Your hard drive is getting full. Nothing slows down a Mac more than having too much on your hard. Volume optimisations. We’ve identified bind-mounts can be slow on Mac.One of the biggest performance optimisations you can make, is altering the guarantee that file system data is perfectly replicated to the host and container. Docker defaults to a consistent guarantee that the host and containers file system reflect each other.
For about two years, I’ve wanted to use Docker for local development. Hypothetically, it offers all the benefits of virtualized development environments like Vagrant (stable, re-creatable, isolated, etc.) but requires fewer resources.
Working at a consultancy, sometimes I need to switch back and forth between multiple projects in a day. Spinning a full VM up and down can take a while. Alternatively, running two or more virtual machines at once can eat up all of my computer’s resources.
While I’d been interested in Docker for a while, I hadn’t had the time and energy to really dive into it. Then I went to DockerCon this April, which finally gave me enough momentum to figure out how to integrate it into my development workflow.
Sharing is Caring (About File IO Speed)
I suspected—correctly—that Docker would fall prey to some of the same shortcomings as Vagrant. Specifically, I am thinking of the speed of shared volumes. Generally speaking, sharing files between MacOS and a virtual OS on a hypervisor breaks down when too many reads or writes are required in a short amount of time. This may be due to running asset pipelines like those of Rails or Ember that generate tons of temporary files.
Most sharing systems (VirtualBox, NFS) do not support ignoring subdirectories. That wouldn’t be so bad, except that many framework tools do not let you configure the location of dependencies and temp directories. I’m looking at you, Ember.
What’s a Developer to Do?
Generally, this problem leads you to one of the following solutions:
- Doing the reads/writes on the host and pushing the finished output into the container/guest
- Using SSHFS to share files out of the container/guest back to the host
- Using rsync or similar utilities that have to run separately but allow for ignoring subdirectories
- Editing the code in the container via SSH plus Vim or Emacs
Why I Wasn’t Satisfied
Each of the solutions mentioned above has drawbacks:
- Building on the host: You risk drift between your host machine and the development environment, and you have to install all the tooling on your host for all versions used by your projects.
- SSHFS: Personally, I’ve found this very flaky, especially if your computer goes to sleep. Searching the shared files from the host can be slow, to say nothing of editor tooling with compiled languages like TypeScript or C#. Additionally, having the code “live” in something as ephemeral as a Docker container seems like a bad idea.
- rsync: I think it’s annoying to have to run another process. Plus, rsync is one way, so changes on the container will not be reflected on the host (e.g. output from Rails generators). Of course, there are other options in this space such as Unison, that are bi-directional.
- Editing in the container: I miss some of the features/layout of editors like VS Code or Atom. And you’ve got to find a way to get all your favorite Vim or Emacs configs into the container. This solution also suffers from the same drawbacks as SSHFS with regard to code living the container.
Of course, there’s one option for Docker that sidesteps this whole issue. You could develop in a windowed Linux environment (native or virtual) that functions as the Docker machine. File sharing between the Docker machine and containers is extremely fast. But if you want to stay in MacOS and use Docker, I have a few tips to make your life better.
Docker-sync and Upcoming Changes
Docker For Mac Slow Download Safari
Docker-sync is a very handy Ruby gem that makes it easy to use rsync or unison file sharing with Docker. Rsync and unison allow you to exclude subdirectories, so you can ignore ./tmp, ./node_modules, ./dist, and so on. This gem even takes file sharing a step farther, using Docker volumes in conjunction with rsync/unison for optimum performance.
For instance, in my Rails project’s Dockerfile, I
ADD
just enough files to run bundle install
, then I mount in my source directory via docker-compose
. It’s important to remember that this wipes whatever you ADD
ed during the build. So, for example, if you add a gem to your Gemfile and bundle install
, you’ll eventually need to rebuild your base image. Generally, you should just run
docker-compose up --build
to make sure your image doesn’t get too out of date. Also, if you are using rsync, you’ll need to docker cp
the automatically updated Gemfile.lock back out of the container to the host.Docker is working on some improvements to Docker for Mac that may significantly improve the speed of reads and writes–provided you are okay with eventual consistency. The improvements for reading speed are coming soon, but last I checked, the improvements for writing speed (the more common problem in my experience) are still a ways out.
Slow IO±It’s More than Just Volume Mounting
Another disk IO problem you might run into using Docker for Mac is slow database speed. I noticed this when our Rails database migrations took around 10 times longer to run on Docker for Mac versus native.
After a bit of searching, I found this script on a GitHub issue. Running the script brought performance back to approximately the same as native. Hopefully, this issue will be fixed soon, and the script will be unnecessary.
I Still Want to Docker All the Things
Developing in Docker isn’t perfect, but the workflow is improving rapidly. So is the whole Docker ecosystem.
Multi-stage builds are going to streamline the process of creating development and production images. The Moby project will help developers pick and choose what parts of the tools they want to use.
I have faith that in a year or two, the file sharing/disk IO speed problems will be a distant memory. The container revolution is just getting started.
If you’re at all on the fence, I encourage you to try out Docker. For me, it wasn’t until I ported an existing project into Docker that I began to understand the big picture.
Estimated reading time: 6 minutes Vivavideo pro free download for mac. Docker Desktop for Mac is the Community version of Docker for Mac.You can download Docker Desktop for Mac from Docker Hub.
By downloading Docker Desktop, you agree to the terms of the Docker Software End User License Agreement and the Docker Data Processing Agreement.
What to know before you install
README FIRST for Docker Toolbox and Docker Machine users
If you are already running Docker on your machine, first readDocker Desktop for Mac vs. Docker Toolbox to understand theimpact of this installation on your existing setup, how to set your environmentfor Docker Desktop on Mac, and how the two products can coexist.
Docker For Mac Uninstall
Relationship to Docker Machine: Installing Docker Desktop on Mac does not affect machines you created with Docker Machine. You have the option to copy containers and images from your local
default
machine (if one exists) to the Docker Desktop HyperKit VM. Whenyou are running Docker Desktop, you do not need Docker Machine nodes running locally (or anywhere else). With Docker Desktop, you have a new, nativevirtualization system running (HyperKit) which takes the place of theVirtualBox system. To learn more, see Docker Desktop for Mac vs. Docker Toolbox.System requirements
Your Mac must meet the following requirements to successfully install Docker Desktop:
- Mac hardware must be a 2010 or a newer model, with Intel’s hardware support for memory management unit (MMU) virtualization, including Extended Page Tables (EPT) and Unrestricted Mode. You can check to see if your machine has this support by running the following command in a terminal:
sysctl kern.hv_support
If your Mac supports the Hypervisor framework, the command printskern.hv_support: 1
. - macOS must be version 10.13 or newer. That is, Catalina, Mojave, or High Sierra. We recommend upgrading to the latest version of macOS.If you experience any issues after upgrading your macOS to version 10.15, you must install the latest version of Docker Desktop to be compatible with this version of macOS.Note: Docker supports Docker Desktop on the most recent versions of macOS. That is, the current release of macOS and the previous two releases. Docker Desktop currently supports macOS Catalina, macOS Mojave, and macOS High Sierra.As new major versions of macOS are made generally available, Docker stops supporting the oldest version and support the newest version of macOS (in addition to the previous two releases).
- At least 4 GB of RAM.
- VirtualBox prior to version 4.3.30 must not be installed as it is not compatible with Docker Desktop.
What’s included in the installer
The Docker Desktop installation includes Docker Engine, Docker CLI client, Docker Compose, Notary, Kubernetes, and Credential Helper.
Install and run Docker Desktop on Mac
- Double-click
Docker.dmg
to open the installer, then drag the Docker icon to the Applications folder. - Double-click
Docker.app
in the Applications folder to start Docker. (In the example below, the Applications folder is in “grid” view mode.)The Docker menu in the top status bar indicates that Docker Desktop is running, and accessible from a terminal.If you’ve just installed the app, Docker Desktop launches the onboarding tutorial. The tutorial includes a simple exercise to build an example Docker image, run it as a container, push and save the image to Docker Hub. - Click the Docker menu () to seePreferences Dj mixer professional for win serial key. and other options.
- Select About Docker to verify that you have the latest version.
Congratulations! You are now successfully running Docker Desktop.
If you would like to rerun the tutorial, go to the Docker Desktop menu and select Learn.
Uninstall Docker Desktop
Docker For Mac Slow Downloads
To unistall Docker Desktop from your Mac:
- From the Docker menu, select Troubleshoot and then select Uninstall.
- Click Uninstall to confirm your selection.
Note: Uninstalling Docker Desktop will destroy Docker containers and images local to the machine and remove the files generated by the application.
Switch between Stable and Edge versions
Docker Desktop allows you to switch between Stable and Edge releases. However, you can only have one version of Docker Desktop installed at a time. Switching between Stable and Edge versions can destabilize your development environment, particularly in cases where you switch from a newer (Edge) channel to an older (Stable) channel.
For example, containers created with a newer Edge version of Docker Desktop maynot work after you switch back to Stable because they may have been createdusing Edge features that aren’t in Stable yet. Keep this in mind asyou create and work with Edge containers, perhaps in the spirit of a playgroundspace where you are prepared to troubleshoot or start over.
Experimental features are turned on by default on Edge releases. However, when you switch from a Stable to an Edge release, you must turn on the experimental features flag to access experimental features. From the Docker Desktop menu, click Preferences > Command Line and then turn on the Enable experimental features toggle. Click Apply & Restart for the changes to take effect.
To safely switch between Edge and Stable versions, ensure you save images and export the containers you need, then uninstall the current version before installing another. For more information, see the section Save and Restore data below.
Save and restore data
You can use the following procedure to save and restore images and container data. For example, if you want to switch between Edge and Stable, or to reset your VM disk:
- Use
docker save -o images.tar image1 [image2 ..]
to save any images you want to keep. See save in the Docker Engine command line reference. - Use
docker export -o myContainner1.tar container1
to export containers you want to keep. See export in the Docker Engine command line reference. - Uninstall the current version of Docker Desktop and install a different version (Stable or Edge), or reset your VM disk.
- Use
docker load -i images.tar
to reload previously saved images. See load in the Docker Engine. - Use
docker import -i myContainer1.tar
to create a filesystem image corresponding to the previously exported containers. Adobe flash player 11 for mac. See import in the Docker Engine.
For information on how to back up and restore data volumes, see Backup, restore, or migrate data volumes.
Where to go next
- Getting started provides an overview of Docker Desktop on Mac, basic Docker command examples, how to get help or give feedback, and links to other topics about Docker Desktop on Mac.
- Troubleshooting describes common problems, workarounds, howto run and submit diagnostics, and submit issues.
- FAQs provide answers to frequently asked questions.
- Release notes lists component updates, new features, andimprovements associated with Stable releases. For information about Edge releases, seeEdge release notes.
- Get started with Docker provides a general Docker tutorial.