12:20 a.m.
On 01/30/2014 07:41 AM, Kashyap Chamarthy wrote:
Last night I was tinkering with `systemd-nspawn` -- namespace based
container for testing, I thought I'll post what I tried with libguestfs
here:
Prerequisite
------------
Because of an audit subsystem incompatibility bug - rhbz#966807[1], turn
off auditing by booting the host w/ 'audit=0' on Kernel command line.
(NOTE: There's work in progress[2] in upstream Kernel to fix this.)
Create container
----------------
On the host, specify an installroot (/srv) and install a minimal Fedora
20 distribution:
$ yum -y --releasever=20 --nogpg \
--installroot=/srv/testcontainer \
--disablerepo='*' --enablerepo=fedora \
install systemd passwd yum \
fedora-release vim-minimal
Boot into the container, set a password:
$ systemd-nspawn -D /srv/testcontainer
[. . .]
-bash-4.2# passwd
Start the container w/ systemd:
$ systemd-nspawn -bD /srv/testcontainer
[. . .]
-bash-4.2#
Building Libguestfs
-------------------
Inside the minimal Fedora 20 container, install libguestfs dependencies,
clone the libguestfs git repository:
-bash-4.2# yum-builddep libguestfs -y
-bash-4.2# git clone git://github.com/libguestfs/libguestfs.git
Build and test libguestfs in the container:
-bash-4.2# cd libguestfs
-bash-4.2# ./autogen.sh && time make 2>&1 \
| tee /tmp/libguestfs-compile.log
-bash-4.2# time make -k check \
LIBGUESTFS_DEBUG=1 LIBGUESTFS_TRACE=1 2>&1 \
| tee /tmp/libguestfs-test.log
Notes
-----
- If you need to build a container without networking (once all the
relevant dependencies are cloned/and network related operations
are done), the container can be invoked with no network
devices (except loopback):
$ systemd-nspawn -bD /srv/testcontainer --private-network
[. . .]
-bash-4.2#
- Single `make` job timing to compile everything:
real 31m9.792s
user 17m18.359s
sys 13m17.868s
For comparison, on the _host_, the same single `make` job timing:
real 13m41.440s
user 13m5.816s
sys 1m9.911s
- `make -k check` is still running as I write this, albeit
a bit slow.
This just finished (in the container):
[. . .]
grep -v -E '^(examples|gnulib|perl/(blib|examples)|po-docs|tests)/' | \
grep -v -E '/((guestfs|rc)_protocol\.c)$' | \
LC_ALL=C sort > po/POTFILES
cd .; \
find builder mllib resize sparsify sysprep -name '*.ml' | \
LC_ALL=C sort > po/POTFILES-ml
make[1]: Leaving directory `/root/libguestfs'
make: *** [check-recursive] Error 1
GEN public-submodule-commit
make: Target `check' not remade because of errors.
real 474m53.630s
user 325m54.254s
sys 205m58.032s
-bash-4.2# git log | head -1
commit c841d08d7084db69e81614d54423686cf0566ad6
Again, for comparison, `make -k check` on _host_:
real 63m1.078s
user 54m39.393s
sys 12m8.130s
I think it's worth noting that this is all with Btrfs on the host. And,
the systemd[*] wiki page indeed warns: "YMMV if you use LVM or btrfs."
It needs to be examined what the result would be if I repeat this on
ext4 (and SSD).
[*] http://www.freedesktop.org/wiki/Software/systemd/VirtualizedTesting/
--
/kashyap