Getting started with OverlayFS and Docker

Docker Engine General
1

How do I get started with OverlayFS and Docker on Ubuntu 14.04 and Docker 1.2.0?

Step by step instructions anyone?

aufs is proving a pretty bad performance wise.

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I’ve not used OverlayFS - alot of us use Btrfs tho.

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Yeah I tried brfs and perf is way better https://meta.discourse.org/t/report-on-using-discourse-docker-on-a-coreos-image/19745/4?u=sam

Wanted to compare to overlayfs (which github use with lxc)

4

I’ve created a demo boot2docker iso that has overlayfs baked in (and docker support for overlayfs).
Note that vbox shared folders does not exist in this (since I couldn’t get it to work for kernel 3.18)

http://files.container42.com/boot2docker/builds/1.3.1-dev-overlayfs/boot2docker.iso

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Have you done any benchmarking? Is it faster / slower for certain kinds of operations?

6

I found builds to be slightly slower than btrfs… but this is all on a VM, haven’t run it natively yet.
I’m told on SSD’s overlayfs should be faster than btrfs all around.
Much much faster than devmapper, of course.

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If anyone’s still interested:

  1. use linux 3.18+ kernel with overlayfs support CONFIG_OVERLAY_FS=y
  2. start >= docker-1.4.1 with -s overlay flag

Works flawlessly so far, tested on Gentoo.

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Any performance comparisons?

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I haven’t done any. There is some interesting data here Getting started with OverlayFS and Docker it’s probably worth asking these guys on any updates.

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wow, nice, we should bench what kind of difference it makes (if any)