I am experimenting docker and I plan to dockerize my project's CI infratsructure. I am building dockerfiles on 3 different machines: Fedora, Ubuntu, and Boot2Docker (a virtiual machine under windows).
Docker builds on fedora are a lot slower than on the other 2 machines, especially the opration that creates a new image after a Step in the Dockerfile.
So my question is: Is device mapper a lot slower than AUFS or should I search for some other reason ? Should I expect better if I put in place a RHEL7 config ?
Config1: fedora 21 (3.18.3-201.fc21.x86_64)
sudo docker info
Containers: 27
Images: 1353
Storage Driver: devicemapper
Pool Blocksize: 65.54 kB
Backing Filesystem: extfs
Data Space Used: 82.77 GB
Data Space Total: 107.4 GB
Metadata Space Used: 103.9 MB
Metadata Space Total: 2.147 GB
Udev Sync Supported: true
Library Version: 1.02.93 (2015-01-30)
Execution Driver: native-0.2
Kernel Version: 3.18.3-201.fc21.x86_64
Operating System: Fedora 21 (Twenty One)
CPUs: 8
Total Memory: 31.38 GiB
Config2: Ubuntu 14.04.2 LTS
Containers: 89
Images: 589
Storage Driver: aufs
Backing Filesystem: extfs
Dirperm1 Supported: false
Execution Driver: native-0.2
Kernel Version: 3.13.0-49-generic
Operating System: Ubuntu 14.04.2 LTS
CPUs: 8
Total Memory: 31.38 GiB
Config3: Boot2Docker (virtual linux machine running under Windows. docker default solution for Windows)
docker info
Containers: 14
Images: 215
Storage Driver: aufs
Backing Filesystem: extfs
Dirperm1 Supported: true
Execution Driver: native-0.2
Kernel Version: 3.18.11-tinycore64
Operating System: Boot2Docker 1.6.0 (TCL 5.4); master : a270c71 - Thu Apr
CPUs: 8
Total Memory: 1.961 GiB
I read this article but it still did not help me to clear things out.
Device Mapper's "slowness" has been documented, especially when used with a loop device.
Here's a useful presentation I found: http://jpetazzo.github.io/assets/2015-03-03-not-so-deep-dive-into-docker-storage-drivers.html.
I would look into overlay.