8712ac1fdf
Use /var/lib/fuel/ibp as the image build directory. This directory
will be backed by a volume in the mcollective container which reduces
IO overhead and makes image build time reasonable.
fuel_agent (which builds Ubuntu images) runs in the mcollective
container. A container filesystem is backed by dm-snapshot which
is known to have a poor write performance, especially for large
files (like OS images). By default docker storage is a loopback file
residing in /var/lib/docker. Thus the data written to the OS image
being built goes through a number of layers:
ext4 -> loop -> dm-snapshot (/var/lib/docker-> loop ->
-> ext4 (/var/lib/docker) -> dm-linear (os-varlibdocker) ->
-> hard drive
If the master node runs on a VM rather than a physcial hardware
the above chain gets even more complicated:
ext4 -> loop -> dm-snapshot (/var/lib/docker-> loop ->
-> ext4 (/var/lib/docker) -> dm-linear (os-varlibdocker) ->
-> virtual hard drive (qemu) -> qcow2 -> ext4 (host)
Using the volume makes it possible to eliminate the extra layers,
so the written data goes through
ext4 -> loop -> ext4 -> dm-linear (os-var) -> hard drive
Note: this patch can be merged before the ones which actually make
/var/lib/fuel/ibp a host volume (obviously there won't be any
performance gain until fuel-library/fuel-main bits get merged).
Merge-After: https://review.openstack.org/201947
Related-Bug: #1457643
Change-Id: Ic4d258523aa13b3879a730edb2d910522ec24c93
|
||
|---|---|---|
| fuel_upgrade | ||
| MANIFEST.in | ||
| requirements.txt | ||
| setup.py | ||
| test-requirements.txt | ||
| tox.ini | ||