`docker build` hangs, com.docker.hyperkit using ~200% CPU

Expected behavior

docker build works normally

Actual behavior

docker build hangs on a seemingly innocuous step, then com.docker.hyperkit starts using max CPU. Even after killing the build, com.docker.hyperkit continues to eat CPU cycles.


Diagnostic ID 4F8D08FD-BED4-43E5-9FEB-4BA26C287886

Docker for Mac: version: mac-v1.12.0-beta16.2
OS X: version 10.11.5 (build: 15F34)
logs: /tmp/20160620-171832.tar.gz
failure: No error was detected
[OK] docker-cli
[OK] app
[OK] menubar
[OK] virtualization
[OK] system
[OK] osxfs
[OK] db
[OK] slirp
[OK] moby-console
[OK] logs
[OK] vmnetd
[OK] env
[OK] moby
[OK] driver.amd64-linux


Same issue here. What does your step do? I have the same behavior while executing “run” step with “webpack” TypeScript to JavaScript code compiling.

Me (and several colleagues) experience the same issue. During docker build, the process sometimes hangs and com.docker.hyperkit occupies 200% CPU for several minutes untill it recovers and the process continues. I created a pastebin with a process sample of a hanging process: http://pastebin.com/bpcDfu6s