Fixes#28678
If replenish loop exits the sleep condition, with an empty queue,
when "_shutdown" is already set, a waiter might get stuck, unsignalled
waiting for segments, even though we are exiting.
Simply move queue abort to always be done on loop exit.
Closesscylladb/scylladb#28679
Fixes#27992
When doing a commit log oversized allocation, we lock out all other writers by grabbing
the _request_controller semaphore fully (max capacity).
We thereafter assert that the semaphore is in fact zero. However, due to how things work
with the bookkeep here, the semaphore can in fact become negative (some paths will not
actually wait for the semaphore, because this could deadlock).
Thus, if, after we grab the semaphore and execution actually returns to us (task schedule),
new_buffer via segment::allocate is called (due to a non-fully-full segment), we might
in fact grab the segment overhead from zero, resulting in a negative semaphore.
The same problem applies later when we try to sanity check the return of our permits.
Fix is trivial, just accept less-than-zero values, and take same possible ltz-value
into account in exit check (returning units)
Added whitebox (special callback interface for sync) unit test that provokes/creates
the race condition explicitly (and reliably).
Closesscylladb/scylladb#27998
When we come across a segment truncation, this information may
be helpful to determine when the error occurred exactly and
hint at what code path might've led to it.
Closesscylladb/scylladb#27207
Fixes#24346
When reading, we check for each entry and each chunk, if advancing there
will hit EOF of the segment. However, IFF the last chunk being read has
the last entry _exactly_ matching the chunk size, and the chunk ending
at _exactly_ segment size (preset size, typically 32Mb), we did not check
the position, and instead complained about not being able to read.
This has literally _never_ happened in actual commitlog (that was replayed
at least), but has apparently happened more and more in hints replay.
Fix is simple, just check the file position against size when advancing
said position, i.e. when reading (skipping already does).
v2:
* Added unit test
Closesscylladb/scylladb#27236
We include more relevant information for debugging purposes:
the remaining bytes and the size. It might be useful to determine
where exactly an error occurred and help reason about it.
Closesscylladb/scylladb#26486
Replace throwing `protocol_exception` with returning it as a result or an exceptional future in the transport server module. The goal is to improve performance.
Most of the `protocol_exception` throws were made from `fragmented_temporary_buffer` module, by passing `exception_thrower()` to its `read*` methods. `fragmented_temporary_buffer` is changed so that it now accepts an exception creator, not exception thrower. `fragmented_temporary_buffer_concepts::ExceptionCreator` concept replaced `fragmented_temporary_buffer_concepts::ExceptionThrower` and all methods that have been throwing now return failed result of type `utils::result_with_eptr`. This change is then propagated to the callers.
The scope of this patch is `protocol_exception`, so commitlog just calls `.value()` method on the result. If the result failed, that will throw the exception from the result, as defined by `utils::result_with_eptr_throw_policy`. This means that the behavior of commitlog module stays the same.
transport server module handles results gracefully. All the caller functions that return non-future value `T` now return `utils::result_with_eptr<T>`. When the caller is a function that returns a future, and it receives failed result, `make_exception_future(std::move(failed_result).value())` is returned. The rest of the callstack up to the transport server `handle_error` function is already working without throwing, and that's how zero throws is achieved.
cql3 module changes do the same as transport server module.
Benchmark that is not yet merged has commit `67fbe35833e2d23a8e9c2dcb5e04580231d8ec96`, [GitHub diff view](https://github.com/scylladb/scylladb/compare/master...nuivall:scylladb:perf_cql_raw). It uses either read or write query.
Command line used:
```
./build/release/scylla perf-cql-raw --workdir ~/tmp/scylladir --smp 1 --developer-mode 1 --workload write --duration 300 --concurrency 1000 --username cassandra --password cassandra 2>/dev/null
```
The only thing changed across runs is `--workload write`/`--workload read`.
Built and run on `release` target.
<details>
```
throughput:
mean= 36946.04 standard-deviation=1831.28
median= 37515.49 median-absolute-deviation=1544.52
maximum=39748.41 minimum=28443.36
instructions_per_op:
mean= 108105.70 standard-deviation=965.19
median= 108052.56 median-absolute-deviation=53.47
maximum=124735.92 minimum=107899.00
cpu_cycles_per_op:
mean= 70065.73 standard-deviation=2328.50
median= 69755.89 median-absolute-deviation=1250.85
maximum=92631.48 minimum=66479.36
⏱ real=5:11.08 user=2:00.20 sys=2:25.55 cpu=85%
```
```
throughput:
mean= 40718.30 standard-deviation=2237.16
median= 41194.39 median-absolute-deviation=1723.72
maximum=43974.56 minimum=34738.16
instructions_per_op:
mean= 117083.62 standard-deviation=40.74
median= 117087.54 median-absolute-deviation=31.95
maximum=117215.34 minimum=116874.30
cpu_cycles_per_op:
mean= 58777.43 standard-deviation=1225.70
median= 58724.65 median-absolute-deviation=776.03
maximum=64740.54 minimum=55922.58
⏱ real=5:12.37 user=27.461 sys=3:54.53 cpu=83%
```
```
throughput:
mean= 37107.91 standard-deviation=1698.58
median= 37185.53 median-absolute-deviation=1300.99
maximum=40459.85 minimum=29224.83
instructions_per_op:
mean= 108345.12 standard-deviation=931.33
median= 108289.82 median-absolute-deviation=55.97
maximum=124394.65 minimum=108188.37
cpu_cycles_per_op:
mean= 70333.79 standard-deviation=2247.71
median= 69985.47 median-absolute-deviation=1212.65
maximum=92219.10 minimum=65881.72
⏱ real=5:10.98 user=2:40.01 sys=1:45.84 cpu=85%
```
```
throughput:
mean= 38353.12 standard-deviation=1806.46
median= 38971.17 median-absolute-deviation=1365.79
maximum=41143.64 minimum=32967.57
instructions_per_op:
mean= 117270.60 standard-deviation=35.50
median= 117268.07 median-absolute-deviation=16.81
maximum=117475.89 minimum=117073.74
cpu_cycles_per_op:
mean= 57256.00 standard-deviation=1039.17
median= 57341.93 median-absolute-deviation=634.50
maximum=61993.62 minimum=54670.77
⏱ real=5:12.82 user=4:10.79 sys=11.530 cpu=83%
```
This shows ~240 instructions per op increase for reads and ~180 instructions per op increase for writes.
Tests have been run multiple times, with almost identical results. Each run lasted 300 seconds. Number of operations executed is roughly 38k per second * 300 seconds = 11.4m ops.
Update:
I have repeated the benchmark with clean state - reboot computer, put in performance mode, rebuild, closed other apps that might affect CPU and disk usage.
run count: 5 times before and 5 times after the patch
duration: 300 seconds
Average write throughput median before patch: 41155.99
Average write throughput median after patch: 42193.22
Median absolute deviation is also lower now, with values in range 350-550, while the previous runs' values were in range 750-1350.
</details>
Built and run on `release` target.
<details>
./build/release/scylla perf-simple-query --smp 1 --duration 300 --concurrency 1000 --enable-cache false --bypass-cache 2>/dev/null
```
throughput:
mean= 14910.90 standard-deviation=477.72
median= 14956.73 median-absolute-deviation=294.16
maximum=16061.18 minimum=13198.68
instructions_per_op:
mean= 659591.63 standard-deviation=495.85
median= 659595.46 median-absolute-deviation=324.91
maximum=661184.94 minimum=658001.49
cpu_cycles_per_op:
mean= 213301.49 standard-deviation=2724.27
median= 212768.64 median-absolute-deviation=1403.85
maximum=225837.15 minimum=208110.12
⏱ real=5:19.26 user=5:00.22 sys=15.827 cpu=98%
```
./build/release/scylla perf-simple-query --smp 1 --duration 300 --concurrency 1000 --enable-cache false 2>/dev/null
```
throughput:
mean= 93345.45 standard-deviation=4499.00
median= 93915.52 median-absolute-deviation=2764.41
maximum=104343.64 minimum=79816.66
instructions_per_op:
mean= 65556.11 standard-deviation=97.42
median= 65545.11 median-absolute-deviation=71.51
maximum=65806.75 minimum=65346.25
cpu_cycles_per_op:
mean= 34160.75 standard-deviation=803.02
median= 33927.16 median-absolute-deviation=453.08
maximum=39285.19 minimum=32547.13
⏱ real=5:03.23 user=4:29.46 sys=29.255 cpu=98%
```
./build/release/scylla perf-simple-query --smp 1 --duration 300 --concurrency 1000 --enable-cache true 2>/dev/null
```
throughput:
mean= 206982.18 standard-deviation=15894.64
median= 208893.79 median-absolute-deviation=9923.41
maximum=232630.14 minimum=127393.34
instructions_per_op:
mean= 35983.27 standard-deviation=6.12
median= 35982.75 median-absolute-deviation=3.75
maximum=36008.24 minimum=35952.14
cpu_cycles_per_op:
mean= 17374.87 standard-deviation=985.06
median= 17140.81 median-absolute-deviation=368.86
maximum=26125.38 minimum=16421.99
⏱ real=5:01.23 user=4:57.88 sys=0.124 cpu=98%
```
./build/release/scylla perf-simple-query --smp 1 --duration 300 --concurrency 1000 --enable-cache false --bypass-cache 2>/dev/null
```
throughput:
mean= 16198.26 standard-deviation=902.41
median= 16094.02 median-absolute-deviation=588.58
maximum=17890.10 minimum=13458.74
instructions_per_op:
mean= 659752.73 standard-deviation=488.08
median= 659789.16 median-absolute-deviation=334.35
maximum=660881.69 minimum=658460.82
cpu_cycles_per_op:
mean= 216070.70 standard-deviation=3491.26
median= 215320.37 median-absolute-deviation=1678.06
maximum=232396.48 minimum=209839.86
⏱ real=5:17.33 user=4:55.87 sys=18.425 cpu=99%
```
./build/release/scylla perf-simple-query --smp 1 --duration 300 --concurrency 1000 --enable-cache false 2>/dev/null
```
throughput:
mean= 97067.79 standard-deviation=2637.79
median= 97058.93 median-absolute-deviation=1477.30
maximum=106338.97 minimum=87457.60
instructions_per_op:
mean= 65695.66 standard-deviation=58.43
median= 65695.93 median-absolute-deviation=37.67
maximum=65947.76 minimum=65547.05
cpu_cycles_per_op:
mean= 34300.20 standard-deviation=704.66
median= 34143.92 median-absolute-deviation=321.72
maximum=38203.68 minimum=33427.46
⏱ real=5:03.22 user=4:31.56 sys=29.164 cpu=99%
```
./build/release/scylla perf-simple-query --smp 1 --duration 300 --concurrency 1000 --enable-cache true 2>/dev/null
```
throughput:
mean= 223495.91 standard-deviation=6134.95
median= 224825.90 median-absolute-deviation=3302.09
maximum=234859.90 minimum=193209.69
instructions_per_op:
mean= 35981.41 standard-deviation=3.16
median= 35981.13 median-absolute-deviation=2.12
maximum=35991.46 minimum=35972.55
cpu_cycles_per_op:
mean= 17482.26 standard-deviation=281.82
median= 17424.08 median-absolute-deviation=143.91
maximum=19120.68 minimum=16937.43
⏱ real=5:01.23 user=4:58.54 sys=0.136 cpu=99%
```
</details>
Fixes: #24567
This PR is a continuation of #24738 [transport: remove throwing protocol_exception on connection start](https://github.com/scylladb/scylladb/pull/24738). This PR does not solve a burning issue, but is rather an improvement in the same direction. As it is just an enhancement, it should not be backported.
Closesscylladb/scylladb#25408
* github.com:scylladb/scylladb:
test/cqlpy: add protocol exception tests
test/cqlpy: `test_protocol_exceptions.py` refactor message frame building
test/cqlpy: `test_protocol_exceptions.py` refactor duplicate code
transport: replace `make_frame` throw with return result
cql3: remove throwing `protocol_exception`
transport: replace throw in validate_utf8 with result_with_exception_ptr return
transport: replace throwing protocol_exception with returns
utils: add result_with_exception_ptr
test/cqlpy: add unknown compression algorithm test case
Fixes#25709
If we have large allocations, spanning more than one segment, and
the internal segment references from lead to secondary are the
only thing keeping a segment alive, the implicit drop in
discard_unused_segments and orphan_all can cause a recursive call
to discard_unused_segments, which in turn can lead to vector
corruption/crash, or even double free of segment (iterator confusion).
Need to separate the modification of the vector (_segments) from
actual releasing of objects. Using temporaries is the easiest
solution.
To further reduce recursion, we can also do an early clear of
segment dependencies in callbacks from segment release (cf release).
Closesscylladb/scylladb#25719
Replace throwing `protocol_exception` with returning it as a result
or an exceptional future in the transport server module. The goal is
to improve performance.
Most of the `protocol_exception` throws were made from
`fragmented_temporary_buffer` module, by passing `exception_thrower()`
to its `read*` methods. `fragmented_temporary_buffer` is changed so
that it now accepts an exception creator, not exception thrower.
`fragmented_temporary_buffer_concepts::ExceptionCreator` concept replaced
`fragmented_temporary_buffer_concepts::ExceptionThrower` and all
methods that have been throwing now return failed result of type
`utils::result_with_exception_ptr`. This change is then propagated to the callers.
The scope of this patch is `protocol_exception`, so commitlog just calls
`.value()` method on the result. If the result failed, that will throw the
exception from the result, as defined by `utils::result_with_exception_ptr_throw_policy`.
This means that the behavior of commitlog module stays the same.
transport server module handles results gracefully. All the caller functions
that return non-future value `T` now return `utils::result_with_exception_ptr<T>`.
When the caller is a function that returns a future, and it receives
failed result, `make_exception_future(std::move(failed_result).value())`
is returned. The rest of the callstack up to the transport server `handle_error`
function is already working without throwing, and that's how zero throws is
achieved.
Fixes: #24567
We're providing additional information in error messages when throwing
an exception related to data corruption: when a segment is truncated
and when it's content is invalid. That might prove helpful when debugging.
Closesscylladb/scylladb#25190
std::enable_if is obsolete and was replaced with concepts
and constraint.
Replace the std::is_fundamental_v enable_if constraint with
std::integral. The latter is more accurate - std::ntoh()
is not defined for floats, for example. In any case, we only
read integrals in commitlog.
Closesscylladb/scylladb#25226
Fixes#23017
When deleting segments while our footprint is over the limit,
mainly when recycling/deleting segments after replay (recover
boot) we can cause two deletion passes to be running at the same
time. This is because delete is triggered by either
a.) replay release
b.) timer check (explicit)
c.) timer initiated flush callback
where the last one is in fact not even waited for. If we are
considering many files for delete/recycle, we can, due to task
switch, end up considering segments ok to keep, in parallel,
even though one of them should be deleted. The end result
will be us keeping one more segment than should be allowed.
Now, eventually, this should be released, once we do deletion
again, but this can take a while.
Solution is to simply ensure we serialize deletion. This might
cause some delay in processing cycles for recycle, but in
practice, this should never happen when we are in fact under
pressure.
Small unit test included.
The following metrics will be marked with basic_level label:
scylla_commitlog_segments
scylla_commitlog_allocating_segments
scylla_commitlog_unused_segments
scylla_commitlog_alloc
scylla_commitlog_flush
scylla_commitlog_bytes_written
scylla_commitlog_pending_allocations
scylla_commitlog_requests_blocked_memory
scylla_commitlog_flush_limit_exceeded
scylla_commitlog_disk_total_bytes
scylla_commitlog_disk_active_bytes
scylla_commitlog_disk_slack_end_bytes
mark the config parameter --commitlog-use-hard-size-limit as deprecated so the
default 'true' is always used, making the hard limit mandatory.
Fixesscylladb/scylladb#16471Closesscylladb/scylladb#21804
now that we are allowed to use C++23. we now have the luxury of using
`std::views::reverse`.
- replace `boost::adaptors::transformed` with `std::views::transform`
- remove unused `#include <boost/range/adaptor/reversed.hpp>`
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::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
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
the log.hh under the root of the tree was created keep the backward
compatibility when seastar was extracted into a separate library.
so log.hh should belong to `utils` directory, as it is based solely
on seastar, and can be used all subsystems.
in this change, we move log.hh into utils/log.hh to that it is more
modularized. and this also improves the readability, when one see
`#include "utils/log.hh"`, it is obvious that this source file
needs the logging system, instead of its own log facility -- please
note, we do have two other `log.hh` in the tree.
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::keys`.
in this change, we:
- replace `boost::adaptors::map_keys` with `std::views::keys`
- update affected code to work with `std::views::keys`
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#21198
Fixes#20862
With the change in 60af2f3cb2 the bookkeep
for buffer memory was changed subtly, the problem here that we would
shrink buffer size before we after flush use said buffer's size to
decrement the buffer_list_bytes value, previously inc:ed by the full,
allocated size. I.e. we would slowly grow this value instead of adjusting
properly to actual used bytes.
Test included.
Closesscylladb/scylladb#20886
Fixes#20633
Cannot assert on actual request_controller when releasing permit, as the
release, if we have waiters in queue, will subtract some units to hand to them.
Instead assert on permit size + waiter status (and if zero, also controller value)
* v2 - use SCYLLA_ASSERT
Closesscylladb/scylladb#20654
Makes some commitlog options runtime updatable. Most important for this case,
the usage of fragmented entries. Also adds a subscription in database on said
feature, to possibly enable once cluster enables it.
Refs #18161
Yet another approach to dealing with large commitlog submissions.
We handle oversize single mutation by adding yet another entry
type: fragmented. In this case we only add a fragment (aha) of
the data that needs storing into each entry, along with metadata
to correlate and reconstruct the full entry on replay.
Because these fragmented entries are spread over N segments, we
also need to add references from the first segment in a chain
to the subsequent ones. These are released once we clear the
relevant cf_id count in the base.
*
This approach has the downside that due to how serialization etc
works w.r.t. mutations, we need to create an intermediate buffer
to hold the full serialized target entry. This is then incrementally
written into entries of < max_mutation_size, successively requesting
more segments.
On replay, when encountering a fragment chain, the fragment is
added to a "state", i.e. a mapping of currently processing
frag chains. Once we've found all fragments and concatenated
the buffers into a single fragmented one, we can issue a
replay callback as usual.
Note that a replay caller will need to create and provide such
a state object. Old signature replay function remains for tests
and such.
This approach bumps the file format (docs to come).
To ensure "atomicity" we both force syncronization, and should
the whole op fail, we restore segment state (rewinding), thus
discarding data all we wrote.
v2:
* Improve some bookeep, ensure we keep track of segments and flush
properly, to get counter correct
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
If set, any remaining segment that has data older than this threshold
will request flushing, regardless of data pressure. I.e. even a system
where nothing happends will after X seconds flush data to free up the
commit log.
since fedora 38 is EOL. and fedora 39 comes with fmt v10.0.0, also,
we've switched to the build image based on fedora 40, which ships
fmt-devel v10.2.1, there is no need to use fmt::streamed() when
the corresponding format_as() as available.
simpler this way.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#19594
since we've switched almost all callers of the operator<< to {fmt},
let's drop the unused operator<<:s.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#19313
Fixes#18488
Due to the discrepancy between bytes added to CL and bytes written to disk
(due to CRC sector overhead), we fail to account for the proper byte count
when issuing account_memory_usage in allocate (using bytes added) and in
cycle:s notify_memory_written (disk bytes written).
This leads us to slowly, but surely, add to the semaphore all the time.
Eventually rendering it useless.
Also, terminate call would _not_ take any of this into account,
and the chunk overhead there would cause a (smaller) discrepancy
as well.
Fix by simply ensuring that buffer alloc handles its byte usage,
then accounting based on buffer position, not input byte size.
Closesscylladb/scylladb#18489
Fixes#18329
named_file::assign call uses old object "known_size" after a move
of the object. While this is wholly ok, since the attribute accessed
will not be modified/destroyed by the move, it causes warnings in
"tidy" runs, and might confuse or cause real errors should impl. change.
Closesscylladb/scylladb#18337
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 include `fmt/ranges.h` and/or `fmt/std.h`
for formatting the container types, like vector, map
optional and variant using {fmt} instead of the homebrew
formatter based on operator<<.
with this change, the changes adding fmt::formatter and
the changes using ostream formatter explicitly, we are
allowed to drop `FMT_DEPRECATED_OSTREAM` macro.
Refs scylladb#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:
* add `format_as()` for `segment` so we can use it as a fallback
after upgrading to {fmt} v10
* use fmt::streamed() when formatting `segment`, this will be used
the intermediate solution before {fmt} v10 after dropping
`FMT_DEPRECATED_OSTREAM` macro
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#18019
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
* db::commitlog::segment::cf_mark
* db::commitlog::segment_manager::named_file
* db::commitlog::segment_manager::dispose_mode
* db::commitlog::segment_manager::byte_flow<T>
please note, the formatter of `db::commitlog::segment` is not
included in this commit, as we are formatting it in the inline
definition of this class. so we cannot define the specialization
of `fmt::formatter` for this class before its callers -- we'd
either use `format_as()` provided by {fmt} v10, or use `fmt::streamed`.
either way, it's different from the theme of this commit, and we
will handle it in a separated commit.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#17792
This reverts commit 370fbd346c, reversing
changes made to 0912d2a2c6.
This makes scylla-manager mis-interpret the data_file_directories
somehow, issue #17078
This change removes usage of db::config to
get path of commitlog_directory. Instead, it
introduces a new parameter to directly pass
the path to db::commitlog::config::from_db_config().
Refs: scylladb#5626
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 formatters for `db::replay_position`,
and drop its operator<<.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#17014
Add a helper function which returns the minimum replay position
across all existing or future commitlog segments.
Only positions greater or equal to it can be replayed on the next reboot.
We will use this helper in a future patch to garbage collect some cleanup
metadata which refers to replay positions.
Refs #16757
Allows waiting for all previous and pending segment deletes to finish.
Useful if a caller of `discard_completed_segments` (i.e. a memtable
flush target) not only wants to ensure segments are clean and released,
but thoroughly deleted/recycled, and hence no treat to resurrecting
data on crash+restart.
Test included.
Closesscylladb/scylladb#16801
seastar::logger is using the compile-time format checking by default if
compiled using {fmt} 8.0 and up. and it requires the format string to be
consteval string, otherwise we have to use `fmt::runtime()` explicitly.
so adapt the change, let's use the consteval string when formatting
logging messages.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#16612
Fixes#16298
The adjusted buffer position calculation in buffer_position(), introduced in https://github.com/scylladb/scylladb/pull/15494
was in fact broken. It calculated (like previously) a "position" based on diff between
underlying buffer size and ostream size() (i.e. avail), then adjusted this according to
sector overhead rules.
However, the underlying buffer size is in unadjusted terms, and the ostream is adjusted.
The two cannot be compared as such, which means the "positions" we get here are borked.
Luckily for us (sarcasm), the position calculation in replayer made a similar error,
in that it adjusts up current position by one sector overhead to much, leading to us
more or less getting the same, erroneous results in both ends.
However, when/iff one needs to adjust the segment file format further, one might very
quickly realize that this does not work well if, say, one needs to be able to safely
read some extra bytes before first chunk in a segment. Conversely, trying to adjust
this also exposes a latent potential error in the skip mechanism, manifesting here.
Issue fixed by keeping track of the initial ostream capacity for segment buffer, and
use this for position calculation, and in the case of replayer, move file pos adjustment
from read_data() to subroutine (shared with skipping), that better takes data stream
position vs. file position adjustment. In implementaion terms, we first inc the
"data stream" pos (i.e. pos in data without overhead), then adjust for overhead.
Also fix replayer::skip, so that we handle the buffer/pos relation correctly now.
Added test for intial entry position, as well as data replay consistency for single
entry_writer paths.
Fixes#16301
The calculation on whether data may be added is based on position vs. size of incoming data.
However, it did not take sector overhead into account, which lead us to writing past allowed
segment end, which in turn also leads to metrics overflows.
Closesscylladb/scylladb#16302
* github.com:scylladb/scylladb:
commitlog: Fix allocation size check to take sector overhead into account.
commitlog: Fix commitlog_segment::buffer_position() calculation and replay counterpart
Fixes#16301
The calculation on whether data may be added is based on position vs. size of incoming data.
However, it did not take sector overhead into account, which lead us to writing past allowed
segment end, which in turn also leads to metrics overflows.
Fixes#16298
The adjusted buffer position calculation in buffer_position(), introduced in #15494
was in fact broken. It calculated (like previously) a "position" based on diff between
underlying buffer size and ostream size() (i.e. avail), then adjusted this according to
sector overhead rules.
However, the underlying buffer size is in unadjusted terms, and the ostream is adjusted.
The two cannot be compared as such, which means the "positions" we get here are borked.
Luckily for us (sarcasm), the position calculation in replayer made a similar error,
in that it adjusts up current position by one sector overhead to much, leading to us
more or less getting the same, erroneous results in both ends.
However, when/iff one needs to adjust the segment file format further, one might very
quickly realize that this does not work well if, say, one needs to be able to safely
read some extra bytes before first chunk in a segment. Conversely, trying to adjust
this also exposes a latent potential error in the skip mechanism, manifesting here.
Issue fixed by keeping track of the initial ostream capacity for segment buffer, and
use this for position calculation, and in the case of replayer, move file pos adjustment
from read_data() to subroutine (shared with skipping), that better takes data stream
position vs. file position adjustment. In implementaion terms, we first inc the
"data stream" pos (i.e. pos in data without overhead), then adjust for overhead.
Also fix replayer::skip, so that we handle the buffer/pos relation correctly now.
Added test for intial entry position, as well as data replay consistency for single
entry_writer paths.
