The central idea of incremental repair is to allow repair participants
to select and repair only a portion of the dataset to speed up the
repair process. All repair participants must utilize an identical
selection method to repair and synchronize the same selected dataset.
There are two primary selection methods: time-based and file-based. The
time-based method selects data within a specified time frame. It is
versatile but it is less efficient because it requires reading all of
the dataset and omitting data beyond the time frame. The file-based
method selects data from unrepaired SSTables and is more efficient
because it allows the entire SSTable to be omitted. This document patch
implements the file-based selection method.
Incremental repair will only be supported for tablet tables; it will not
be supported for vnode tables. On one hand, the legacy vnode is less
important to support. On the other hand, the incremental repair for
vnode is much harder to implement. With vnodes, a SSTalbe could contain
data for multiple vnode ranges. When a given vnode range is repaired,
only a portion of the SSTable is repaired. This complicates the
manipulation of SSTables significantly during both repair and
compaction. With tablets, an entire tablet is repaired so that a
sstable is either fully repaired or not repaired which is a huge
simplification.
This patch uses the repaired_at from sstables::statistics component to
mark a sstable as repaired. It uses a virtual clock as the repair
timestamp, i.e., using a monotonically increasing number for the
repaired_at field of a SSTable and sstables_repaired_at column in
system.tablets table. Notice that when a sstable is not repaired, the
repaired_at field will be set to the default value 0 by default. The
being_repaired in memory field of a SSTable is used to explicitly mark
that a SSTable is being selected. The following variables are used for
incremental repair:
The repaired_at on disk field of a SSTable is used.
- A 64-bit number increases sequentially
The sstables_repaired_at is added to the system.tablets table.
- repaired_at <= sstables_repaired_at means the sstable is repaired
The being_repaired in memory field of a SSTable is added.
- A repair UUID tells which sstable has participated in the repair
Initial test results:
1) Medium dataset results
Node amount: 3
Instance type: i4i.2xlarge
Disk usage per node: ~500GB
Cluster pre-populated with ~500GB of data before starting repairs job.
Results for Repair Timings:
The regular repair run took 210 mins.
Incremental repair 1st run took 183 mins, 2nd and 3rd runs took around 48s
The speedup is: 183 mins / 48s = 228X
2) Small dataset results
Node amount: 3
Instance type: i4i.2xlarge
Disk usage per node: ~167GB
Cluster pre-populated with ~167GB of data before starting the repairs job.
Regular repair 1st run took 110s, 2nd and 3rd runs took 110s.
Incremental repair 1st run took 110 seconds, 2nd and 3rd run took 1.5 seconds.
The speedup is: 110s / 1.5s = 73X
3) Large dataset results
Node amount: 6
Instance type: i4i.2xlarge, 3 racks
50% of base load, 50% read/write
Dataset == Sum of data on each node
Dataset Non-incremental repair (minutes)
1.3 TiB 31:07
3.5 TiB 25:10
5.0 TiB 19:03
6.3 TiB 31:42
Dataset Incremental repair (minutes)
1.3 TiB 24:32
3.0 TiB 13:06
4.0 TiB 5:23
4.8 TiB 7:14
5.6 TiB 3:58
6.3 TiB 7:33
7.0 TiB 6:55
Fixes#22472Closesscylladb/scylladb#24291
* github.com:scylladb/scylladb:
replica: Introduce get_compaction_reenablers_and_lock_holders_for_repair
compaction: Move compaction_reenabler to compaction_reenabler.hh
topology_coordinator: Make rpc::remote_verb_error to warning level
repair: Add metrics for sstable bytes read and skipped from sstables
test.py: Disable incremental for test_tombstone_gc_for_streaming_and_repair
test.py: Add tests for tablet incremental repair
repair: Add tablet incremental repair support
compaction: Add tablet incremental repair support
feature_service: Add TABLET_INCREMENTAL_REPAIR feature
tablet_allocator: Add tablet_force_tablet_count_increase and decrease
repair: Add incremental helpers
sstable: Add being_repaired to sstable
sstables: Add set_repaired_at to metadata_collector
mutation_compactor: Introduce add operator to compaction_stats
tablet: Add sstables_repaired_at to system.tablets table
test: Fix drain api in task_manager_client.py
This patch addes incremental_repair support in compaction.
- The sstables are split into repaired and unrepaired set.
- Repaired and unrepaired set compact sperately.
- The repaired_at from sstable and sstables_repaired_at from
system.tablets table are used to decide if a sstable is repaired or
not.
- Different compactions tasks, e.g., minor, major, scrub, split, are
serialized with tablet repair.
Allow possibly avoiding overlap checks in the case where the source of
the min-live timestamp is known to only contain data which was written
*after* expiry treshold. Expiry treshold is the upper bound of
tombstone.deletion_time that was already expired at the time of
obtaining this expiry treshold value. Meaning that any write originating
from after this point in time, was generated at a time when such
tombstone was already expired. Hence these writes are not relevant for
the purposes of overlap checks with the tombstone and so their min-live
timestamp can be ignored.
This is important for MV workloads, where writes generated now can have
timestamps going far back in time, possibly blocking tombstone GC of
much older [shadowable] tombstones.
We are used to symbols definition being grouped in one .cc file, but a
symbol declaration and definition living in separate modules
(subfolders) is surprising.
Relocate always_gc, never_gc, can_always_purge and can_never_purge to
compaction/compaction.cc, from mutatiobn/mutation_partition.cc. The
declarations of these symbols is in
compaction/compaction_garbage_collector.hh.
Since table_state is a view to a compaction group, it makes sense
to rename it as so.
With upcoming incremental repair, each replica::compaction_group
will be actually two compaction groups, so there will be two
views for each replica::compaction_group.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Compaction is routine and the log messages pollute the log files,
hiding important information.
All the data is available via `nodetool compactionhistory`.
Reduce noise by demoting those log messages to debug level.
One test is adjusted to use debug level for compaction, since it
listens for those messages.
Closesscylladb/scylladb#24949
Print the keyspace.table names, issue trace log messages also
when returning early if tombstone_gc is disabled or
when gc_check_only_compacting_sstables is set.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Closesscylladb/scylladb#24914
Collect tombstone purge statistics like
+ total number of purge attempts
+ number of purge failures due to data overlapping with memtables
+ number of purge failures due to data overlapping with non-compacting
sstables
and expose them in the compaction_stats structure.
Currently, when a max purgeable timestamp is computed, there is no
information where it comes from and how the value was obtained.
Take compaction, if there are memtables or other uncompacting sstables
possibly shadowing data, the timestamp is decreased to ensure a
tombstone is not purged but the caller does not know what that the
timestamp has its value.
In this patch, we extend the return type of max_purgeable_fn to
contain not only a timestamp but also an information on how it was
computed. This information will be required to collect statistics
on tombstone purge failures due to overlapping memtables/uncompacting
sstables that come later in the series.
The compaction_result struct has been extended with the following
properties:
+ id of the shard the compaction took place on
+ type of the compaction
+ time when the compaction started
+ list of sstable files to be compacted
+ list of sstable files generated by compaction
Interval map is very susceptible to quadratic space behavior when
it's flooded with many entries overlapping all (or most of)
intervals, since each such entry will have presence on all
intervals it overlaps with.
A trigger we observed was memtable flush storm, which creates many
small "L0" sstables that spans roughly the entire token range.
Since we cannot rely on insertion order, solution will be about
storing sstables with such wide ranges in a vector (unleveled).
There should be no consequence for single-key reads, since upper
layer applies an additional filtering based on token of key being
queried.
And for range scans, there can be an increase in memory usage,
but not significant because the sstables span an wide range and
would have been selected in the combined reader if the range of
scan overlaps with them.
Anyway, this is a protection against storm of memtable flushes
and shouldn't be the common scenario.
It works both with tablets and vnodes, by adjusting the token
range spanned by compaction group accordingly.
Fixes#23634.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
now that we are allowed to use C++23. we now have the luxury of using
`std::ranges::to`.
in this change, we:
- replace `boost::copy_range` to `std::ranges::to`
- remove unused `#include` of boost headers
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#21880
now that we are allowed to use C++23. we now have the luxury of using
`std::views::transform`.
in this change, we:
- replace `boost::adaptors::transformed` with `std::views::transform`
- use `fmt::join()` when appropriate where `boost::algorithm::join()`
is not applicable to a range view returned by `std::view::transform`.
- use `std::ranges::fold_left()` to accumulate the range returned by
`std::view::transform`
- use `std::ranges::fold_left()` to get the maximum element in the
range returned by `std::view::transform`
- use `std::ranges::min()` to get the minimal element in the range
returned by `std::view::transform`
- use `std::ranges::equal()` to compare the range views returned
by `std::view::transform`
- remove unused `#include <boost/range/adaptor/transformed.hpp>`
- use `std::ranges::subrange()` instead of `boost::make_iterator_range()`,
to feed `std::views::transform()` a view range.
to reduce the dependency to boost for better maintainability, and
leverage standard library features for better long-term support.
this change is part of our ongoing effort to modernize our codebase
and reduce external dependencies where possible.
limitations:
there are still a couple places where we are still using
`boost::adaptors::transformed` due to the lack of a C++23 alternative
for `boost::join()` and `boost::adaptors::uniqued`.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#21700
these unused includes are identified by clang-include-cleaner. after
auditing the source files, all of the reports have been confirmed.
please note, because `mutation/mutation.hh` does not include
`seastar/coroutine/maybe_yield.hh` anymore, and quite a few source
files were relying on this header to bring in the declaration of
`maybe_yield()`, we have to include this header in the places where
this symbol is used. the same applies to `seastar/core/when_all.hh`.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
This PR enables compaction tasks to verify the integrity of the input data through checksum and digest checks. The mechanism for integrity checking was introduced in previous PRs (#20207, #20720) as a built-in functionality of the input streams. This PR integrates this mechanism with compaction. The change applies to all compaction types and covers both compressed and uncompressed SSTables adhering to the 3.x format. If a compaction task reads only part of an SSTable, then only the per-chunk checksums are verified, not the digest.
The PR consists of:
* Changes to mx readers to support integrity checking. The kl readers, considered as compatibility-only, were left unchanged. Also, integrity checking on single-partition reversed reads (`data_consume_reversed_partition()`) remains unsupported by mx readers as this is not used in compaction.
* Changes to `sstable` and `sstable_set` APIs to allow toggling integrity checks for mx readers.
* Activation of integrity checking for all compaction types.
* Tests for all compaction types with corrupted SSTables.
Integrity checks come at a cost. For uncompressed SSTables, the cost is the loading of the CRC and Digest components from disk, and the calculation of checksums and digest from the actual data. For compressed SSTables, checksums are stored in-place and they are being checked already on all reads, so the only extra cost is the loading and calculation of the digest. The measurements show a ~5% regression in compaction performance for uncompressed SSTables, and a negligible regression for compressed SSTables.
Command: `perf-sstable --smp=1 --cpuset=1 --poll-mode --mode=compaction --iterations=1000 --partitions 10000 --sstables=1 --key_size=4096 --num_columns=15 --column_size={32, 1024, 3500, 7000, 14500}`
Uncompressed SSTables:
```
+--------------+-----------------------+----------------------+------------+
| SSTable Size | No Integrity (p/sec) | Integrity (p/sec) | Regression |
+--------------+-----------------------+----------------------+------------+
| 50 MiB | 65175.59 +- 80.82 | 61814.63 +- 72.88 | 5.16% |
| 200 MiB | 41795.10 +- 60.39 | 39686.28 +- 45.05 | 5.05% |
| 500 MiB | 21087.41 +- 30.72 | 20092.93 +- 25.05 | 4.72% |
| 1 GiB | 12781.64 +- 21.77 | 12233.94 +- 21.71 | 4.29% |
| 2 GiB | 6629.99 +- 9.40 | 6377.13 +- 8.28 | 3.81% |
+--------------+-----------------------+----------------------+------------+
```
Compressed SSTables:
```
+--------------+-----------------------+----------------------+------------+
| SSTable Size | No Integrity (p/sec) | Integrity (p/sec) | Regression |
+--------------+-----------------------+----------------------+------------+
| 50 MiB | 53975.05 +- 63.18 | 53825.93 +- 62.28 | 0.28% |
| 200 MiB | 28687.94 +- 26.58 | 28689.41 +- 26.91 | 0% |
| 500 MiB | 13865.35 +- 15.50 | 13790.41 +- 14.88 | 0.54% |
| 1 GiB | 7858.10 +- 7.71 | 7829.75 +- 9.66 | 0.36% |
| 2 GiB | 4023.11 +- 2.43 | 4010.54 +- 2.55 | 0.31% |
+--------------+-----------------------+----------------------+------------+
(p/sec = partitions/sec)
```
Refs #19071.
New feature, no backport is needed.
Closesscylladb/scylladb#21153
* github.com:scylladb/scylladb:
test: Add test for compaction with corrupted SSTables
compaction: Enable integrity checks for all compaction types
sstables: Add integrity option to factories for sstable_set readers
sstables: Add integrity option to sstable::make_reader()
sstables: Add integrity option to mx::make_reader()
sstables: Load checksums and digests in mx full-scan reader
sstables: Add integrity option to data_consume_single_partition()
sstables: Disengage integrity_check from sstable class
sstables: Allow data sources to disable digest check
Compaction tasks create mutation readers to read SSTables from disk.
Each compaction type defines its own reader creation logic by
implementing the pure virtual function `compaction::make_sstable_reader()`.
Modify all implementations of `make_sstable_reader()` to enable
integrity checking on the created readers. This way, all compaction
tasks will be able to detect corruption issues on the compacting
SSTables.
Signed-off-by: Nikos Dragazis <nikolaos.dragazis@scylladb.com>
Split compaction divides the partitions in an existing sstable into two
groups and writes them into two new sstables, which replace the original
one. The partition count from the original sstable is used as an
estimate when writing the new ones, but this estimate is not accurate as
the partitions are split between the two new sstables and each will
contain only a portion of the original partition count. This also causes
the bloom filters to be rebuilt at the end of compaction, as they were
initially built with inaccurate estimates.
Fix this by using a better estimate for the output sstables based on the
token ranges written to them.
Fixes scylladb#20253
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
now that we are allowed to use C++23. we now have the luxury of using
`std::ranges::any_of`.
in this change, we replace `boost::algorithm::any_of` with
`std::ranges::any_of`
to reduce the dependency to boost for better maintainability, and
leverage standard library features for better long-term support.
this change is part of our ongoing effort to modernize our codebase
and reduce external dependencies where possible.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
now that we are allowed to use C++23. we now have the luxury of using
`std::views::values`.
in this change, we:
- replace `boost::adaptors::map_values` with `std::views::values`
- update affected code to work with `std::views::values`
- the places where we use `boost::join()` are not changed, because
we cannot use `std::views::concat` yet. this helper is only
available in C++26.
to reduce the dependency to boost for better maintainability, and
leverage standard library features for better long-term support.
this change is part of our ongoing effort to modernize our codebase
and reduce external dependencies where possible.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#21265
A new field has been added to the compaction_stats structure to hold
collected combined reader statistics. The struct is than used to update
the compaction_history table.
Compaction classes start mutate their internal members to be used
in methods setup_sstable_reader and make_sstable_reader creating
sstable reades that are marked as const.
Remove the const qualifier from these methods. Even though it made
sense initially to mark them as const, it is no longer applicable.
This includes way too much, including <boost/regex.hpp>, which is huge.
Drop includes of adaptors.hpp and replace by what is needed.
Closesscylladb/scylladb#21187
During split prepare phase, there will be more than 1 compaction group with
overlapping token range for a given replica.
Assume tablet 1 has sstable A containing deleted data, and sstable B containing
a tombstone that shadows data in A.
Then split starts:
1) sstable B is split first, and moved from main (unsplit) group to a
split-ready group
2) now compaction runs in split-ready group before sstable A is split
tombstone GC logic today only looks at underlying group, so compaction is step
2 will discard the deleted data in A, since it belongs to another group (the
unsplit one), and so the tombstone can be purged incorrectly.
To fix it, compaction will now work with all uncompacting sstables that belong
to the same replica, since tombstone GC requires all sstables that possibly
contain shadowed data to be available for correct decision to be made.
Fixes https://github.com/scylladb/scylladb/issues/20044.
Branches 6.0, 6.1 and 6.2 are vulnerable, so backport is needed.
Closesscylladb/scylladb#20939
* github.com:scylladb/scylladb:
replica: Fix tombstone GC during tablet split preparation
service: Improve error handling for split
when building scylla with the standard library from GCC-14.2, shipped by
fedora 41, we have following build failure:
```
/home/kefu/.local/bin/clang++ -DDEBUG -DDEBUG_LSA_SANITIZER -DFMT_SHARED -DSANITIZE -DSCYLLA_BUILD_MODE=debug -DSCYLLA_ENABLE_ERROR_INJECTION -DSEASTAR_API_LEVEL=7 -DSEASTAR_DEBUG -DSEASTAR_DEBUG_PROMISE -DSEASTAR_DEBUG_SHARED_PTR -DSEASTAR_DEFAULT_ALLOCATOR -DSEASTAR_LOGGER_COMPILE_TIME_FMT -DSEASTAR_LOGGER_TYPE_STDOUT -DSEASTAR_SCHEDULING_GROUPS_COUNT=16 -DSEASTAR_SHUFFLE_TASK_QUEUE -DSEASTAR_SSTRING -DSEASTAR_TYPE_ERASE_MORE -DXXH_PRIVATE_API -DCMAKE_INTDIR=\"Debug\" -I/home/kefu/dev/scylladb -I/home/kefu/dev/scylladb/build/gen -I/home/kefu/dev/scylladb/seastar/include -I/home/kefu/dev/scylladb/build/seastar/gen/include -I/home/kefu/dev/scylladb/build/seastar/gen/src -isystem /home/kefu/dev/scylladb/abseil -g -Og -g -gz -std=gnu++23 -fvisibility=hidden -Wall -Werror -Wextra -Wno-error=deprecated-declarations -Wimplicit-fallthrough -Wno-c++11-narrowing -Wno-deprecated-copy -Wno-mismatched-tags -Wno-missing-field-initializers -Wno-overloaded-virtual -Wno-unsupported-friend -Wno-unused-parameter -ffile-prefix-map=/home/kefu/dev/scylladb/build=. -march=x86-64-v3 -mpclmul -Xclang -fexperimental-assignment-tracking=disabled -Werror=unused-result -fstack-clash-protection -fsanitize=address -fsanitize=undefined -MD -MT CMakeFiles/scylla-main.dir/Debug/init.cc.o -MF CMakeFiles/scylla-main.dir/Debug/init.cc.o.d -o CMakeFiles/scylla-main.dir/Debug/init.cc.o -c /home/kefu/dev/scylladb/init.cc
In file included from /home/kefu/dev/scylladb/init.cc:12:
In file included from /home/kefu/dev/scylladb/db/config.hh:20:
In file included from /home/kefu/dev/scylladb/locator/abstract_replication_strategy.hh:26:
/home/kefu/dev/scylladb/locator/tablets.hh:410:30: error: unexpected type name 'size_t': expected expression
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ^
/home/kefu/dev/scylladb/locator/tablets.hh:410:23: error: no member named 'irange' in namespace 'boost'
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ~~~~~~~^
/home/kefu/dev/scylladb/locator/tablets.hh:410:38: error: left operand of comma operator has no effect [-Werror,-Wunused-value]
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ^
3 errors generated.
[16/782] Building CXX object CMakeFiles/scylla-main.dir/Debug/keys.cc.o
[17/782] Building CXX object CMakeFiles/scylla-main.dir/Debug/counters.cc.o
[18/782] Building CXX object CMakeFiles/scylla-main.dir/Debug/partition_slice_builder.cc.o
[19/782] Building CXX object CMakeFiles/scylla-main.dir/Debug/mutation_query.cc.o
FAILED: CMakeFiles/scylla-main.dir/Debug/mutation_query.cc.o
/home/kefu/.local/bin/clang++ -DDEBUG -DDEBUG_LSA_SANITIZER -DFMT_SHARED -DSANITIZE -DSCYLLA_BUILD_MODE=debug -DSCYLLA_ENABLE_ERROR_INJECTION -DSEASTAR_API_LEVEL=7 -DSEASTAR_DEBUG -DSEASTAR_DEBUG_PROMISE -DSEASTAR_DEBUG_SHARED_PTR -DSEASTAR_DEFAULT_ALLOCATOR -DSEASTAR_LOGGER_COMPILE_TIME_FMT -DSEASTAR_LOGGER_TYPE_STDOUT -DSEASTAR_SCHEDULING_GROUPS_COUNT=16 -DSEASTAR_SHUFFLE_TASK_QUEUE -DSEASTAR_SSTRING -DSEASTAR_TYPE_ERASE_MORE -DXXH_PRIVATE_API -DCMAKE_INTDIR=\"Debug\" -I/home/kefu/dev/scylladb -I/home/kefu/dev/scylladb/build/gen -I/home/kefu/dev/scylladb/seastar/include -I/home/kefu/dev/scylladb/build/seastar/gen/include -I/home/kefu/dev/scylladb/build/seastar/gen/src -isystem /home/kefu/dev/scylladb/abseil -g -Og -g -gz -std=gnu++23 -fvisibility=hidden -Wall -Werror -Wextra -Wno-error=deprecated-declarations -Wimplicit-fallthrough -Wno-c++11-narrowing -Wno-deprecated-copy -Wno-mismatched-tags -Wno-missing-field-initializers -Wno-overloaded-virtual -Wno-unsupported-friend -Wno-unused-parameter -ffile-prefix-map=/home/kefu/dev/scylladb/build=. -march=x86-64-v3 -mpclmul -Xclang -fexperimental-assignment-tracking=disabled -Werror=unused-result -fstack-clash-protection -fsanitize=address -fsanitize=undefined -MD -MT CMakeFiles/scylla-main.dir/Debug/mutation_query.cc.o -MF CMakeFiles/scylla-main.dir/Debug/mutation_query.cc.o.d -o CMakeFiles/scylla-main.dir/Debug/mutation_query.cc.o -c /home/kefu/dev/scylladb/mutation_query.cc
In file included from /home/kefu/dev/scylladb/mutation_query.cc:12:
In file included from /home/kefu/dev/scylladb/schema/schema_registry.hh:17:
In file included from /home/kefu/dev/scylladb/replica/database.hh:11:
In file included from /home/kefu/dev/scylladb/locator/abstract_replication_strategy.hh:26:
/home/kefu/dev/scylladb/locator/tablets.hh:410:30: error: unexpected type name 'size_t': expected expression
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ^
/home/kefu/dev/scylladb/locator/tablets.hh:410:23: error: no member named 'irange' in namespace 'boost'
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ~~~~~~~^
/home/kefu/dev/scylladb/locator/tablets.hh:410:38: error: left operand of comma operator has no effect [-Werror,-Wunused-value]
410 | return boost::irange<size_t>(0, tablet_count()) | boost::adaptors::transformed([] (size_t i) {
| ^
In file included from /home/kefu/dev/scylladb/mutation_query.cc:12:
In file included from /home/kefu/dev/scylladb/schema/schema_registry.hh:17:
In file included from /home/kefu/dev/scylladb/replica/database.hh:37:
In file included from /home/kefu/dev/scylladb/db/snapshot-ctl.hh:20:
/home/kefu/dev/scylladb/tasks/task_manager.hh:403:54: error: no member named 'irange' in namespace 'boost'
403 | co_await coroutine::parallel_for_each(boost::irange(0u, smp::count), [&tm, id, &res, &func] (unsigned shard) -> future<> {
| ~~~~~~~^
4 errors generated.
```
so let's take the opportunity to switch from `boost::irange` to
`std::views::iota`.
in this change, we:
- switch from boost::irange to std::views::iota for better standard library compatibility
- retain boost::irange where step parameter is used, as std::views::iota doesn't support it
- this change partially modernizes our range usage while maintaining
- existing functionality
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#20924
During split prepare phase, there will be more than 1 compaction group with
overlapping token range for a given replica.
Assume tablet 1 has sstable A containing deleted data, and sstable B containing
a tombstone that shadows data in A.
Then split starts:
1) sstable B is split first, and moved from main (unsplit) group to a
split-ready group
2) now compaction runs in split-ready group before sstable A is split
tombstone GC logic today only looks at underlying group, so compaction is step
2 will discard the deleted data in A, since it belongs to another group (the
unsplit one), and so the tombstone can be purged incorrectly.
To fix it, compaction will now work with all uncompacting sstables that belong
to the same replica, since tombstone GC requires all sstables that possibly
contain shadowed data to be available for correct decision to be made.
Fixes#20044.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Using the standard library is preffered over boost.
In cql3/expr/expression.cc to_sorted_vector got more of a
face-list and was modernized to use also std::unique
and while at it, to move its input range in the uniquely sorted
result vector.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
"crawling" is a little bit obscure in this context. so let's rename this
class to reflect the fact that this reader only reads the entire content
of the sstable.
both crawling reader for kl and mx formats are renamed. also, in order
to be consistent, all "crawling reader" in variable names are updated
as well.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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>
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>
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
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
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
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
The formatted_sstables_list is auxiliary class that collects a bunch of
sstables::to_string(shared_sstable)-generated strings. One of bad side
effects of this helper is that it allocates memory for the vector of
strings.
This patch achieves the same goal with the help of fmt::join() equipped
with transformed boost adaptor.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closesscylladb/scylladb#18160
It was observed that some use cases might append old data constantly to
memtable, blocking GC of expired tombstones.
That's because timestamp of memtable is unconditionally used for
calculating max purgeable, even when the memtable doesn't contain the
key of the tombstone we're trying to GC.
The idea is to treat memtable as we treat L0 sstables, i.e. it will
only prevent GC if it contains data that is possibly shadowed by the
expired tombstone (after checking for key presence and timestamp).
Memtable will usually have a small subset of keys in largest tier,
so after this change, a large fraction of keys containing expired
tombstones can be GCed when memtable contains old data.
Fixes#17599.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Closesscylladb/scylladb#17835
