root
/
prometheus
mirror of https://github.com/prometheus/prometheus.git
1
0
Fork 0
Code Issues Actions 3 Packages Projects Releases Wiki Activity

Revert "Improving Performance on the API Gzip Handler (#12363)" 

This reverts commit dfae954dc1.

Signed-off-by: Julien Pivotto <roidelapluie@o11y.eu>
This commit is contained in:
Julien Pivotto 2023-06-20 13:39:32 +02:00
parent 652fb03081
commit d19fa62476
4 changed files with 52 additions and 140 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
go.mod
View File

@ -34,7 +34,6 @@ require (
github.com/hetznercloud/hcloud-go v1.45.1
github.com/ionos-cloud/sdk-go/v6 v6.1.7
github.com/json-iterator/go v1.1.12
github.com/klauspost/compress v1.16.5
github.com/kolo/xmlrpc v0.0.0-20220921171641-a4b6fa1dd06b
github.com/linode/linodego v1.17.0
github.com/miekg/dns v1.1.54

2
go.sum
View File

@ -507,8 +507,6 @@ github.com/kisielk/errcheck v1.1.0/go.mod h1:EZBBE59ingxPouuu3KfxchcWSUPOHkagtvW
github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=
github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
github.com/klauspost/compress v1.13.6/go.mod h1:/3/Vjq9QcHkK5uEr5lBEmyoZ1iFhe47etQ6QUkpK6sk=
github.com/klauspost/compress v1.16.5 h1:IFV2oUNUzZaz+XyusxpLzpzS8Pt5rh0Z16For/djlyI=
github.com/klauspost/compress v1.16.5/go.mod h1:ntbaceVETuRiXiv4DpjP66DpAtAGkEQskQzEyD//IeE=
github.com/kolo/xmlrpc v0.0.0-20220921171641-a4b6fa1dd06b h1:udzkj9S/zlT5X367kqJis0QP7YMxobob6zhzq6Yre00=
github.com/kolo/xmlrpc v0.0.0-20220921171641-a4b6fa1dd06b/go.mod h1:pcaDhQK0/NJZEvtCO0qQPPropqV0sJOJ6YW7X+9kRwM=
github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=

68
util/httputil/compression.go
View File

@ -14,11 +14,11 @@
package httputil
import (
"compress/gzip"
"compress/zlib"
"io"
"net/http"
"strings"
"github.com/klauspost/compress/gzhttp"
"github.com/klauspost/compress/zlib"
)
const (
@ -28,28 +28,54 @@ const (
deflateEncoding = "deflate"
)
// Wrapper around http.ResponseWriter which adds deflate compression
type deflatedResponseWriter struct {
// Wrapper around http.Handler which adds suitable response compression based
// on the client's Accept-Encoding headers.
type compressedResponseWriter struct {
http.ResponseWriter
writer *zlib.Writer
writer io.Writer
}
// Writes HTTP response content data.
func (c *deflatedResponseWriter) Write(p []byte) (int, error) {
func (c *compressedResponseWriter) Write(p []byte) (int, error) {
return c.writer.Write(p)
}
// Close Closes the deflatedResponseWriter and ensures to flush all data before.
func (c *deflatedResponseWriter) Close() {
c.writer.Close()
// Closes the compressedResponseWriter and ensures to flush all data before.
func (c *compressedResponseWriter) Close() {
if zlibWriter, ok := c.writer.(*zlib.Writer); ok {
zlibWriter.Flush()
}
if gzipWriter, ok := c.writer.(*gzip.Writer); ok {
gzipWriter.Flush()
}
if closer, ok := c.writer.(io.Closer); ok {
defer closer.Close()
}
}
// Constructs a new deflatedResponseWriter to compress the original writer using 'deflate' compression.
func newDeflateResponseWriter(writer http.ResponseWriter) *deflatedResponseWriter {
return &deflatedResponseWriter{
// Constructs a new compressedResponseWriter based on client request headers.
func newCompressedResponseWriter(writer http.ResponseWriter, req *http.Request) *compressedResponseWriter {
encodings := strings.Split(req.Header.Get(acceptEncodingHeader), ",")
for _, encoding := range encodings {
switch strings.TrimSpace(encoding) {
case gzipEncoding:
writer.Header().Set(contentEncodingHeader, gzipEncoding)
return &compressedResponseWriter{
ResponseWriter: writer,
writer: gzip.NewWriter(writer),
}
case deflateEncoding:
writer.Header().Set(contentEncodingHeader, deflateEncoding)
return &compressedResponseWriter{
ResponseWriter: writer,
writer: zlib.NewWriter(writer),
}
}
}
return &compressedResponseWriter{
ResponseWriter: writer,
writer: writer,
}
}
// CompressionHandler is a wrapper around http.Handler which adds suitable
@ -60,21 +86,7 @@ type CompressionHandler struct {
// ServeHTTP adds compression to the original http.Handler's ServeHTTP() method.
func (c CompressionHandler) ServeHTTP(writer http.ResponseWriter, req *http.Request) {
encodings := strings.Split(req.Header.Get(acceptEncodingHeader), ",")
for _, encoding := range encodings {
switch strings.TrimSpace(encoding) {
case gzipEncoding:
gzhttp.GzipHandler(c.Handler).ServeHTTP(writer, req)
return
case deflateEncoding:
compWriter := newDeflateResponseWriter(writer)
writer.Header().Set(contentEncodingHeader, deflateEncoding)
compWriter := newCompressedResponseWriter(writer, req)
c.Handler.ServeHTTP(compWriter, req)
compWriter.Close()
return
default:
c.Handler.ServeHTTP(writer, req)
return
}
}
}

111
util/httputil/compression_test.go
View File

@ -17,30 +17,23 @@ import (
"bytes"
"compress/gzip"
"compress/zlib"
"encoding/json"
"fmt"
"io"
"net/http"
"net/http/httptest"
"strings"
"testing"
"github.com/stretchr/testify/require"
"github.com/prometheus/prometheus/model/labels"
)
var (
mux *http.ServeMux
server *httptest.Server
respBody = strings.Repeat("Hello World!", 500)
)
func setup() func() {
mux = http.NewServeMux()
server = httptest.NewServer(mux)
return func() {
server.CloseClientConnections()
server.Close()
}
}
@ -48,7 +41,7 @@ func setup() func() {
func getCompressionHandlerFunc() CompressionHandler {
hf := func(w http.ResponseWriter, r *http.Request) {
w.WriteHeader(http.StatusOK)
w.Write([]byte(respBody))
w.Write([]byte("Hello World!"))
}
return CompressionHandler{
Handler: http.HandlerFunc(hf),
@ -74,8 +67,9 @@ func TestCompressionHandler_PlainText(t *testing.T) {
contents, err := io.ReadAll(resp.Body)
require.NoError(t, err, "unexpected error while creating the response body reader")
expected := "Hello World!"
actual := string(contents)
require.Equal(t, respBody, actual, "expected response with content")
require.Equal(t, expected, actual, "expected response with content")
}
func TestCompressionHandler_Gzip(t *testing.T) {
@ -109,7 +103,8 @@ func TestCompressionHandler_Gzip(t *testing.T) {
require.NoError(t, err, "unexpected error while reading the response body")
actual := buf.String()
require.Equal(t, respBody, actual, "unexpected response content")
expected := "Hello World!"
require.Equal(t, expected, actual, "unexpected response content")
}
func TestCompressionHandler_Deflate(t *testing.T) {
@ -143,98 +138,6 @@ func TestCompressionHandler_Deflate(t *testing.T) {
require.NoError(t, err, "unexpected error while reading the response body")
actual := buf.String()
require.Equal(t, respBody, actual, "expected response with content")
}
func Benchmark_compression(b *testing.B) {
client := &http.Client{
Transport: &http.Transport{
DisableCompression: true,
},
}
cases := map[string]struct {
enc string
numberOfLabels int
}{
"gzip-10-labels": {
enc: gzipEncoding,
numberOfLabels: 10,
},
"gzip-100-labels": {
enc: gzipEncoding,
numberOfLabels: 100,
},
"gzip-1K-labels": {
enc: gzipEncoding,
numberOfLabels: 1000,
},
"gzip-10K-labels": {
enc: gzipEncoding,
numberOfLabels: 10000,
},
"gzip-100K-labels": {
enc: gzipEncoding,
numberOfLabels: 100000,
},
"gzip-1M-labels": {
enc: gzipEncoding,
numberOfLabels: 1000000,
},
}
for name, tc := range cases {
b.Run(name, func(b *testing.B) {
tearDown := setup()
defer tearDown()
labels := labels.ScratchBuilder{}
for i := 0; i < tc.numberOfLabels; i++ {
labels.Add(fmt.Sprintf("Name%v", i), fmt.Sprintf("Value%v", i))
}
respBody, err := json.Marshal(labels.Labels())
require.NoError(b, err)
hf := func(w http.ResponseWriter, r *http.Request) {
w.WriteHeader(http.StatusOK)
w.Write(respBody)
}
h := CompressionHandler{
Handler: http.HandlerFunc(hf),
}
mux.Handle("/foo_endpoint", h)
req, _ := http.NewRequest("GET", server.URL+"/foo_endpoint", nil)
req.Header.Set(acceptEncodingHeader, tc.enc)
b.ReportAllocs()
b.ResetTimer()
// Reusing the array to read the body and avoid allocation on the test
encRespBody := make([]byte, len(respBody))
for i := 0; i < b.N; i++ {
resp, err := client.Do(req)
require.NoError(b, err)
require.NoError(b, err, "client get failed with unexpected error")
responseBodySize := 0
for {
n, err := resp.Body.Read(encRespBody)
responseBodySize += n
if err == io.EOF {
break
}
}
b.ReportMetric(float64(responseBodySize), "ContentLength")
resp.Body.Close()
}
client.CloseIdleConnections()
})
}
expected := "Hello World!"
require.Equal(t, expected, actual, "expected response with content")
}