CoreDev

Revision 1 as of 2016-08-31 14:00:46

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I, Christian Ehrhardt, hereby apply for core-dev to enhance my ability to drive tasks for the server team and Ubuntu in general

Name

Christian Ehrhardt

Launchpad Page

paelzer

Wiki Page

n/a

Who I am

I'm member of Canonical in the Server Team since late 2015 and working there primarily on virtualization and automation related things like DPDK packaging and testing, Cloud-init/Curtin development, qemu/libvirt bug handling and effectively bug handling of any server related issues as well. I have a long history in System z regarding Linux Performance Analysis and due to that also work on s390x related issues every now and then. Also I work a lot on merging new versions of server related packages and cleaning out bugs in them.

My Ubuntu story

My Linux story starts with Gentoo around 2003. It suited my nature of optimizing things and emerge was a great package management tool at the time. Since around 2008 I changed all my systems to Ubuntu as it was just easier to consume in so many ways. Over time the full range from small embedded or HTPC to reasonable Server installations as well as on many of my Desktops were based on Ubuntu. I was closer to the Kernel for a while with a Thesis about I/O Schedulers in 2004. Then I worked with Linux as a performance analyst in IBM since 2004, but that was focused on System z where for a long time only Suse and RedHat existed. Yet that brought me into contact with so many benchmark, packages and the Kernel. A typical jack of all trades - expert in none but skilled in everything approach - causing a few fixes here and there around the open source community. I was switching between Performance analyst and a KVM Developer Role in between to further bolster my set of experiences. When the chance to join Canonical showed up in 2015 I saw the opportunity to combine my IBM Linux history with really working on free software.

My involvement

Examples of my work / Things I'm proud of

- Optimizing KVM on s390x to outperform the classic z/VM Hipervisor in various areas up to 5x - full range from tuning to kernel patches. - Identifying several complex performance issues over the years from faulty chip design up to sub-optimal cross application interactions. - recently making DPDK available on Ubuntu in (IMHO) the first user consumable way (https://insights.ubuntu.com/2016/05/05/the-new-simplicity-to-consume-dpdk/) - founding and driving joint packaging group to continue evolving DPDK in a colaborating way for Debian and Ubuntu (https://wiki.fd.io/view/Deb_dpdk)

Areas of work

Since joining Canonical I was part of the Server Team and are:

  • working on Curtin with Scott Moser
  • working on Subiquity with Ryan Harper
  • working on various s390x issues with Dann Frazier and Dimitri Ledkov
  • taking over DPDK completely from Stefan Bader
  • working on openvswitch-dpdk with James Page
  • working on various merges/fixes with James Page, Chris Arges, Martin Pitt, Adam Conrad, Robie Basak

The DPDK package is sometimes feeling a bit bleeding edge. Most pieces that are not regularly tested tend to break on the first try. That defined the need for regular uploads, participation in the upstream projects and so on. Bugs so far show up primarily due to my effort to implement a CI testing infrastructure for it, but it is expected to get more once it is in 16.04 and due to our pushes in OPNFV. So I clearly expect me driving more uploads - I'll always want some review by fellow coworkers which we do for each other anyway, but to be less dependent on the actual uploads it would certainly increase efficiency - which is why I'm applying for these core-dev permissions.

Things I could do better

There are still a lot of hidden "this is the way it is done in Ubuntu" gems that I have to uncover and adapt. But it gets better with every bug/upload/discussion I work on. I got the feeling recently that the last bunch of merges went by far smoother and easier. Other than that I really want to be even more active in "helping people" - I started to keep an eye on IRC channels and askubuntu for that and it feels good - I just think that makes Ubuntu better overall.

Plans for the future

General

IMHO Linux in general has a very bad swapping spike behavior when passing into memory shortage that I really hate. I have quite some ideas about a triple watermark design and low prio async writers and all that stuff that I want to work on one day. That is a long term thing I still carry from my performance times and I don't know if I can ever tackle this - but it is one particular thing in the back of my mind.

Also more recently DPDK needs a new way to work-everywhere-but-optimize-for-local-system. That is just a meta-level or two above "-march X -O3". I'm driving a few discussions about various ways to do so - hope that will work some way. That clearly is something that I'd like to see improved.

What I like least in Ubuntu

I was a bit shocked when I saw the huge amount of open bugs. No offense to anybody, it is just more than anyone can handle. And to a huge part it can be covered with triaging and prioritization alone, but sometimes I just think there should be more effort on that. When I had the time to focus on a particular package I found that most of the time 80% of the bugs never/no-more apply and could be closed - maybe all of Canonical should do that for a week one day. For myself I hope that I can continue to have the opportunity to work on more packages to get an even broader feeling and set of experience of the Linux world. That way I can do my part to reduce the amount of open issues.

Probably somewhat related to my feelings about open bugs, I also think we should make more use of the adt infrastructure. So many packages have no or outdated dep8 tests - i'd really like to see some effort to improve these.

I guess I can't deny my QA related performance Analyst history Smile :-)


Comments

If you'd like to comment, but are not the applicant or a sponsor, do it here. Don't forget to sign with @SIG@.


Endorsements

James Page

General feedback

I've worked extensively with Christian over the last 6 months on the integration of DPDK with Open vSwitch, sponsoring his changes to the DPDK package into the archive.

He demonstrates a highly professional attitude to the maintenance of DPDK, participating actively in the upstream DPDK community and taking strong ownership of both the packaging and testing of DPDK in Ubuntu.

I'd trust him with upload rights for the dpdk package in Ubuntu.

Specific Experiences of working together

Lots of DPDK uploads; I did the counterpart changes into Open vSwitch (some of them provided by Christian):

http://ubuntu-dev.alioth.debian.org/cgi-bin/ubuntu-sponsorships.cgi?render=html&sponsor=james+page&sponsor_search=name&sponsoree=christian*&sponsoree_search=name

Areas of Improvement

I'd like to see Christian diversify the packages he's helping with across Ubuntu; I think he will be a valuable asset in the Ubuntu Community in terms of his own work and his ability to support other developers. I'd like to see him participate in the patch pilot programme ASAP!

Chris J Arges

General Feedback

I've reviewed and sponsored some of Christian's work on DPDK. He's shown attention to detail, great communication, and quick understanding of Debian packaging and Ubuntu processes. I believe that he will be able to effectively handle uploading DPDK without issue.

Specific Experiences of working together

https://ubuntu-dev.alioth.debian.org/cgi-bin/ubuntu-sponsorships.cgi?render=html&sponsor=chris+j+arges&sponsor_search=name&sponsoree=christian*&sponsoree_search=name

In addition I've reviewed some of his SRU's in the queue and those have also been of good quality.

Areas of Improvement

I think Christian can handle more than just DPDK and should work towards being able to upload into more server packages.

-- arges 2016-06-06 12:57:30

As a sponsor, just copy the template below, fill it out and add it to this section.


Scott Moser

General feedback

I do not think I've sponsored any of Christian's package changes, but he has worked with me on cloud-init and curtin. I also have some experience with his DPDK work. In all cases, the thing that stands out in Christian's work is the effort he puts into testing. He strives to have good code coverage and is careful and considerate in all his work.

Specific Experiences of working together

Christian has worked on cloud-init and curtin through merge proposals at:

Areas of Improvement

Christian has less specific packaging experience than core developer or someone with broader archive access. I do not see that as a real problem due to his willingess to ask questions, and to be careful.


TEMPLATE

== <SPONSORS NAME> ==
=== General feedback ===
## Please fill us in on your shared experience. (How many packages did you sponsor? How would you judge the quality? How would you describe the improvements? Do you trust the applicant?)

=== Specific Experiences of working together ===
''Please add good examples of your work together, but also cases that could have handled better.''
## Full list of sponsored packages can be generated here:
## http://ubuntu-dev.alioth.debian.org/cgi-bin/ubuntu-sponsorships.cgi?
=== Areas of Improvement ===


CategoryPerPackageUploaderApplication