Los pecados de la optimización del rendimiento. Alexander Valyalkin, VictoriaMetrics

El informe está dedicado al tema de la optimización del rendimiento, pero no del todo, sino de los pecados de la optimización del rendimiento (en VictoriaMetrics).

Vídeo

Te diré qué es más tarde. Primero, te contaré un poco sobre mí.

• Soy Alexander Valyalkin Mi apodo es valyala.
• Soy el autor de bibliotecas Go como Fasthttp , Fastjson , Quicktemplate . Estas bibliotecas están optimizadas para la velocidad.
• .
• timeseries VictoriaMetrics.

? , :

• .
• hardware , , .
• – benchmark games. , benchmarks. production.

, . . , .

Fasthttp, fastjson, VictoriaMetrics. Go . Go. .

Fasthttp. Fasthttp – net/http, , .

Fasthttp , :

• .
• HTTP headers.
• slices maps key->value .
• requestCtx.
• DNS .

c . HTTP Go. .

. http . , . , . , . , . . keep-alive, .

? , , / , . . .

, . , HTTP pipelining .

HTTP pipelining – HTTP , .

. . bufio.NewReader bufio.NewWriter. . : , , Write .

, . , , .

pipelining connection. ? – - , . , , , .

? , , . 4 . . . , bufio.Reader, reader 4- .

4 , . , .

. 4 , . , , «flush». . , . .

https://en.wikipedia.org/wiki/HTTP_pipelining#Implementation_status

https://github.com/TechEmpower/FrameworkBenchmarks/issues/4410

.

, HTTP pipelining head of line blocking. - , , HTTP connection , , . , .

. HTTP pipelining . , , HTTP pipelining, . ? HTTP, 2000- , HTTP pipelining, HTTP pipelining. , HTTP pipelining. HTTP 2.0 . , HTTP pipelineing, HTTP 2.0.

HTTP pipelining – , , Techempower benchmarks . Techempower benchmark – , HTTP . , plaintext. 16 pipelining requests . HTTP pipelining fasthttp 2 .

. . , , , .

– HTTP headers.

Fasthttp HTTP headers . HTTP headers. . headers byte slice . byte slice HTTP headers.

Fasthttp, HTTP header . : «Hello, world!» http http headers.

, http headers. , header «X-Forwarded-For», Fasthttp HTTP header.

? , HTTP , HTTP headers .

– , http . , , . .

slices maps. Fasthttp slices key->value go’ map' , , . . , query args, cookies.

, . key->value byte slices.

slice map.

? , slice map – byte slice. kvs – byte slice . capacity , , , . . . slice, . . -. — [:0], , , kv.value, - .

slice map, kv.value byte slice slice map. , , .

slice map. slice map’ . , . .

? , slice maps, , query args cookies, — . slice maps , map Go.

, , slice maps maps. . . slice maps .

, — , . . . query args , slice map , map, map.

. query args , , , slice map – O(N) , . . , slice. , slice map, .

— , slice map . , slice map - , , , slice map , .

— , , slice map, slice map. , slice map . .

– RequestCtx . RequestCtx – , http.ResponseWriter http.Request. , RequestHandler. HTTP .

. . RequestCtx. . ctx.Request. RequestHandler RequestCtx response connection. . . . RequestHandler RequestCtx , , , RequestHandler.

? , RequestCtx. , , . .

, , . API . , - RequestCtx RequestHandler - , , . RequestHandler. , Fasthttp, . . RequestCtx , , , .

, — . RequestCtx - request response body, - . RequestCtx , . .

– DNS. Fasthttp . resolve DNS . Fasthttp DNS , . . resolving. Fasthttp mapping name ip .

, . resolveHost. dnsCache map’a. . , , . , locks. , . , .

? DNS resolving.

– , HTTP , DNS . – Kubernetes, pods, IP-. , , Fasthttp , pod’ . , .

Fasthttp . Fastjson .

Fastjson – encoding/json. , . , .

"" fastjson:

• .

  
  
  

• .

  
  
  

• integers floats.

  
  
  

. Fastjson Parser, JSON. , , .

. Parser.Parse. value. value . . . value Parser. foo. b. b .

JSON. v b, , v p, . . . vv, , .

? , JSON.

– , API . , , , JSON’, .

– , , . . . JSON , , , , 1 , JSON, , 2 , . . . 2 .

– unescaping . Fastjson . escape . escape , . . escape , , .

, , escape , . strings.IndexByte — go’ . .

– , escape .

– , , escape , — , , , . .

– floats integer Fastjson.

, , strconv.

? : « strconv ?». , . . edge cases. . . , strconv . , , , strconv.

– , 0, .

– , - , .

VictoriaMetrics .

. VictoriaMetrics Prometheus remote write API . protobufs.

protobuf , Prometheus. , , . .

. protobuf. timeseries, labels samples. label name value. Sample, , timestamp.

. labels name string. byte slice. , , , name. byte slice data string. , . . string . , , . .

. slice labels, . . slice labels. . label , label , label. capacity , , .

, . , , protobuf.

, . , string byte slice, byte slice , name. byte slice, protobuf, , , name , .

. – .

– sync.Pool.

. strconv.FormatInt Go . Int, nSmalls, 99 100. base ( , ) 10. small, .

? , , 100, .

, , , . . . , , , .

sync.Pool — .

— . , sync.Pool byte slice, byte slice'.

— CPUs. (pipeline). pipeline , , , . , . . pipeline .

. , — . , , Meltdown Spectre, - .

. . , — ? API. . ..

Fasthttp , . . . benchmarks. ? - 10 %, . . 10 % 200 %?

. . , 10 %, . Fasthttp , TechEmpower benchmarks. c Fasthttp, net/http.

Telegram chat: https://t.me/VictoriaMetrics_ru1