netty5/codec-http
Scott Mitchell 93b144b7b4 HttpMethod#valueOf improvement
Motivation:
HttpMethod#valueOf shows up on profiler results in the top set of
results. Since it is a relatively simple operation it can be improved in
isolation.

Modifications:
- Introduce a special case map which assigns each HttpMethod to a unique
index in an array and provides constant time lookup from a hash code
algorithm. When the bucket is matched we can then directly do equality
comparison instead of potentially following a linked structure when
HashMap has hash collisions.

Result:
~10% improvement in benchmark results for HttpMethod#valueOf

Benchmark                                     Mode  Cnt   Score   Error   Units
HttpMethodMapBenchmark.newMapKnownMethods    thrpt   16  31.831 ± 0.928  ops/us
HttpMethodMapBenchmark.newMapMixMethods      thrpt   16  25.568 ± 0.400  ops/us
HttpMethodMapBenchmark.newMapUnknownMethods  thrpt   16  51.413 ± 1.824  ops/us
HttpMethodMapBenchmark.oldMapKnownMethods    thrpt   16  29.226 ± 0.330  ops/us
HttpMethodMapBenchmark.oldMapMixMethods      thrpt   16  21.073 ± 0.247  ops/us
HttpMethodMapBenchmark.oldMapUnknownMethods  thrpt   16  49.081 ± 0.577  ops/us
2017-11-20 11:07:50 -08:00
..
src HttpMethod#valueOf improvement 2017-11-20 11:07:50 -08:00
pom.xml [maven-release-plugin] prepare for next development iteration 2017-11-08 22:36:53 +00:00