From 2155b46915a4df821405d26f576d9fae9fa5178e Mon Sep 17 00:00:00 2001
From: Zhang Wei <zhangwei555@huawei.com>
Date: Tue, 19 Jul 2016 00:02:41 +0800
Subject: [PATCH 1/2] Enhancement: allow parallel stop

Stop multiple containers in parallel to speed up stop process, allow
maximum 50 parallel stops.

Signed-off-by: Abhinav Dahiya <abhinavdtu2012@gmail.com>
Signed-off-by: Zhang Wei <zhangwei555@huawei.com>
---
 cli/command/container/stop.go  |  8 ++++++--
 cli/command/container/utils.go | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/cli/command/container/stop.go b/cli/command/container/stop.go
index dddb7efa22..2f22fd09a4 100644
--- a/cli/command/container/stop.go
+++ b/cli/command/container/stop.go
@@ -39,11 +39,15 @@ func NewStopCommand(dockerCli *command.DockerCli) *cobra.Command {
 
 func runStop(dockerCli *command.DockerCli, opts *stopOptions) error {
 	ctx := context.Background()
+	timeout := time.Duration(opts.time) * time.Second
 
 	var errs []string
+
+	errChan := parallelOperation(ctx, opts.containers, func(ctx context.Context, id string) error {
+		return dockerCli.Client().ContainerStop(ctx, id, &timeout)
+	})
 	for _, container := range opts.containers {
-		timeout := time.Duration(opts.time) * time.Second
-		if err := dockerCli.Client().ContainerStop(ctx, container, &timeout); err != nil {
+		if err := <-errChan; err != nil {
 			errs = append(errs, err.Error())
 		} else {
 			fmt.Fprintf(dockerCli.Out(), "%s\n", container)
diff --git a/cli/command/container/utils.go b/cli/command/container/utils.go
index 8c993dcce5..7e895834f9 100644
--- a/cli/command/container/utils.go
+++ b/cli/command/container/utils.go
@@ -90,3 +90,35 @@ func getExitCode(dockerCli *command.DockerCli, ctx context.Context, containerID
 	}
 	return c.State.Running, c.State.ExitCode, nil
 }
+
+func parallelOperation(ctx context.Context, cids []string, op func(ctx context.Context, id string) error) chan error {
+	if len(cids) == 0 {
+		return nil
+	}
+	const defaultParallel int = 50
+	sem := make(chan struct{}, defaultParallel)
+	errChan := make(chan error)
+
+	// make sure result is printed in correct order
+	output := map[string]chan error{}
+	for _, c := range cids {
+		output[c] = make(chan error, 1)
+	}
+	go func() {
+		for _, c := range cids {
+			err := <-output[c]
+			errChan <- err
+		}
+	}()
+
+	go func() {
+		for _, c := range cids {
+			sem <- struct{}{} // Wait for active queue sem to drain.
+			go func(container string) {
+				output[container] <- op(ctx, container)
+				<-sem
+			}(c)
+		}
+	}()
+	return errChan
+}

From f1dda4395eb52eaeca8f9a1c76c2e2c3e6532490 Mon Sep 17 00:00:00 2001
From: Zhang Wei <zhangwei555@huawei.com>
Date: Mon, 12 Sep 2016 17:21:08 +0800
Subject: [PATCH 2/2] Add parallel operation support for pause/unpause

Support parallel pause/unpause

Signed-off-by: Zhang Wei <zhangwei555@huawei.com>
---
 cli/command/container/pause.go   | 3 ++-
 cli/command/container/unpause.go | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/cli/command/container/pause.go b/cli/command/container/pause.go
index 0cc5b351ba..6817cf60eb 100644
--- a/cli/command/container/pause.go
+++ b/cli/command/container/pause.go
@@ -34,8 +34,9 @@ func runPause(dockerCli *command.DockerCli, opts *pauseOptions) error {
 	ctx := context.Background()
 
 	var errs []string
+	errChan := parallelOperation(ctx, opts.containers, dockerCli.Client().ContainerPause)
 	for _, container := range opts.containers {
-		if err := dockerCli.Client().ContainerPause(ctx, container); err != nil {
+		if err := <-errChan; err != nil {
 			errs = append(errs, err.Error())
 		} else {
 			fmt.Fprintf(dockerCli.Out(), "%s\n", container)
diff --git a/cli/command/container/unpause.go b/cli/command/container/unpause.go
index c3635db555..c4d8d4841e 100644
--- a/cli/command/container/unpause.go
+++ b/cli/command/container/unpause.go
@@ -35,8 +35,9 @@ func runUnpause(dockerCli *command.DockerCli, opts *unpauseOptions) error {
 	ctx := context.Background()
 
 	var errs []string
+	errChan := parallelOperation(ctx, opts.containers, dockerCli.Client().ContainerUnpause)
 	for _, container := range opts.containers {
-		if err := dockerCli.Client().ContainerUnpause(ctx, container); err != nil {
+		if err := <-errChan; err != nil {
 			errs = append(errs, err.Error())
 		} else {
 			fmt.Fprintf(dockerCli.Out(), "%s\n", container)