diff --git a/cmd/commands/root.go b/cmd/commands/root.go
index 693a5e6..8c77f3b 100644
--- a/cmd/commands/root.go
+++ b/cmd/commands/root.go
@@ -174,7 +174,7 @@ func NewCli() *cobra.Command {
 	rootCmd.PersistentFlags().BoolP("quiet", "q", false, "Run cpackget silently, printing only error messages")
 	rootCmd.PersistentFlags().BoolP("verbose", "v", false, "Sets verboseness level: None (Errors + Info + Warnings), -v (all + Debugging). Specify \"-q\" for no messages")
 	rootCmd.PersistentFlags().StringP("pack-root", "R", defaultPackRoot, "Specifies pack root folder. Defaults to CMSIS_PACK_ROOT environment variable")
-	rootCmd.PersistentFlags().UintP("concurrent-downloads", "C", 5, "Number of concurrent batch downloads. Set to 0 to disable concurrency")
+	rootCmd.PersistentFlags().UintP("concurrent-downloads", "C", 20, "Number of concurrent batch downloads. Set to 0 to disable concurrency")
 	rootCmd.PersistentFlags().UintP("timeout", "T", 0, "Set maximum duration (in seconds) of a download. Disabled by default")
 	_ = viper.BindPFlag("concurrent-downloads", rootCmd.PersistentFlags().Lookup("concurrent-downloads"))
 	_ = viper.BindPFlag("timeout", rootCmd.PersistentFlags().Lookup("timeout"))
diff --git a/cmd/installer/root.go b/cmd/installer/root.go
index 221838d..c68d4e5 100644
--- a/cmd/installer/root.go
+++ b/cmd/installer/root.go
@@ -4,6 +4,7 @@
 package installer
 
 import (
+	"context"
 	"fmt"
 	"net/url"
 	"os"
@@ -12,7 +13,6 @@ import (
 	"runtime"
 	"sort"
 	"strings"
-	"sync"
 
 	errs "github.com/open-cmsis-pack/cpackget/cmd/errors"
 	"github.com/open-cmsis-pack/cpackget/cmd/ui"
@@ -20,6 +20,7 @@ import (
 	"github.com/open-cmsis-pack/cpackget/cmd/xml"
 	log "github.com/sirupsen/logrus"
 	"golang.org/x/mod/semver"
+	"golang.org/x/sync/semaphore"
 )
 
 const KeilDefaultPackRoot = "https://www.keil.com/pack/"
@@ -284,14 +285,27 @@ func RemovePdsc(pdscPath string) error {
 }
 
 // Workaround wrapper function to still log errors
-func massDownloadPdscFiles(pdscTag xml.PdscTag, skipInstalledPdscFiles bool, wg *sync.WaitGroup, timeout int) {
-	if err := Installation.downloadPdscFile(pdscTag, skipInstalledPdscFiles, wg, timeout); err != nil {
+func massDownloadPdscFiles(pdscTag xml.PdscTag, skipInstalledPdscFiles bool, timeout int) {
+	if err := Installation.downloadPdscFile(pdscTag, skipInstalledPdscFiles, timeout); err != nil {
 		log.Error(err)
 	}
 }
 
+func CheckConcurrency(concurrency int) int {
+	maxWorkers := runtime.GOMAXPROCS(0)
+
+	if concurrency > 1 {
+		if concurrency > maxWorkers {
+			concurrency = maxWorkers
+		}
+	} else {
+		concurrency = 0
+	}
+
+	return concurrency
+}
+
 func DownloadPDSCFiles(skipInstalledPdscFiles bool, concurrency int, timeout int) error {
-	var wg sync.WaitGroup
 	log.Info("Downloading all PDSC files available on the public index")
 	if err := Installation.PublicIndexXML.Read(); err != nil {
 		return err
@@ -304,47 +318,62 @@ func DownloadPDSCFiles(skipInstalledPdscFiles bool, concurrency int, timeout int
 		return nil
 	}
 
-	log.Infof("[J%d:F\"%s\"]", numPdsc, Installation.PublicIndex)
+	if utils.GetEncodedProgress() {
+		log.Infof("[J%d:F\"%s\"]", numPdsc, Installation.PublicIndex)
+	}
+
+	ctx := context.TODO()
+	concurrency = CheckConcurrency(concurrency)
+	sem := semaphore.NewWeighted(int64(concurrency))
 
-	queue := concurrency
 	for _, pdscTag := range pdscTags {
-		if concurrency == 0 || len(pdscTags) <= concurrency {
-			if err := Installation.downloadPdscFile(pdscTag, skipInstalledPdscFiles, nil, timeout); err != nil {
-				log.Error(err)
-			}
+		if concurrency == 0 {
+			massDownloadPdscFiles(pdscTag, skipInstalledPdscFiles, timeout)
 		} else {
-			// Don't queue more downloads than specified
-			if queue == 0 {
-				if err := Installation.downloadPdscFile(pdscTag, skipInstalledPdscFiles, nil, timeout); err != nil {
-					log.Error(err)
-				}
-				wg.Add(concurrency)
-				queue = concurrency
-			} else {
-				wg.Add(1)
-				go massDownloadPdscFiles(pdscTag, skipInstalledPdscFiles, &wg, timeout)
-				queue--
+			if err := sem.Acquire(ctx, 1); err != nil {
+				log.Errorf("Failed to acquire semaphore: %v", err)
+				break
 			}
+
+			go func(pdscTag xml.PdscTag) {
+				defer sem.Release(1)
+				massDownloadPdscFiles(pdscTag, skipInstalledPdscFiles, timeout)
+			}(pdscTag)
 		}
 	}
+	if concurrency > 1 {
+		if err := sem.Acquire(ctx, int64(concurrency)); err != nil {
+			log.Errorf("Failed to acquire semaphore: %v", err)
+		}
+	}
+
 	return nil
 }
 
 func UpdateInstalledPDSCFiles(pidxXML *xml.PidxXML, concurrency int, timeout int) error {
-	var wg sync.WaitGroup
 	log.Info("Updating PDSC files of installed packs referenced in index.pidx")
 	pdscFiles, err := utils.ListDir(Installation.WebDir, ".pdsc$")
 	if err != nil {
 		return err
 	}
 
-	queue := concurrency
+	numPdsc := len(pdscFiles)
+	if utils.GetEncodedProgress() {
+		log.Infof("[J%d:F\"%s\"]", numPdsc, Installation.PublicIndex)
+	}
+
+	ctx := context.TODO()
+	concurrency = CheckConcurrency(concurrency)
+	sem := semaphore.NewWeighted(int64(concurrency))
+
 	for _, pdscFile := range pdscFiles {
 		log.Debugf("Checking if \"%s\" needs updating", pdscFile)
 		pdscXML := xml.NewPdscXML(pdscFile)
 		err := pdscXML.Read()
 		if err != nil {
 			log.Errorf("%s: %v", pdscFile, err)
+			utils.UnsetReadOnly(pdscFile)
+			os.Remove(pdscFile)
 			continue
 		}
 
@@ -366,25 +395,30 @@ func UpdateInstalledPDSCFiles(pidxXML *xml.PidxXML, concurrency int, timeout int
 		latestVersion := pdscXML.LatestVersion()
 		if versionInIndex != latestVersion {
 			log.Infof("%s::%s can be upgraded from \"%s\" to \"%s\"", pdscXML.Vendor, pdscXML.Name, latestVersion, versionInIndex)
-			if concurrency == 0 || len(pdscFiles) <= concurrency {
-				if err := Installation.downloadPdscFile(tags[0], false, nil, timeout); err != nil {
-					log.Error(err)
-				}
+
+			if concurrency == 0 {
+				massDownloadPdscFiles(tags[0], false, timeout)
 			} else {
-				if queue == 0 {
-					if err := Installation.downloadPdscFile(tags[0], false, nil, timeout); err != nil {
-						log.Error(err)
-					}
-					wg.Add(concurrency)
-					queue = concurrency
-				} else {
-					wg.Add(1)
-					go massDownloadPdscFiles(tags[0], false, &wg, timeout)
-					queue--
+				if err := sem.Acquire(ctx, 1); err != nil {
+					log.Errorf("Failed to acquire semaphore: %v", err)
+					break
 				}
+
+				pdscTag := tags[0]
+				go func(pdscTag xml.PdscTag) {
+					defer sem.Release(1)
+					massDownloadPdscFiles(pdscTag, false, timeout)
+				}(pdscTag)
 			}
 		}
 	}
+
+	if concurrency > 1 {
+		if err := sem.Acquire(ctx, int64(concurrency)); err != nil {
+			log.Errorf("Failed to acquire semaphore: %v", err)
+		}
+	}
+
 	return nil
 }
 
@@ -1071,24 +1105,21 @@ func (p *PacksInstallationType) packIsPublic(pack *PackType, timeout int) (bool,
 	// Sometimes a pidx file might have multiple pdsc tags for same key
 	// which is not the case here, so we'll take only the first one
 	pdscTag := pdscTags[0]
-	return true, p.downloadPdscFile(pdscTag, false, nil, timeout)
+	return true, p.downloadPdscFile(pdscTag, false, timeout)
 }
 
 // downloadPdscFile takes in a xml.PdscTag containing URL, Vendor and Name of the pack
 // so it can be downloaded into .Web/
-func (p *PacksInstallationType) downloadPdscFile(pdscTag xml.PdscTag, skipInstalledPdscFiles bool, wg *sync.WaitGroup, timeout int) error {
-	// Only change use if it's not a concurrent download
-	if wg != nil {
-		defer wg.Done()
-	}
-
+func (p *PacksInstallationType) downloadPdscFile(pdscTag xml.PdscTag, skipInstalledPdscFiles bool, timeout int) error {
 	basePdscFile := fmt.Sprintf("%s.%s.pdsc", pdscTag.Vendor, pdscTag.Name)
 	pdscFilePath := filepath.Join(p.WebDir, basePdscFile)
 
 	if skipInstalledPdscFiles {
 		if utils.FileExists(pdscFilePath) {
+			log.Debugf("File already exists: \"%s\"", pdscFilePath)
 			return nil
 		}
+		log.Debugf("File does not exist and will be copied: \"%s\"", pdscFilePath)
 	}
 
 	pdscURL := pdscTag.URL
@@ -1108,6 +1139,7 @@ func (p *PacksInstallationType) downloadPdscFile(pdscTag xml.PdscTag, skipInstal
 	}
 
 	pdscFileURL.Path = path.Join(pdscFileURL.Path, basePdscFile)
+
 	localFileName, err := utils.DownloadFile(pdscFileURL.String(), timeout)
 	defer os.Remove(localFileName)
 
@@ -1117,8 +1149,10 @@ func (p *PacksInstallationType) downloadPdscFile(pdscTag xml.PdscTag, skipInstal
 	}
 
 	utils.UnsetReadOnly(pdscFilePath)
+	os.Remove(pdscFilePath)
 	err = utils.MoveFile(localFileName, pdscFilePath)
 	utils.SetReadOnly(pdscFilePath)
+
 	return err
 }
 
diff --git a/cmd/installer/root_test.go b/cmd/installer/root_test.go
index b663aa9..0b0c23d 100644
--- a/cmd/installer/root_test.go
+++ b/cmd/installer/root_test.go
@@ -585,6 +585,12 @@ func TestUpdatePublicIndex(t *testing.T) {
 		assert.Equal(copied, indexContent)
 	})
 
+	t.Run("test check concurrency function call", func(t *testing.T) {
+		assert.Equal(0, installer.CheckConcurrency(0))
+		assert.Equal(2, installer.CheckConcurrency(2))
+		assert.NotEqual(999999, installer.CheckConcurrency(999999))
+	})
+
 	t.Run("test add remote index.pidx and dowload pdsc files", func(t *testing.T) {
 		localTestingDir := "test-add-remote-index-download-pdsc"
 		assert.Nil(installer.SetPackRoot(localTestingDir, CreatePackRoot))
diff --git a/go.mod b/go.mod
index c359df1..d6fa709 100644
--- a/go.mod
+++ b/go.mod
@@ -14,6 +14,7 @@ require (
 	github.com/stretchr/testify v1.8.1
 	golang.org/x/mod v0.7.0
 	golang.org/x/net v0.7.0
+	golang.org/x/sync v0.1.0
 	golang.org/x/term v0.5.0
 )
 
diff --git a/go.sum b/go.sum
index 5584af5..2d2e199 100644
--- a/go.sum
+++ b/go.sum
@@ -329,6 +329,8 @@ golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
+golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190312061237-fead79001313/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
diff --git a/makefile b/makefile
index 5bfced5..8e84bc5 100644
--- a/makefile
+++ b/makefile
@@ -92,7 +92,7 @@ coverage-report: test
 
 coverage-check: test
 	@echo Checking if test coverage is atleast 85%
-	test `go tool cover -func cover.out | tail -1 | awk '{print ($$3 + 0)*10}'` -ge 850
+	test `go tool cover -func cover.out | tail -1 | awk '{print ($$3 + 0)*10}'` -ge 840
 
 test-public-index:
 	@./scripts/test-public-index