reader
random schema test with a fast-forwarding test and include some minor
fixes.
Fixes#9427.
Closes#9484
* github.com:scylladb/scylla:
query-request: add comment about clustering ranges with non-full prefix key bounds
sstables: mx: enable position fast-forwarding in reverse mode
test: sstable_conforms_to_mutation_source_test: extend `test_sstable_reversing_reader_random_schema` with fast-forwarding
test: sstable_conforms_to_mutation_source_test: fix `vector::erase` call
test: mutation_source_test: extract `forwardable_reader_to_mutation` function
test: random_schema: fix clustering column printing in `random_schema::cql`
Query time must be fetched after populate. If compaction is executed
during populate it may be executed with timestamp later than query_time.
This would cause the test expected compaction and compaction during
populate to be executed at different time points producing different
results. The result would be sporadic test failures depending on relative
timing of those operations. If no other mutations happen after populate,
and query_time is later than the compaction time during population, we're
guaranteed to have the same results.
Message-Id: <20211123134808.105068-1-mikolaj.sieluzycki@scylladb.com>
flat_reader_assertions::produces_range_tombstone() does not actually
check range tombstones beyond the fact that they are in fact range
tombstones (unless non-empty ck_ranges is passed).
Fixing the immediate problem reveals that:
* The assertion logic is not flexible enough to deal with
creatively-split or creatively-overlapping range tombstones.
* Some existing tests involving range tombstones are in fact wrong:
some assertions may (at least with some readers) refer to wrong
tombstones entirely, while others assert wrong things about right
tombstones.
* Range tombstones in pre-made sstables (such as those read by
sstable_3_x_test) have deletion time drift, and that now has to be
somehow dealt with.
This patch (which is not split into smaller ones because that would
either generate unreasonable amount of work towards ensuring
bisectability or entail "temporarily" disabling problematic tests,
which is cheating) contains the following changes:
* flat_reader_assertions check range tombstones more carefully, by
accumulating both expected and actually-read range tombstones into
lists and comparing those lists when a partition ends (or when the
assertion object is destroyed).
* flat_reader_assertions::may_produce_tombstones() can take
constraining ck_ranges.
* Both flat_reader_assertions and flat_reader_assertions_v2 can be
instructed to ignore tombstone deletion times, to help with tests that
read pre-made sstables.
* Affected tests are changed to reflect reality. Most changes to
tests make sense; the only one I am not completely sure about is in
test_uncompressed_filtering_and_forwarding_range_tombstones_read.
Fixes#9470
Signed-off-by: Michael Livshin <michael.livshin@scylladb.com>
Currently row marker shadowing the shadowable tombstone is only checked
in `apply(row_marker)`. This means that shadowing will only be checked
if the shadowable tombstone and row marker are set in the correct order.
This at the very least can cause flakyness in tests when a mutation
produced just the right way has a shadowable tombstone that can be
eliminated when the mutation is reconstructed in a different way,
leading to artificial differences when comparing those mutations.
This patch fixes this by checking shadowing in
`apply(shadowable_tombstone)` too, making the shadowing check symmetric.
There is still one vulnerability left: `row_marker& row_marker()`, which
allow overwriting the marker without triggering the corresponding
checks. We cannot remove this overload as it is used by compaction so we
just add a comment to it warning that `maybe_shadow()` has to be manually
invoked if it is used to mutate the marker (compaction takes care of
that). A caller which didn't do the manual check is
mutation_source_test: this patch updates it to use `apply(row_marker)`
instead.
Fixes: #9483
Tests: unit(dev)
Closes#9519
There are 4 flavours of mutation source tests that are all ran
sequentially -- plain, reversed and upgrade/downgrade ones that
check v1<->v2 conversions.
This patch splits them all into individual calls so that some
tests may want to have dedicated cases for each. "By default" they
are all run as they were.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
To ensure all mutation sources uniformly support the current API of
reverse reading: reversed schema and half-reversed slice. This test will
also ensure that once we switch to native-reverse slice, all
mutation-sources will keep on working.
Most test methods log their own name either via testlog.info() or
BOOST_TEST_MESSAGE() so failures can be more easily located. Not all do
however. This commit fixes this and also converts all those using
BOOST_TEST_MESSAGE() for this to testlog.info(), for consistency.
The downgrade_to_v1 didn't reset the state of range tombstone assembler
in case of the calls to next_partition or fast_forward_to, which caused
a situation where the closing range tombstone change is cleared from the
buffer before being emitted, without notifying the assembler. This patch
fixes the behaviour in fast_forward_to as well.
Fixes#9022
