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
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
get0() dates back from the days where Seastar futures carried tuples, and
get0() was a way to get the first (and usually only) element. Now
it's a distraction, and Seastar is likely to deprecate and remove it.
Replace with seastar::future::get(), which does the same thing.
We have enabled the command line options without changing a
single line of code, we only had to replace old include
with scylla_test_case.hh.
Next step is to add x-log-compaction-groups options, which will
determine the number of compaction groups to be used by all
instantiations of replica::table.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
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
1. Move tests to test (using singular seems to be a convention
in the rest of the code base)
2. Move boost tests to test/boost, other
(non-boost) unit tests to test/unit, tests which are
expected to be run manually to test/manual.
Update configure.py and test.py with new paths to tests.
