Exoscale, a Swiss Cloud Provider with CloudStack

Over the last couple weeks I have been using exoscale, a swiss public cloud provider based on CloudStack. They just launched after a beta testing phase that I had the chance to be part of. Their offering is primarily aimed at developers. The folks at Exoscale were kind enough to give me couple "gift cards" during the CloudStack Geneva meetup and I was able to get going. Together with PCExtreme, Leaseweb, and iKoula they are one more European public cloud provider in production with Apache CloudStack that I know of.

Their cloud is almost straightforward: two data centers in Geneva and Vernier, with hardware hosted by Equinix. They run Apache CloudStack 4.0.2, the latest release and use KVM hypervisors on Ubuntu based servers. One customization that they made and that I am aware of is that they patched CloudStack to output logs using logstash and use Kibana for visuzalization. They offer CentOS 6.4 and Ubuntu 12.04/13.04 64 bit templates with instance types from 512MB with 1 core to 32 GB with 8 cores. Their development and operations team is relatively small for such an offering but they are backed by the Veltigroup a leading IT provider in Switzerland, which gives them a 20 person team for support. Their developers are seasoned IT infrastructure enthusiasts who participate in the DevOps, openBSD, Clojure and Pallet community. The lead developer, Pierre-Yves Ritschard, formerly with paper.li, recently participated in DevOps Days Paris and has contributed a Clojure client to CloudStack: clostack. They are embracing open source, not only by using it, but also by contributing to the various communities that make up the foundation of Cloud services.

While CloudStack comes with a powerful and efficient Web UI, exoscale decided to create their own UI and integrate it with a ticketing, monitoring and billing system that they developed. It reinforces the fact the CloudStack API is extremely rich and that the default UI was actually designed as a proof of concept rather than something that all users should use. The UI will please developers by its simplicity and straigthforward ease of use. From talking to them, I know they they will soon open source the python client they developed to build the UI backend. Pierre Yves told me it resembled a little bit my toy UI that uses Flask and builds a REST wrapper on top of the CloudStack API. See a snapshot of an instance view below:

They envision an entirely public cloud, meaning that all their instances are on the public network (nb: They also have a premium service for the enterprise with secure VPN access). They use a CloudStack basic zone with security groups ala EC2. Users can get VNC access and of course ssh access to the instance using ssh keys created via the console. Since it is still in beta-testing they have currently turned off some of the features like snapshotting. These feature limitations are well documented and in their roadmap for future releases of their Cloud services. In the meantime they are also working on high level services like Jenkins continuous infrastructure services and most probably big data services. The Big Data service is just a guess on my part but would make sense considering Pierre-Yes involvement with Pallet and a recent demo he did at Eurocloud.

I have used exoscale a lot in those last two weeks and I am extremely pleased with it. It is actually becoming my favorite testbed. The UI is great as I mentioned, but all the CloudStack clients also work (of course :) ), CloudMonkey is easily setup to talk to their endpoint, I submitted patches to libcloud last week and you can now use with exoscale. I even contributed a CloudStack driver for SaltStack (an alternative to Chef and Puppet) based on testing with exoscale. Right away I felt comfortable with exoscale and even gave a lecture at HEPIA where I put 7 students on it in 20 minutes. If you want to learn more, Exoscale will be at Build a Cloud Day Paris on June 19th.

So here is the catchphrase of the blog: Exoscale, it's simple and it works

Update on Apache CloudStack Community Analysis

Since my last post on the analysis of the CloudStack community, we have graduated and became a top-level project. It's about time to give an update on what can be seen as a metric of the health of our community.

All the data presented is based on the analysis of the mailing lists, the data is publicly accessible, I have used it previously, just when we graduated March 22nd, in January and back in November when I did some social network analysis. This study was inspired by John Jiang, now working at Eucalyptus, you can read his analysis, note that he moved it to the Eucalyptus website.

Methodology: As explained in previous posts, a Contributor is considered as someone who sent an email to one of the CloudStack mailing lists. This is not to be confused with a Committer which at the ASF is meant to represent someone with write access to the code. Not all code contributors have write access. I identify Companies as the email domain used by the Contributors. This is because Contributors are none-affiliated in the ASF. Obviously it has some limitations as email domains such as gmail.com can represent different companies. All emails are loaded in a mongodb database and queries are performed to extract the plots that you will see below. We currently have seven mailing lists of varying traffic: announce, users, users-cn, dev, marketing, commits, issues. Note that all JIRA emails are now sent to the issues list. Subscription to these lists and number of messages last month is as follows:

* dev@ 609 subs / ~2600 msgs in Apr
* users@ 782 subs / ~800 msgs in Apr
* issues@ 109 subs / ~2400 msgs in Apr
* commits@ 166 subs / ~3300 msgs in Apr
* marketing@ 85 subs / ~260 msg in Apr
* users-cn@ ~300 subs / ~260 msgs in Apr

Contributors: The plots below show the number of contributors per month since we became an ASF project as well as an accumulation to date. Comparison with traffic prior to joining ASF can be seen in the previous posts. The number of monthly contributors in dev is reaching 225 , while the number of monthly contributors in users is reaching 175. Most notable is that the number of contributors in the users list seem to be closing on the number of contributors in dev. It may indicate a stabilization of the number of developers and an increase in the user base. The accumulation on both lists is now over 500. A comparison of both contributor sets gives us an estimate of 806 for the entire CloudStack community. Of course this does not include people who may only participate in the marketing or announce list, but they are much lower traffic lists. It also does not include participants in the Chinese user lists. This will be in the next post hopefully. From the subscription data listed above you can also see that we have roughly a 30% activity ratio, meaning that 1/3 of the subscribers actually send emails to the lists. Difficult to know if this is a good or bad number, one would need to compare with other ASF projects.

Companies: The plots below show the number of companies contributing on the dev and users lists as well as an accumulation to date. Similarly to the monthly contributor count we are seeing a faster diversification on the users list. This shows that the users list is adding more companies faster than the dev list (~80 and ~60 per month respectively). The accumulation has reached ~230 on the users list and ~190 on the dev list, for a combined 319 total.

Commits and Marketing: The commits list represents the number of committers than modify the code. These committers often apply patches submitted by other contributors without write access to the code. Therefore the plots should not be seen as the total number of code contributors. The plot below shows an increase in the number of Committers just shy of 40. The marketing list is a new list that deals with event planning, its trend is not yet established but the data shows between 50 and 30 contributors per month.

Social Networks: The following graphs shows social networks of the dev and users list. They are aimed at identifying who is most central to the community. It can be used to identify great contributors that should be recognized and be invited to become an Apache committer. Ultimately I want to use it to build a topic based network, so that people searching for a particular subject know who to talk to. I plan to build an interface that would use keywords to dynamically build these graphs and identify the people who contribute to that topic the most. The graphs show the networks for the last four months. Our new Apache CloudStack vice-president Chip Childers is clearly the most central node in the dev list and Ahmad Emneina is the most central contributor on the users list. The size of the nodes is proportional to their centrality and the thickness of the edges shows the strength of the connection between two nodes. Several nodes (contributors) have been filtered to render a readable picture.

Finally, it is important to note that some contributors are not active on the mailing lists. Even though this is an ASF mantra. Specifically we have engaged in a very active translation effort to bring CloudStack to all countries worldwide. Our translation team has 32 members as off the last count. All translation is handled via transifex. I am also working on git analysis to show better information on commits and I pointed out to John Jiang that he used the wrong repository in his latest study. Stay tuned.

Quantifying the Apache CloudStack Community

CloudStack is now an Apache Top Level Project (TLP) at the Apache Software Foundation (ASF), the announcement just came out. What the incubation period has meant for CloudStack has nothing to do with code maturity. CloudStack was mature and used in enterprise settings before it entered incubation at the ASF. What incubation meant was that CloudStack evolved into an open source community, self-governed by the Apache Way: transparency, meritocracy, respect, non-affiliation and consensus in no particular order. The community has learned and demonstrated that it understands the principles and processes laid by the Apache Software Foundation and that it can now operate more autonomously.

Growing an open source community is challenging, folks who participate come from various backgrounds, may seldom meet and interact mostly via emails, social media, instant messaging. Participants come from all over the world, work in different time-zones and donate their time after (and sometime while) dealing with day jobs and family. Participants rally around a project that they deem interesting, sometime just to land a hand for a few months, or sometimes because their day job requires them to do it. In that very heterogeneous and fluctuating mix, an open source software community emerges, self-governed, sustainable and non-affiliated. In the last 12 months CloudStack has done just that, building a community from the ground up, developing and understanding the principles laid out in our bylaws, adapting -if need be- people's way of developing software, getting to know each other, welcoming new members every day and setting the foundation for a sustainable software.

When growing a community it is fairly natural to want to measure how well we are doing and how healthy the community is. Over the last several months I have started collecting some data to analyze our community, trying to see how we were doing and interacting. I mostly looked at our public mailing lists doing a study similar to the one done about comparing CloudStack, OpenNebula, OpenStack and Ecualyptus. Secretly, this was also a good way for me to sharpen a few skills on BigData, not that big actually but I used MongoDB instead of MySQL so that qualifies as BigData :). Defining membership in an open source community is a challenge since there is no concept of membership, even the concept of contribution is ill-defined. What constitutes a contribution ? Which channels need to be considered ? In the case of ASF for instance, contribution to code may only mean being a committer, but a committer is someone with write access to the code. Just counting committers will leave out all the folks sending patches, doing testing, doing user support, translating documentation, giving talks and so on. Also while at the ASF everything happens on the mailing list, what about IRC channels, social media like Facebook, Twitter and Linkedin, and what about other communities that may arise around a particular software: sub-projects, user groups etc. In this analysis I decided to only look at our public mailing lists but there is more to it than just this data source.

The two figures below show the number of individual contributors measured by unique email addresses used to send messages to the users and developers mailing lists. The red lines represent data from the users and developers mailing list prior to entering incubation at the ASF. The blue lines represent the ASF specific lists. Significant is the impact that the move to the ASF has had on the number of contributors. The developers list has peaked over 200 per month and the users list has peaked over 150 per month so far (figure on the right). The last data point is March (as of March 21st) and numbers will go up by the end of the month. The graph on the right shows the accumulation of contributors, adding all unique email addresses every month into a set. This shows us again that the move to ASF has had a huge impact on the growth rate of the community and that both list grow at relatively the same pace. Adding the accumulated number of contributors to both list and removing duplicates present in both sets, this gives us a magic number of 722 CloudStack contributors to date.

As mentioned earlier these numbers of contributors are different from the number of Apache CloudStack committers. According to our bylaws contributors can become committers and gain write access to the code when invited by the Project Management Committee (PMC). Just today we welcomed three new committers for a current total of 54. This number is again relative in terms of contribution to code, since committers apply patches from contributor who are not yet committers (I know confusing :) ). A quick look at our git repo, shows a current total of 159 code contributors. To that we could also add the 32 contributors who helped with the translation via transifex which may or may not have participated in the mailing lists.

These numbers show a growing community sparked by the move to the ASF. While at the start of incubation the initial set of committers and contributors where only from Citrix who donated the code, we are also seeing a diversification in the number of companies involved. Talking about affiliation is actually a cardinal sin of the Apache Way. At the ASF only individuals matter, but it is fair to say that for CloudStack to be successful we need to see adoption/participation by a diverse set of companies. The two figures below show just that with the number of companies identified by the email domain used by the contributors. This is not perfect since contributors often do not use their work email but gives a good idea of the trend. Similarly to the plots about contributors we plot the number of companies (really email domains). Clearly the growth in the number of companies involved has increased since joining the ASF, we currently see around 50 companies involved in CloudStack every month. Accumulating all these companies we reach almost 200 on both lists. Removing duplicates from both sets we estimate the total number of companies to 272. Even if some of those companies are only represented by a single individual this is still a very strong number that shows great diversification. Interestingly over the last three months we see that the participation in the user list has shown more diversity than on the developer list.

Finally, looking at the cloudstack-commits mailing list we try to identify the number of committers to the code. The figure below shows the number of committers and the number of commits measured by number of emails and unique email addresses used on the commits mailing list. We already mentioned that we had 54 committers but that some of those committers gained their rights based on contribution which could be as diverse as development, user support, translation etc. Therefore it is no surprise to see the number of committers peaking at 35 and the accumulated number reaching 45. The number of commits is growing, reaching 1500 a month during the 4.0 release, easing up during christmas time and peaking again over 2500 per month prior to code freeze of the 4.1 release.

All in all, analyzing lots of emails showed me that moving to ASF has had a tremendous impact on CloudStack, with over 700 contributors, close to 60 committers, 30 translators, over 1 million lines of code, CloudStack is self-governed and here to stay.