Add benchmark README and latest numbers

[mayurkale22]

Which problem is this PR solving?

• The first iteration of README.md, please contribute or suggest missing things.

[mayurkale22]

Below line#59 depends on this.

[codecov-io]

Codecov Report

Merging #689 into master will decrease coverage by 1.57%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #689      +/-   ##
==========================================
- Coverage    92.7%   91.12%   -1.58%     
==========================================
  Files         227      225       -2     
  Lines       10346    10541     +195     
  Branches      934      965      +31     
==========================================
+ Hits         9591     9606      +15     
- Misses        755      935     +180

Impacted Files	Coverage Δ
...ckages/opentelemetry-exporter-jaeger/src/jaeger.ts	90.56% <100%> (+0.56%)	⬆️
packages/opentelemetry-core/test/utils/url.test.ts	50% <0%> (-50%)	⬇️
...pentelemetry-core/test/internal/validators.test.ts	50% <0%> (-50%)	⬇️
...elemetry-core/test/trace/spancontext-utils.test.ts	55.55% <0%> (-44.45%)	⬇️
...lemetry-core/test/trace/ProbabilitySampler.test.ts	56.52% <0%> (-43.48%)	⬇️
...s/opentelemetry-core/test/trace/NoopTracer.test.ts	60% <0%> (-40%)	⬇️
...s/opentelemetry-core/test/context/B3Format.test.ts	63.39% <0%> (-36.61%)	⬇️
...ges/opentelemetry-core/test/trace/NoopSpan.test.ts	63.63% <0%> (-36.37%)	⬇️
...s/opentelemetry-core/test/trace/tracestate.test.ts	65.06% <0%> (-34.94%)	⬇️
...ntelemetry-core/test/trace/NoRecordingSpan.test.ts	71.42% <0%> (-28.58%)	⬇️
... and 40 more

[dyladan]

Can you add a noop tracer setup?

[dyladan]

The difference between NodeTracerRegistry and BasicTracerRegistry is only in setup (1 time per application) and the getTracer call (1 time per plugin). The benchmarks themselves don't do either of these things so there is no actual difference between them. In my opinion, the setups it makes sense to keep are the BasicTracerRegistry and the NoopTracerRegistry.

[obecny]

so far npm run bench fails for me anyway, does it work for you ?

[OlivierAlbertini]

so far npm run bench fails for me anyway, does it work for you ?

Indeed, after npm install at the root project

➜ npm run bench 
npm info it worked if it ends with ok
npm info using npm@6.10.2
npm info using node@v10.9.0
npm info lifecycle opentelemetry-base@0.3.2~prebench: opentelemetry-base@0.3.2
npm info lifecycle opentelemetry-base@0.3.2~bench: opentelemetry-base@0.3.2

> opentelemetry-base@0.3.2 bench /Users/.../apps/.../opentelemetry-js
> node benchmark


internal/modules/cjs/loader.js:583
    throw err;
    ^

Error: Cannot find module '@opentelemetry/core'
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:581:15)
    at Function.Module._load (internal/modules/cjs/loader.js:507:25)
    at Module.require (internal/modules/cjs/loader.js:637:17)
    at require (internal/modules/cjs/helpers.js:20:18)
    at Object.<anonymous> (/Users/.../apps/.../opentelemetry-js/benchmark/tracer.js:4:23)
    at Module._compile (internal/modules/cjs/loader.js:689:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)
    at Module.load (internal/modules/cjs/loader.js:599:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)
    at Function.Module._load (internal/modules/cjs/loader.js:530:3)
child_process.js:640
    throw err;
    ^

Error: Command failed: node benchmark/tracer
    at checkExecSyncError (child_process.js:600:11)
    at execSync (child_process.js:637:13)
    at exec (/Users/.../apps/.../opentelemetry-js/benchmark/index.js:4:21)
    at Object.<anonymous> (/Users/.../apps/.../opentelemetry-js/benchmark/index.js:6:1)
    at Module._compile (internal/modules/cjs/loader.js:689:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)
    at Module.load (internal/modules/cjs/loader.js:599:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)
    at Function.Module._load (internal/modules/cjs/loader.js:530:3)
    at Function.Module.runMain (internal/modules/cjs/loader.js:742:12)
npm info lifecycle opentelemetry-base@0.3.2~bench: Failed to exec bench script

[dyladan]

I would suggest the following:

• having the benchmark load the packages directly by file path so that we can avoid having to deal with dependency management in the benchmarks
• making the number of runs configurable per-file so that the formatters, which are very fast, can run more times than the tracers
• instead of distinguishing between web and node tracers (there is no distinction to the actual tracer anymore), distinguish between the noop tracer, tracer without span process, and tracer with each span processor.

Made mayurkale22#1 so you can see what i'm talking about.

[obecny]

For web it will be nice to be able to run benchmark in few popular browsers as sometimes the certain browser might be really slow. For that we might use services like https://www.browserstack.com/ for example

[dyladan]

Please put the latest numbers in the README after you merged my sub-PR

[mayurkale22]

Please put the latest numbers in the README after you merged my sub-PR

Done.

[mayurkale22]

so far npm run bench fails for me anyway, does it work for you ?

@dyladan made some changes to the PR and npm run bench is also working now. @obecny Can you please verify and approve the PR.