in in {fmt} before v10, it provides the specialization of `fmt::formatter<..>`
for `std::string_view` as well as the specialization of `fmt::formatter<..>`
for `fmt::string_view` which is an implementation builtin in {fmt} for
compatibility of pre-C++17. and this type is used even if the code is
compiled with C++ stadandard greater or equal to C++17. also, before v10,
the `fmt::formatter<std::string_view>::format()` is defined so it accepts
`std::string_view`. after v10, `fmt::formatter<std::string_view>` still
exists, but it is now defined using `format_as()` machinery, so it's
`format()` method does not actually accept `std::string_view`, it
accepts `fmt::string_view`, as the former can be converted to
`fmt::string_view`.
this is why we can inherit from `fmt::formatter<std::string_view>` and
use `formatter<std::string_view>::format(foo, ctx);` to implement the
`format()` method with {fmt} v9, but we cannot do this with {fmt} v10,
and we would have following compilation failure:
```
FAILED: service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o
/home/kefu/.local/bin/clang++ -DFMT_DEPRECATED_OSTREAM -DFMT_SHARED -DSCYLLA_BUILD_MODE=release -DSEASTAR_API_LEVEL=7 -DSEASTAR_LOGGER_COMPILE_TIME_FMT -DSEASTAR_LOGGER_TYPE_STDOUT -DSEASTAR_SCHEDULING_GROUPS_COUNT=16 -DSEASTAR_SSTRING -DXXH_PRIVATE_API -DCMAKE_INTDIR=\"RelWithDebInfo\" -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 -ffunction-sections -fdata-sections -O3 -g -gz -std=gnu++20 -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-enum-constexpr-conversion -Wno-unused-parameter -ffile-prefix-map=/home/kefu/dev/scylladb=. -march=westmere -mllvm -inline-threshold=2500 -fno-slp-vectorize -U_FORTIFY_SOURCE -Werror=unused-result -MD -MT service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o -MF service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o.d -o service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o -c /home/kefu/dev/scylladb/service/topology_state_machine.cc
/home/kefu/dev/scylladb/service/topology_state_machine.cc:254:41: error: no matching member function for call to 'format'
254 | return formatter<std::string_view>::format(it->second, ctx);
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
/usr/include/fmt/core.h:2759:22: note: candidate function template not viable: no known conversion from 'seastar::basic_sstring<char, unsigned int, 15>' to 'const fmt::basic_string_view<char>' for 1st argument
2759 | FMT_CONSTEXPR auto format(const T& val, FormatContext& ctx) const
| ^ ~~~~~~~~~~~~
```
because the inherited `format()` method actually comes from
`fmt::formatter<fmt::string_view>`. to reduce the confusion, in this
change, we just inherit from `fmt::format<string_view>`, where
`string_view` is actually `fmt::string_view`. this follows
the document at
https://fmt.dev/latest/api.html#formatting-user-defined-types,
and since there is less indirection under the hood -- we do not
use the specialization created by `FMT_FORMAT_AS` which inherit
from `formatter<fmt::string_view>`, hopefully this can improve
the compilation speed a little bit. also, this change addresses
the build failure with {fmt} v10.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#18299
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 `perf_result_with_aio_writes`,
and drop its operator<<.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#17849
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
* scheduling_latency_measurer
* perf_result
and drop their operator<<:s
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
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.
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>
Adds the "--stop-on-error" argument to perf_simple_query. When enabled
(and it is enabled by default), the benchmark will propagate exceptions
if any occur in the tested function. Otherwise, errors will be ignored.
Converts the executor::run_worker() method to a coroutine. This will
allow extending the function in further commits without having to
allocate continuations.
The `time_parallel_ex` function creates a sharded<executor> and uses it
to run the benchmark on multiple shards in parallel. However, if the
benchmarking function throws an exception, the sharded<executor> will be
destroyed without being stopped, which triggers an assertion in
sharded<T> destructor.
This commit makes sure that the executor is stopped before being
destroyed by putting `exec.stop()` into a `seastar::defer`.
to Scylla itself to make it still compile - see below
* seastar 5e863627...96bb3a1b (18):
> install-dependencies: add rocky as a supported distro
> circleci: relax docker limits to allow running with new toolchain
> core: memory: Add memory::free_memory() also in Debug mode
> build: bump up zlib to 1.2.12
> cmake: add FindValgrind.cmake
> Merge 'seastar-addr2line: support sct syslogs' from Benny Halevy
> rpc: lower log level for 'failed to connect' errors
> scripts: Build validation
> perftune.py: remove rx_queue_count from mode condition.
> memory: add attributes to memalign for compatibility with glibc 2.35
> condition-variable: Fix timeout "when" potentially not killing timer
> Merge "tests: perf: measure coroutines performance" from Benny
> Merge: Refine COUNTER metrics
> Revert "Merge: Refine COUNTER metrics"
> reactor: document intentional bitwise-on-bool op in smp_pollfn::poll()
> Merge: Refine COUNTER metrics
> SLES: additionally check irqbalance.service under /usr/lib
> rpc_tester: job_cpu: mark virtual methods override
Changes to Scylla also included in this merge:
1. api: Don't export DERIVEs (Pavel Emelyanov)
Newer seastar doesn't have DERIVE metrics, but does have REAL_COUNTER
one. Teach the collectd getter the change.
(for the record: I don't understand how this endpoing works at all,
there's a HISTOGRAM metrics out there that would be attempted to get
exposed with the v.ui() call which's totally wrong)
2. test: use linux_perf_events.{cc,hh} from Seastar
Seastar now has linux_perf_events.{cc,hh}. Remove Scylla's version
of the same files and use Seastar's. Without this change, Scylla
fails to compile when some source files end up including both
versions and seeing double definitions.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Adds sub-template for time_parallel with templated result type + optional
per-iteration post-process func. Idea is that Res may be a subtype of
perf_result, with additional stats, initiated on init, and post-process
function can fix up and apply stats -> we can add stats to result.
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
seastar::later() was recently deprecated and replaced with two
alternatives: a cheap seastar::yield() and an expensive (but more
powerful) seastar::check_for_io_immediately(), that corresponds to
the original later().
This patch replaces all later() calls with the weaker yield(). In
all cases except one, it's unambiguously correct. In one case
(test/perf scheduling_latency_measurer::stop()) it's not so ambiguous,
since check_for_io_immediately() will additionally force a poll and
so will cause more work to be done (but no additional tasks to be
executed). However, I think that any measurement that relies on
the measuring the work on the last tick to be inaccurate (you need
thousands of ticks to get any amount of confidence in the
measurement) that in the end it doesn't matter what we pick.
Tests: unit (dev)
Closes#9904
Enabling it for each run_worker call will invoke ioctl
PERF_EVENT_IOC_ENABLE in parallel to other workers running
and this may skew the results.
Test: perf_simple_query
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Message-Id: <20210514130542.301168-1-bhalevy@scylladb.com>
Now that executor_stats_snapshot() is a member function, we can move
the capture of _count into invocations into it, capturing all the
stats in one place.
Instructions retired per op is a much more stable than time per op
(inverse throughput) since it isn't much affected by changes in
CPU frequencey or other load on the test system (it's still somewhat
affected since a slower system will run more reactor polls per op).
It's also less indicative of real performance, since it's possible for
fewer inststructions to execute in more time than more instructions,
but that isn't an issue for comparative tests).
This allows incremental changes to the code base to be compared with
more confidence.
I'd like to add an instructions counter which isn't accessible via
a global, so make the snapshot function a member. Out of respect to #1,
define functions for getting the number of allocations and tasks processed,
as they need heavy header files.
Those functions were defined in a header, but not marked inline.
This made including the header from two source files impossible,
as the linker would complain about duplicate symbols.
Rather than making them inline, put them in a new source file
perf.cc as they don't need to be inline.
The plan is to move the unstructured content of tests/ directory
into the following directories of test/:
test/lib - shared header and source files for unit tests
test/boost - boost unit tests
test/unit - non-boost unit tests
test/manual - tests intended to be run manually
test/resource - binary test resources and configuration files
In order to not break git bisect and preserve the file history,
first move most of the header files and resources.
Update paths to these files in .cc files, which are not moved.
