* Increase Moby fs.file-max to 524288
* Use Mac System Configuration database to detect DNS
* HyperKit updated with dtrace support and lock fixes
* Fix Moby Diagnostics and Update Kernel
* UI Fixes
* osxfs: fix socket chowns
**Known issues**
* Docker.app sometimes uses 200% CPU after macOS wakes up from sleep mode. The issue is being investigated. The workaround is to restart Docker.app
* There are a number of issues with the performance of directories bind-mounted with `osxfs`. In particular, writes of small blocks and traversals of large directories are currently slow. Additionally, containers that perform large numbers of directory operations, such as repeated scans of large directory trees, may suffer from poor performance. More information is available in [Known Issues](/manuals/desktop/troubleshoot-and-support/troubleshoot/known-issues.md).
* Under some unhandled error conditions, `inotify` event delivery can fail and become permanently disabled. The workaround is to restart Docker.app
### Beta 21.1 Release Notes (2016-08-03 1.12.0-beta21.1)
This bug fix release contains osxfs improvements. The fixed issues may have
been seen as failures with apt-get and npm in containers, missed `inotify`
events or unexpected unmounts.
**Hotfixes**
* osxfs: fixed an issue causing access to children of renamed directories to fail (symptoms: npm failures, apt-get failures)
* osxfs: fixed an issue causing some ATTRIB and CREATE `inotify` events to fail delivery and other `inotify` events to stop
* osxfs: fixed an issue causing all `inotify` events to stop when an ancestor directory of a mounted directory was mounted
* osxfs: fixed an issue causing volumes mounted under other mounts to spontaneously unmount (docker/docker#24503)
### Docker for Mac 1.12.0 (2016-07-28 1.12.0-beta21)
**New**
* Docker for Mac is now available from 2 channels: **stable** and **beta**. New features and bug fixes will go out first in auto-updates to users in the beta channel. Updates to the stable channel are much less frequent and happen in sync with major and minor releases of the Docker Engine. Only features that are well-tested and ready for production are added to the stable channel releases. For downloads of both and more information, see the [installation guide](/manuals/desktop/setup/install/mac-install.md).
**Upgrades**
* Docker 1.12.0 with experimental features
* Docker Machine 0.8.0
* Docker Compose 1.8.0
**Bug fixes and minor changes**
* Check for updates, auto-update and diagnose can be run by non-admin users
* osxfs: fixed an issue causing occasional incorrect short reads
* osxfs: fixed an issue causing occasional EIO errors
* osxfs: fixed an issue causing `inotify` creation events to fail
* osxfs: increased the `fs.inotify.max_user_watches` limit in Moby to 524288
* The UI shows documentation link for sharing volumes
* Clearer error message when running with outdated VirtualBox version
* Added link to sources for qemu-img
**Known issues**
* Docker.app sometimes uses 200% CPU after macOS wakes up from sleep mode. The issue is being investigated. The workaround is to restart Docker.app
* There are a number of issues with the performance of directories bind-mounted with `osxfs`. In particular, writes of small blocks, and traversals of large directories are currently slow. Additionally, containers that perform large numbers of directory operations, such as repeated scans of large directory trees, may suffer from poor performance. For more information and workarounds, see [Known Issues](/manuals/desktop/troubleshoot-and-support/troubleshoot/known-issues.md) in [Logs and Troubleshooting](/manuals/desktop/troubleshoot-and-support/troubleshoot/_index.md).
* Under some unhandled error conditions, `inotify` event delivery can fail and become permanently disabled. The workaround is to restart Docker.app
### Beta 20 Release Notes (2016-07-19 1.12.0-rc4-beta20)
**Bug fixes and minor changes**
* Fixed `docker.sock` permission issues
* Don't check for update when the settings panel opens