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								// Copyright 2018 The go-ethereum Authors
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								// This file is part of go-ethereum.
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								//
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								// go-ethereum is free software: you can redistribute it and/or modify
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								// it under the terms of the GNU General Public License as published by
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								// the Free Software Foundation, either version 3 of the License, or
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								// (at your option) any later version.
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								//
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								// go-ethereum is distributed in the hope that it will be useful,
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								// but WITHOUT ANY WARRANTY; without even the implied warranty of
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								// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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								// GNU General Public License for more details.
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								//
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								// You should have received a copy of the GNU General Public License
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								// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
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								package main
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								import (
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									"bytes"
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									"fmt"
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									"math/rand"
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									"time"
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									"github.com/ethereum/go-ethereum/log"
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									"github.com/ethereum/go-ethereum/metrics"
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									"github.com/ethereum/go-ethereum/swarm/testutil"
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									"github.com/pborman/uuid"
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									cli "gopkg.in/urfave/cli.v1"
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								)
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								type uploadResult struct {
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									hash   string
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									digest []byte
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								}
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								func slidingWindowCmd(ctx *cli.Context) error {
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									errc := make(chan error)
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									go func() {
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										errc <- slidingWindow(ctx)
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									}()
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									err := <-errc
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									if err != nil {
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										metrics.GetOrRegisterCounter(fmt.Sprintf("%s.fail", commandName), nil).Inc(1)
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									}
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									return err
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								}
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								func slidingWindow(ctx *cli.Context) error {
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									var hashes []uploadResult //swarm hashes of the uploads
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									nodes := len(hosts)
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									log.Info("sliding window test started", "nodes", nodes, "filesize(kb)", filesize, "timeout", timeout)
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									uploadedBytes := 0
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									networkDepth := 0
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									errored := false
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								outer:
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									for {
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										seed = int(time.Now().UTC().UnixNano())
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										log.Info("uploading to "+httpEndpoint(hosts[0])+" and syncing", "seed", seed)
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										t1 := time.Now()
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										randomBytes := testutil.RandomBytes(seed, filesize*1000)
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										hash, err := upload(randomBytes, httpEndpoint(hosts[0]))
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										if err != nil {
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											log.Error(err.Error())
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											return err
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										}
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										metrics.GetOrRegisterResettingTimer("sliding-window.upload-time", nil).UpdateSince(t1)
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										metrics.GetOrRegisterGauge("sliding-window.upload-depth", nil).Update(int64(len(hashes)))
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										fhash, err := digest(bytes.NewReader(randomBytes))
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										if err != nil {
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											log.Error(err.Error())
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											return err
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										}
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										log.Info("uploaded successfully", "hash", hash, "digest", fmt.Sprintf("%x", fhash), "wait for sync", syncDelay)
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										hashes = append(hashes, uploadResult{hash: hash, digest: fhash})
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										if syncDelay {
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											waitToSync()
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										}
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										uploadedBytes += filesize * 1000
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										q := make(chan struct{}, 1)
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										d := make(chan struct{})
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										defer close(q)
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										defer close(d)
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										for i, v := range hashes {
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											timeoutC := time.After(time.Duration(timeout) * time.Second)
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											errored = false
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										task:
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											for {
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												select {
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												case q <- struct{}{}:
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													go func() {
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														var start time.Time
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														done := false
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														for !done {
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															log.Info("trying to retrieve hash", "hash", v.hash)
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															idx := 1 + rand.Intn(len(hosts)-1)
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															ruid := uuid.New()[:8]
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															start = time.Now()
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															// fetch hangs when swarm dies out, so we have to jump through a bit more hoops to actually
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															// catch the timeout, but also allow this retry logic
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															err := fetch(v.hash, httpEndpoint(hosts[idx]), v.digest, ruid)
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															if err != nil {
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																log.Error("error fetching hash", "err", err)
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																continue
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															}
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															done = true
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														}
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														metrics.GetOrRegisterResettingTimer("sliding-window.single.fetch-time", nil).UpdateSince(start)
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														d <- struct{}{}
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													}()
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												case <-d:
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													<-q
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													break task
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												case <-timeoutC:
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													errored = true
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													log.Error("error retrieving hash. timeout", "hash idx", i)
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													metrics.GetOrRegisterCounter("sliding-window.single.error", nil).Inc(1)
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													break outer
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												default:
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							 | 
							
								
							 | 
							
								
							 | 
							
							
												}
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
											}
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
											networkDepth = i
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
											metrics.GetOrRegisterGauge("sliding-window.network-depth", nil).Update(int64(networkDepth))
							 | 
						
					
						
							
								
									
										
										
										
											2019-03-05 23:43:05 +07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
											log.Info("sliding window test successfully fetched file", "currentDepth", networkDepth)
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
											// this test might take a long time to finish - but we'd like to see metrics while they accumulate and not just when
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
											// the test finishes. therefore emit the metrics on each iteration
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
											emitMetrics(ctx)
							 | 
						
					
						
							
								
									
										
										
										
											2019-01-30 15:46:44 +07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
										}
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
									}
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
									log.Info("sliding window test finished", "errored?", errored, "networkDepth", networkDepth, "networkDepth(kb)", networkDepth*filesize)
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
									log.Info("stats", "uploadedFiles", len(hashes), "uploadedKb", uploadedBytes/1000, "filesizeKb", filesize)
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
									return nil
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								}
							 |