Mike Gerwitz
fc235b7ecc
This adds benchmarking for the memchr crate. It is used primarily by quick-xml at the moment, but the question is whether to rely on it for certain operations for XIR. The benchmarking on an Intel Xeon system shows that memchr and Rust's contains() perform very similarly on small inputs, matching against a single character, and so Rust's built-in should be preferred in that case so that we're using APIs that are familiar to most people. When larger inputs are compared against, there's a greater benefit (a little under ~2x). When comparing against two characters, they are again very close. But look at when we compare two characters against _multiple_ inputs: running 24 tests test large_str:1️⃣:memchr_early_match ... bench: 4,938 ns/iter (+/- 124) test large_str:1️⃣:memchr_late_match ... bench: 81,807 ns/iter (+/- 1,153) test large_str:1️⃣:memchr_non_match ... bench: 82,074 ns/iter (+/- 1,062) test large_str:1️⃣:rust_contains_one_byte_early_match ... bench: 9,425 ns/iter (+/- 167) test large_str:1️⃣:rust_contains_one_byte_late_match ... bench: 123,685 ns/iter (+/- 3,728) test large_str:1️⃣:rust_contains_one_byte_non_match ... bench: 123,117 ns/iter (+/- 2,200) test large_str:1️⃣:rust_contains_one_char_early_match ... bench: 9,561 ns/iter (+/- 507) test large_str:1️⃣:rust_contains_one_char_late_match ... bench: 123,929 ns/iter (+/- 2,377) test large_str:1️⃣:rust_contains_one_char_non_match ... bench: 122,989 ns/iter (+/- 2,788) test large_str:2️⃣:memchr2_early_match ... bench: 5,704 ns/iter (+/- 91) test large_str:2️⃣:memchr2_late_match ... bench: 89,194 ns/iter (+/- 8,546) test large_str:2️⃣:memchr2_non_match ... bench: 85,649 ns/iter (+/- 3,879) test large_str:2️⃣:rust_contains_two_char_early_match ... bench: 66,785 ns/iter (+/- 3,385) test large_str:2️⃣:rust_contains_two_char_late_match ... bench: 2,148,064 ns/iter (+/- 21,812) test large_str:2️⃣:rust_contains_two_char_non_match ... bench: 2,322,082 ns/iter (+/- 22,947) test small_str:1️⃣:memchr_mid_match ... bench: 4,737 ns/iter (+/- 842) test small_str:1️⃣:memchr_non_match ... bench: 5,160 ns/iter (+/- 62) test small_str:1️⃣:rust_contains_one_byte_non_match ... bench: 3,930 ns/iter (+/- 35) test small_str:1️⃣:rust_contains_one_char_mid_match ... bench: 3,677 ns/iter (+/- 618) test small_str:1️⃣:rust_contains_one_char_non_match ... bench: 5,415 ns/iter (+/- 221) test small_str:2️⃣:memchr2_mid_match ... bench: 5,488 ns/iter (+/- 888) test small_str:2️⃣:memchr2_non_match ... bench: 6,788 ns/iter (+/- 134) test small_str:2️⃣:rust_contains_two_char_mid_match ... bench: 6,203 ns/iter (+/- 170) test small_str:2️⃣:rust_contains_two_char_non_match ... bench: 7,853 ns/iter (+/- 713) Yikes. With that said, we won't be comparing against such large inputs short-term. The larger strings (fragments) are copied verbatim, and not compared against---but they _were_ prior to the previous commit that stopped unencoding and re-encoding. So: Rust built-ins for inputs that are expected to be small. |
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| .. | ||
| benches | ||
| build-aux | ||
| src | ||
| tests | ||
| .gitignore | ||
| Cargo.lock | ||
| Cargo.toml | ||
| Makefile.am | ||
| README.md | ||
| autogen.sh | ||
| bootstrap | ||
| configure.ac | ||
| rustfmt.toml | ||
README.md
TAME in Rust (TAMER)
TAME was written to help tame the complexity of developing comparative insurance rating systems. This project aims to tame the complexity and performance issues of TAME itself. TAMER is therefore more tame than TAME.
TAME was originally written in XSLT. For more information about the
project, see the parent README.md.
Building
To bootstrap from the source repository, run ./bootstrap.
To configure the build for your system, run ./configure. To build, run
make. To run tests, run make check.
You may also invoke cargo directly, which make will do for you using
options provided to configure.
Note that the default development build results in terrible runtime performance! See [#Build Flags][] below for instructions on how to generate a release binary.
Build Flags
The environment variable CARGO_BUILD_FLAGS can be used to provide
additional arguments to cargo build when invoked via make. This can be
provided optionally during configure and can be overridden when invoking
make. For example:
# release build
$ ./configure && make CARGO_BUILD_FLAGS=--release
$ ./configure CARGO_BUILD_FLAGS=--release && make
# dev build
$ ./configure && make
$ ./configure CARGO_BUILD_FLAGS=--release && make CARGO_BUILD_FLAGS=
Hacking
This section contains advice for those developing TAMER.
Running Tests
Developers should be using test-driven development (TDD). make check will
run all necessary tests.
Code Format
Rust provides rustfmt that can automatically format code for you. This
project mandates its use and therefore eliminates personal preference in
code style (for better or worse).
Formatting checks are run during make check and, on failure, will output
the diff that would be applied if you ran make fmt (or make fix); this
will run cargo fmt for you (and will use the binaries configured via
configure).
Since developers should be doing test-driven development (TDD) and therefore
should be running make check frequently, the hope is that frequent
feedback on formatting issues will allow developers to quickly adjust their
habits to avoid triggering formatting errors at all.
If you want to automatically fix formatting errors and then run tests:
$ make fmt check
Benchmarking
Benchmarks serve two purposes: external integration tests (which are subject
to module visibility constraints) and actual benchmarking. To run
benchmarks, invoke make bench.
Note that link-time optimizations (LTO) are performed on the binary for benchmarking so that its performance reflects release builds that will be used in production.
The configure script will automatically detect whether the test feature
is unstable (as it was as of the time of writing) and, if so, will
automatically fall back to invoking nightly (by running cargo +nightly bench).
If you do not have nightly, run you install it via rustup install nightly.