From b3eac9f53ff29c1200e501b122a9f6cce52fcc72 Mon Sep 17 00:00:00 2001
From: Harshavardhana <harsha@minio.io>
Date: Mon, 26 Jul 2021 18:28:41 -0700
Subject: [PATCH] simplify warp cleanup stage (#181)

---
 pkg/bench/benchmark.go | 82 ++++++++++++++++--------------------------
 1 file changed, 31 insertions(+), 51 deletions(-)

diff --git a/pkg/bench/benchmark.go b/pkg/bench/benchmark.go
index 4eb72039..dec7ed87 100644
--- a/pkg/bench/benchmark.go
+++ b/pkg/bench/benchmark.go
@@ -21,7 +21,6 @@ import (
 	"context"
 	"fmt"
 	"math"
-	"sync"
 	"time"
 
 	"github.com/minio/minio-go/v7"
@@ -136,59 +135,40 @@ func (c *Common) deleteAllInBucket(ctx context.Context, prefixes ...string) {
 	if len(prefixes) == 0 {
 		prefixes = []string{""}
 	}
-	var wg sync.WaitGroup
-	wg.Add(len(prefixes))
-	for _, prefix := range prefixes {
-		go func(prefix string) {
-			defer wg.Done()
-
-			doneCh := make(chan struct{})
-			defer close(doneCh)
-			cl, done := c.Client()
-			defer done()
-			remove := make(chan minio.ObjectInfo, 1000)
-			errCh := cl.RemoveObjects(ctx, c.Bucket, remove, minio.RemoveObjectsOptions{})
-			defer func() {
-				// Signal we are done
-				close(remove)
-				// Wait for deletes to finish
-				err := <-errCh
-				if err.Err != nil {
-					c.Error(err.Err)
-				}
-			}()
-
-			objects := cl.ListObjects(ctx, c.Bucket, minio.ListObjectsOptions{Prefix: prefix, Recursive: true, WithVersions: c.Versioned})
-			for {
-				select {
-				case obj, ok := <-objects:
-					if !ok {
-						return
-					}
-					if obj.Err != nil {
-						c.Error(obj.Err)
-						continue
-					}
-				sendNext:
-					for {
-						select {
-						case remove <- minio.ObjectInfo{
-							Key:       obj.Key,
-							VersionID: obj.VersionID,
-						}:
-							break sendNext
-						case err := <-errCh:
-							c.Error(err)
-						}
-					}
-				case err := <-errCh:
-					c.Error(err)
+
+	doneCh := make(chan struct{})
+	defer close(doneCh)
+
+	cl, done := c.Client()
+	defer done()
+
+	objectsCh := make(chan minio.ObjectInfo)
+	go func() {
+		defer close(objectsCh)
+		opts := minio.ListObjectsOptions{
+			Recursive:    true,
+			WithVersions: c.Versioned,
+		}
+		for _, prefix := range prefixes {
+			opts.Prefix = prefix
+			for object := range cl.ListObjects(ctx, c.Bucket, opts) {
+				if object.Err != nil {
+					c.Error(object.Err)
+					return
 				}
+				objectsCh <- object
 			}
-		}(prefix)
-	}
-	wg.Wait()
+			console.Infof("\rClearing Prefix %/%q...", c.Bucket, prefix)
+		}
+	}()
 
+	errCh := cl.RemoveObjects(ctx, c.Bucket, objectsCh, minio.RemoveObjectsOptions{})
+	for err := range errCh {
+		if err.Err != nil {
+			c.Error(err.Err)
+			continue
+		}
+	}
 }
 
 // prepareProgress updates preparation progess with the value 0->1.