problems in nailgun-agent because rethtool doesn't work with virtio adapters properly

(This check performed automatically)
Please, make sure that bug description contains the following sections filled in with the appropriate data related to the bug you are describing:

actual result

expected result

steps to reproduce

For more detailed information on the contents of each of the listed sections see https://wiki.openstack.org/wiki/Fuel/How_to_contribute#Here_is_how_you_file_a_bug

@Alexey, could you please provide steps to reproduce.

@Alexander, it's a floating bug. no concrete steps to reproduce.

But most often it is reproduced on the bootstrap images.

Hi Alexander, it looks like we use lspci with incorrect options.
I've updated the description of the issue.

It seems that we have 'nil' in ':bus_info' in some cases - https://github.com/openstack/fuel-nailgun-agent/blob/master/agent#L416

There is a bug in ohai, if you run this script:

-------------------------------------
require 'ohai/system'

x = 1
while 1
        os = Ohai::System.new()
        os.all_plugins

        x += 1
        puts x
end
--------------------------------------
if will fail after 100-500 iterations with

http://www.paste.org/80856

Bug exists in ohai 6.14.0-2~u14.04+mos1 and 8.4.0-1 (from latest ubuntu). There is no bug in ohai 6.14.0-2.

Colleagues, according to package ownership transferring bug to mos-linux team

The original bug (before the comment #6) was caused by the fact that rethtool doesn't work with 'virtio' interfaces. In that case it fails to execute 'ioctl' method [0] and that leads to empty value passed to lspci.
From the original log [1] it can be seen that ruby constantly tries to execute lspci with wrong (empty) parameter, and does this *before* a segfault occurs. That means that segfaul is not a root cause, and even hardly can be an issue because to reproduce it one have to run it hundreds of times. As I said, the *real* root cause here is virtio network interface that isn't supported.

If anyone think that segfault is important please file a separate bug for this.

I'm passing the bug back because in any way we can't use virtio network interfaces on slave nodes and thus this bug have no real sense.

[0] https://review.fuel-infra.org/gitweb?p=packages/trusty/rethtool.git;a=blob;f=debian/patches/0001-Added-interface-driver-and-bus_info-support.patch;h=41abd6b0b88439a29f29fad96a6ab3b2a09ffad3;hb=refs/heads/master#l61
[1] https://goo.gl/F7hJtw

Fix proposed to branch: master
Review: https://review.openstack.org/309447

There are two problems in this bug:

1. nailgun agent consumed 100% CPU.
2. lspci called with wrong arguments.

The cpu consumed not because of problems in nailgun-agent, because if you look at the times of log messages in nailgun-agent.log you will find that it was called not more that several time per minute. So I hope this problem will be fixed in scope of https://bugs.launchpad.net/fuel/+bug/1572485 by https://review.fuel-infra.org/#/c/20149/

2. This problem will be fixed by https://review.openstack.org/#/c/309447/

ETA: 06.06.2016

Wasn't able to reproduce it on 9.0-mos #488.

CPU is OK, as well as lspci invocation, so closing...

[root@nailgun ~]# shotgun2 short-report | head -n8
cat /etc/fuel_build_id:
 488
cat /etc/fuel_build_number:
 488
cat /etc/fuel_release:
 9.0
cat /etc/fuel_openstack_version:
 mitaka-9.0