Canonical Voices

Colin Ian King

Forcing out bugs with stress-ng

stress-ng logo
Over the past few months I've been adding several new stress tests and a lot more stressor options to stress-ng for Ubuntu 16.04 Xenial Xerus.  I try to track new system calls and features landing in the kernel and where appropriate add a stress test to try and force out bugs.

Stress-ng has found various kernel bugs, such as CVE-2015-1333 and LP:#1526811 as well as bugs in user space (for example, daemons crashing) when memory pressure is very high.  Simple abusive tricks, such as aggressively trying to allocate every free page in memory are useful in finding drivers that don't necessary check for memory allocation failures.  For example, today I was caught out when a USB ethernet dongle driver didn't check for a null pointer due to an allocation failure and stress-ng ended up triggering a kernel oops (fortunately, this bug was fixed in a recent kernel).

The underlying philosophy for stress-ng is "use and abuse standard Linux interfaces and see how far we can push them to destruction".  I'm pretty sure there are plenty of creative folk out there who can dream up dastardly ways to make stress-ng even more stressy, so contributions are always warmly accepted!  I have a mirrorred copy of the git repository on github to make it easy for developers to get their hands on the code.

We've been using stress-ng on ARM based SoC kernels to force out bugs and this has been useful in finding areas where non-swap based systems break. You really don't want your kernel oopsing or processes segfaulting when a IoT device has run low on memory.

My original intent for stress-ng was just to make a system run hot and force thermal overruns. However, I soon discovered it is useful to force kernel bugs out by attempting to (pathologically) thrash most of the system calls.  I've also added perf stats to stress-ng to track performance of standard stress scenarios over kernel versions to get an early warning of any potential performance regressions.  So stress-ng is a bit of a mixed bag of stress tests and performance measuring goodness.

When I get some free time I hope to run stress-ng against a GCOV instrumented kernel at see how much test coverage I get on a kernel. I suspect there are a lot of core kernel functionality still not being touched by stress-ng.

I've also tried to make stress-ng portable, so it can build fine on GNU/Hurd and Debian kFreeBSD (with Linux specific tests not built-in of course). It also contains some architecture specific features, such as handling the data and instruction cache as well as the x86 rdrand instruction and cache line locking. If there are any ARM specific features than can be stressed I'd like to know and perhaps implement stressors for them.

Anyhow, I believe stress-ng is almost feature complete for Ubuntu Xenial, however, I expect it to grow in features over time since there is always new functionality landing in the Linux kernel that needs to be thrashed tested.

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Dustin Kirkland

As always, I enjoyed speaking at the SCALE14x event, especially at the new location in Pasadena, California!

What if you could adapt a package from a newer version of Ubuntu, onto your stable LTS desktop/server?

Or, as a developer, what if you could provide your latest releases to your users running an older LTS version of Ubuntu?

Introducing adapt!

adapt is a lot like apt...  It’s a simple command that installs packages.

But it “adapts” a requested version to run on your current system.

It's a simple command that installs any package from any release of Ubuntu into any version of Ubuntu.

How does adapt work?

Simple… Containers!

More specifically, LXD system containers.

Why containers?

Containers can run anywhere, physical, virtual, desktops, servers, and any CPU architecture.

And containers are light and fast!  Zero latency and no virtualization overhead.

Most importantly, system containers are perfect copies of the released distribution, the operating system itself.

And all of that continuous integration testing we do perform on every single Ubuntu release?

We leverage that!
You can download a PDF of the slides for my talk here, or flip through them here:

I hope you enjoy some of the magic that LXD is making possible ;-)


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Alejandra Obregon

Designing cloud tools in Cape Town

Our cloud design team has just returned from a trip to Cape Town for our mid-cycle sprint. We have the luxury of being collocated in London and working closely throughout the whole year, but these sprints give us an invaluable opportunity to collaborate with other stakeholders and engineers working around the world. We get together to define priorities and review progress on our goals for this cycle.

We can showcase upcoming features and designs and get feedback from a variety of sources.

This time we also heard from cloud architects who are building data centres with the products we design. It gave us an insight into how our products are being received in the field – what is working well in reality, what we need to do more of.

The week mainly involves lots of talking, drawing, presenting and discussing topics and we work to a tight schedule.

But we also get a chance to socialise and get to know people we work with in different time zones, which I think is just as valuable as the working bit.

At the end of the week we plan in detail for the next few weeks based on the outcomes of our conversations.

It’s an exciting time to be at Canonical. A new version of our provisioning product MAAS has just been released and it’s a huge evolution and something we’re very proud of.

The new Juju GUI just went live today! It has a completely revamped interface to make it easier to build and manage your cloud applications and services.

Our Autopilot tool for building OpenStack clouds will have a really nice set of new options in our next release.

Below are some photos of our week in Cape Town. I’m looking forward to our next Ubuntu release in April and the evolution of the cloud tools that come with it.

If you’d like to join the fun, get in touch, we’re hiring!


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Colin Watson

If you are a member of Launchpad’s beta testers team, you can now try out Git-based recipes.  These work very similarly to the Bazaar-based recipes that Launchpad has supported for a long time, with a few minor changes to handle differences in the underlying version control system: the main thing you’ll probably notice is that you almost always need to explicitly specify a branch name.  The recipes documentation explains what to do; if you’re already familiar with how recipes work for Bazaar, then you should probably skip straight to the recipes guide to look over the differences for Git.

Please try this out and report any bugs you find.  If all goes well, we’ll open this up to all users in a couple of weeks.

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This week from Tuesday to Thursday four Canonical Foundations team members held a virtual sprint about the proposed-migration infrastructure. It’s been a loooong three days and nightshifts, but it was absolutely worth it. Thanks to Brian, Barry, and Robert for your great work!

I started the sprint on Tuesday with a presentation (slides) about the design and some details about the involved components, and showed how to deploy the whole thing locally in juju-local. I also prepared a handful of bite-size improvements which were good finger-exercises for getting familiar with the infrastructure and testing changes. I’m happy to report that all of those got implemented and are running in production!

The big piece of work which we all collaborated on was providing a web-based test retry for all Ubuntu developers. Right now this is limited to a handful of Canonical employees, but we want Ubuntu developers to be able to retry autopkgtest regressions (which stop their package from landing in Ubuntu) by themselves. I don’t know the first thing about web applications and OpenID, so I’m really glad that Barry and Robert came up with a “hello world” kind of Flask webapp which uses Ubuntu SSO authentication to verify that the requester is an Ubuntu Developer. I implemented the input variable validation and sending the actual test requests over AMQP.

Now we have a nice autopkgtest-retrier git with the required functionality and 100% (yes, complete!) test coverage. With that, requesting tests in a local deployment works! So what’s left to do for me now is to turn this into a CGI script, configure apache for it, enable SSL on, and update the charms to set this all up automatically. So this moved from “ugh, I don’t know where to start” from “should land next week” in these three days!

We are going to have similar sprints for Brian’s error tracker, Robert’s CI train, and Barry’s system-image builder in the next weeks. Let’s increase all those bus factors from the current “1” to at least “4” ☺ . Looking forward to these!

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liam zheng


在之前的培训教程"在Ubuntu OS上创建一个dianping Scope (Qt JSON)"中,介绍了如何使用C++来在Ubuntu平台上开发一个Scope;在文章"使用golang来设计Ubuntu Scope"里也展示了如何使用go语言来在Ubuntu上开发一个Scope。今天将展示如何利用Javascript语言来开发一个Scope。这对于网页开发的开发者来说,无疑是一个好消息,不需要学习另外一种语言就可以轻松地开发一个Scope。更多关于Scope开发的知识可以在这里获得。


首先,必须强调的是Javascrip支持Scope的开发始于Ubuntu 15.04(vivid)系统及以后的版本。在开发之前,开发者必须按照文章"Ubuntu SDK 安装"安装好的SDK。同时,必须做如下的JS Scope开发工具的安装:

$ sudo apt install unity-js-scopes-dev
$ unity-js-scopes-tool setup

在这里必须注意的是,必须在安装完Ubuntu SDK后才可以执行上面的安装,并在SDK的安装中chroots必须安装完整。经过上面的安装,基本上已经完成了所有的工具的安装。


二、JS Scope开发文档

所有的开发离不开所需要的技术文档,JS Scope的开发文档的地址可以在early build找到,当然也可以通过安装unity-js-scopes-doc包来得到帮助。



A、Webservice API:



{"error":0,"status":"success","date":"2016-01-18","results":[{"currentCity":"北京","pm25":"13","index":[{"title":"穿衣","zs":"寒冷","tipt":"穿衣指数","des":"天气寒冷,建议着厚羽绒服、毛皮大衣加厚毛衣等隆冬服装。年老体弱者尤其要注意保暖防冻。"},{"title":"洗车","zs":"较适宜","tipt":"洗车指数","des":"较适宜洗车,未来一天无雨,风力较小,擦洗一新的汽车至少能保持一天。"},{"title":"旅游","zs":"一般","tipt":"旅游指数","des":"天气较好,温度稍低,而且风稍大,让您感觉有些冷,会对外出有一定影响,外出注意防风保暖。"},{"title":"感冒","zs":"极易发","tipt":"感冒指数","des":"天气寒冷,昼夜温差极大且空气湿度较大,易发生感冒,请注意适当增减衣服,加强自我防护避免感冒。"},{"title":"运动","zs":"较不宜","tipt":"运动指数","des":"天气较好,但考虑天气寒冷,风力较强,推荐您进行室内运动,若在户外运动请注意保暖并做好准备活动。"},{"title":"紫外线强度","zs":"弱","tipt":"紫外线强度指数","des":"紫外线强度较弱,建议出门前涂擦SPF在12-15之间、PA+的防晒护肤品。"}],"weather_data":[{"date":"周一 01月18日 (实时:-8℃)","dayPictureUrl":"","nightPictureUrl":"","weather":"晴","wind":"北风3-4级","temperature":"-4 ~ -11℃"},{"date":"周二","dayPictureUrl":"","nightPictureUrl":"","weather":"晴转多云","wind":"微风","temperature":"-1 ~ -8℃"},{"date":"周三","dayPictureUrl":"","nightPictureUrl":"","weather":"多云转阴","wind":"微风","temperature":"0 ~ -7℃"},{"date":"周四","dayPictureUrl":"","nightPictureUrl":"","weather":"阴转多云","wind":"微风","temperature":"-3 ~ -6℃"}]}]}




在这一节中,来练习创建一个JS Scope,可以利用在Ubuntu SDK中所提供的template来轻松地创建一个Scope。首先,打开SDK,选择"New File or Project":


显示如下,基本上没有什么特别的东西。它在默认的情况下显示的是一个天气的Scope,但可以在它里面输入一些感兴趣的城市的名称来得到当前城市的天气情况。也可以选择SDK屏幕做下角的Desktop或Ubuntu Desktop SDK kit来在Desktop的环境下运行。当在手机上运行时,必须选择Ubuntu SDK for armhf来运行:




liuxg@liuxg:~/release/chinaweatherjs$ tree
├── chinaweatherjs.apparmor
├── CMakeLists.txt
├── CMakeLists.txt.user
├── po
│   ├── chinaweatherjs.pot
│   ├── CMakeLists.txt
│   ├──
│   ├──
│   └──
└── src
    ├── chinaweatherjs.js
    ├── CMakeLists.txt
    ├── data
    │   ├──
    │   ├──
    │   ├── icon.png
    │   └── logo.png
    ├── etc
    └── node_modules
        ├── last-build-arch.txt
        └── unity-js-scopes
            ├── bin
            │   └── unity-js-scopes-launcher
            ├── index.js
            ├── lib
            │   └── scope-core.js
            └── unity_js_scopes_bindings.node

8 directories, 20 files




细心的开发者可能已经注意到一个叫做node_modules的目录,JS Scope使用的框架就是npm + Scope,可以很方便地使用unity-js-scopes-tool来加入所需要的npm包到Scope项目中去,运行的命令如下:

$ unity-js-scopes-tool install <path/to/project/src/node_modules> <npm package>





Javascript Scope的基本架构


  • 导入 Javascript Scope模块到你的代码中
  • 设置你的Scope的runtime上下文


var scopes = require('unity-js-scopes')
scopes.self.initialize({}, {});

一旦被导入,unity-js-scopes核心模块即是和Scope runtime交互的入口点,runtime可设置Scope,和Dash进行交互及显示用户在Scope交互所生产的结果等。


        get: function() {
            if (! self) {
                self = new Scope();
            return self;

除了定义一些Scope在运行时的一下runtime元素以外,runtime上下文还允许检查当前Scope的设置及接受scope runtime环境变化时所生产的变化等。


Runtime 元素


一旦Scope和runtime建立起连接并被用户所启动,scope runtime将发送来所有的由用户所产生的动作。最终这些动作将被发送到Scope在Initialize过程中所定义的API函数中。


  • run: 当一个scope准备运行时,这个回调函数将被调用.
  • start: 当一个scope准备启动时,这个函数将被调用
  • stop: 当一个scope准备停止时,这个函数将被调用
  • search: 当用户请求一个搜索时,这个函数将被调用.runtime将将提供所有的关于搜索所需要的信息给这个函数的调用.开发者的任务就是通过和runtime的交互把所有可能的结果push给runttime.你也可以控制如何显示这些结果
  • preview: 显示一个在上面search中显示结果的preview.runtime将提供关于这个preview所需要的所有的信息


var scopes = require('unity-js-scopes')
scopes.self.initialize({}, {
    run: function() {
    start: function(scope_id) {
        console.log('Starting scope id: ' + scope_id + ', ' + scopes.self.scope_config)
    search: function(canned_query, metadata) {
        return null
    preview: function(result, metadata) {
        return null

对于每一个scope runtime的回调函数来说,它相应于一个用户的交互。scope runtime希望scope发送回一个描述各个关键交互所需要的对象。


SearchQuery object可以定义一个run回调函数。当搜索发生时,该函数将被调用。同时它也可以定义一个cancel的回调函数,当一个搜索被停止时,该函数将被调用。

Scope runtime同时也传入一个叫做SearchReply的object,这个object可以被用来push一些结果到scope runtime。

上面的这种交互模式是贯穿了整个scope及scope rumtime设计的核心交互模式。



上面讲到的一个最核心的搜索交互就是scope可以把所需要的结果推送到scope runtime。这些结果是通过SearchReply来完成推送的,这个函数希望一个叫做CategorisedResult类型的数据被创建,并被推送到scope runtime。这个result对象将让我们的scope来定义诸如title, icon,uri等信息。



var query_host = ""
var weather_path = "/telematics/v3/weather?output=json&ak=DdzwVcsGMoYpeg5xQlAFrXQt&location=" 
var URI = ""; 


                search: function(canned_query, metadata) {
                    return new scopes.lib.SearchQuery(
                                // run
                                function(search_reply) {
                                    var qs = canned_query.query_string();
                                    if (!qs) {
                                        qs = "北京"

                                    console.log("query string: " + qs);

                                    var weather_cb = function(response) {
                                        var res = '';

                                        // Another chunk of data has been recieved, so append it to res
                                        response.on('data', function(chunk) {
                                            res += chunk;

                                        // The whole response has been recieved
                                        response.on('end', function() {
                                            // console.log("res: " + res);

                                            r = JSON.parse(res);

                                            // Let's get the detailed info
                                            var request_date =
                                            console.log("date: " + date);

                                            var city = r.results[0].currentCity;
                                            console.log("city: " + city);

                                            var pm25 = r.results[0].pm25
                                            console.log("pm25: " + pm25)

                                            var category_renderer = new scopes.lib.CategoryRenderer(JSON.stringify(WEATHER_TEMPLATE));
                                            var category = search_reply.register_category("Chineweather", city, "", category_renderer);

                                            try {
                                                r = JSON.parse(res);
                                                var length = r.results[0].weather_data.length
                                                console.log("length: " + length)

                                                for (var i = 0; i < length; i++) {
                                                    var categorised_result = new scopes.lib.CategorisedResult(category);

                                                    var date = r.results[0].weather_data[i].date
                                                    console.log("date: "+  date);

                                                    var dayPictureUrl = r.results[0].weather_data[i].dayPictureUrl;
                                                    console.log("dayPictureUrl: " + dayPictureUrl);

                                                    var nightPictureUrl = r.results[0].weather_data[i].nightPictureUrl;
                                                    console.log("nightPictureUrl: " + nightPictureUrl);

                                                    var weather = r.results[0].weather_data[i].weather;
                                                    console.log("weather: " + weather);

                                                    var wind = r.results[0].weather_data[i].wind;
                                                    console.log("wind: " + wind);

                                                    var temperature = r.results[0].weather_data[i].temperature;
                                                    console.log("temperature: " + temperature);

                                                    categorised_result.set("weather", weather);
                                                    categorised_result.set("wind", wind);
                                                    categorised_result.set("temperature", temperature);

                                                    categorised_result.set_title("白天: " + date );
                                                    categorised_result.set("subtitle", weather);

                                                    categorised_result.set_title("夜晚: " + date );


                                                // We are done, call finished() on our search_reply
//                                              search_reply.finished();
                                            catch(e) {
                                                // Forecast not available
                                                console.log("Forecast for '" + qs + "' is unavailable: " + e)

                                    console.log("request string: " + query_host + weather_path + qs);

                                    http.request({host: query_host, path: weather_path + encode_utf8(qs)}, weather_cb).end();

                                // cancelled
                                function() {



一旦搜索结果被推送到scope runtime并被显示,用户可以点击显示的结果并请求一个关于该结果的preview.Scope runtime将通过scope中所定义的preview回调来显示所需要的结果.


就像上面对search所描述的那样,scope runtime希望的scope返回一个PreViewQuery的对象来作为一个交互的桥梁。这个对象必须指定一个run及一个cancel的函数.这两个函数和上面介绍的search中的语义是一样的。这里不再累述。


对Preview来说,有两个最重要的元素:column layout及Preview Widgets。就像它们的名字所描述的那样,column layout元素是用来定义Preview页面中Preview Component的layout的。Preview Widget是用来在Preview页面中组成页面的。



  preview: function(result, action_metadata) {
                    return new scopes.lib.PreviewQuery(
                                // run
                                function(preview_reply) {
                                    var layout1col = new scopes.lib.ColumnLayout(1);
                                    var layout2col = new scopes.lib.ColumnLayout(2);
                                    var layout3col = new scopes.lib.ColumnLayout(3);
                                    layout1col.add_column(["imageId", "headerId", "temperatureId", "windId"]);

                                    layout2col.add_column(["headerId", "temperatureId", "windId"]);

                                    layout3col.add_column(["headerId", "temperatureId", "windId"]);

                                    preview_reply.register_layout([layout1col, layout2col, layout3col]);

                                    var header = new scopes.lib.PreviewWidget("headerId", "header");
                                    header.add_attribute_mapping("title", "title");
                                    header.add_attribute_mapping("subtitle", "subtitle");

                                    var image = new scopes.lib.PreviewWidget("imageId", "image");
                                    image.add_attribute_mapping("source", "art");

                                    var temperature = new scopes.lib.PreviewWidget("temperatureId", "text");
                                    temperature.add_attribute_mapping("text", "temperature");

                                    var wind = new scopes.lib.PreviewWidget("windId", "text");
                                    wind.add_attribute_mapping("text", "wind");

                                    preview_reply.push([image, header, temperature, wind ]);
                                // cancelled
                                function() {




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Dustin Kirkland


  • Put /tmp on tmpfs and you'll improve your Linux system's I/O, reduce your carbon foot print and electricity usage, stretch the battery life of your laptop, extend the longevity of your SSDs, and provide stronger security.
  • In fact, we should do that by default on Ubuntu servers and cloud images.
  • Having tested 502 physical and virtual servers in production at Canonical, 96.6% of them could immediately fit all of /tmp in half of the free memory available and 99.2% could fit all of /tmp in (free memory + free swap).

Try /tmp on tmpfs Yourself

$ echo "tmpfs /tmp tmpfs rw,nosuid,nodev" | sudo tee -a /etc/fstab
$ sudo reboot


In April 2009, I proposed putting /tmp on tmpfs (an in memory filesystem) on Ubuntu servers by default -- under certain conditions, like, well, having enough memory. The proposal was "approved", but got hung up for various reasons.  Now, again in 2016, I proposed the same improvement to Ubuntu here in a bug, and there's a lively discussion on the ubuntu-cloud and ubuntu-devel mailing lists.

The benefits of /tmp on tmpfs are:
  • Performance: reads, writes, and seeks are insanely fast in a tmpfs; as fast as accessing RAM
  • Security: data leaks to disk are prevented (especially when swap is disabled), and since /tmp is its own mount point, we should add the nosuid and nodev options (and motivated sysadmins could add noexec, if they desire).
  • Energy efficiency: disk wake-ups are avoided
  • Reliability: fewer NAND writes to SSD disks
In the interest of transparency, I'll summarize the downsides:
  • There's sometimes less space available in memory, than in your root filesystem where /tmp may traditionally reside
  • Writing to tmpfs could evict other information from memory to make space
You can learn more about Linux tmpfs here.

Not Exactly Uncharted Territory...

Fedora proposed and implemented this in Fedora 18 a few years ago, citing that Solaris has been doing this since 1994. I just installed Fedora 23 into a VM and confirmed that /tmp is a tmpfs in the default installation, and ArchLinux does the same. Debian debated doing so, in this thread, which starts with all the reasons not to put /tmp on a tmpfs; do make sure you read the whole thread, though, and digest both the pros and cons, as both are represented throughout the thread.

Full Data Treatment

In the current thread on ubuntu-cloud and ubuntu-devel, I was asked for some "real data"...

In fact, across the many debates for and against this feature in Ubuntu, Debian, Fedora, ArchLinux, and others, there is plenty of supposition, conjecture, guesswork, and presumption.  But seeing as we're talking about data, let's look at some real data!

Here's an analysis of a (non-exhaustive) set of 502 of Canonical's production servers that run,, and hundreds of related services, including OpenStack, dozens of websites, code hosting, databases, and more. These servers sampled are slightly biased with more physical machines than virtual machines, but both are present in the survey, and a wide variety of uptime is represented, from less than a day of uptime, to 1306 days of uptime (with live patched kernels, of course).  Note that this is not an exhaustive survey of all servers at Canonical.

I humbly invite further study and analysis of the raw, tab-separated data, which you can find at:
The column headers are:
  • Column 1: The host names have been anonymized to sequential index numbers
  • Column 2: `du -s /tmp` disk usage of /tmp as of 2016-01-17 (ie, this is one snapshot in time)
  • Column 3-8: The output of the `free` command, memory in KB for each server
  • Column 9-11: The output of the `free` command, sway in KB for each server
  • Column 12: The number of inodes in /tmp
I have imported it into a Google Spreadsheet to do some data treatment. You're welcome to do the same, or use the spreadsheet of your choice.

For the numbers below, 1 MB = 1000 KB, and 1 GB = 1000 MB, per Wikipedia. (Let's argue MB and MiB elsewhere, shall we?)  The mean is the arithmetic average.  The median is the middle value in a sorted list of numbers.  The mode is the number that occurs most often.  If you're confused, this article might help.  All calculations are accurate to at least 2 significant digits.

Statistical summary of /tmp usage:

  • Max: 101 GB
  • Min: 4.0 KB
  • Mean: 453 MB
  • Median: 16 KB
  • Mode: 4.0 KB
Looking at all 502 servers, there are two extreme outliers in terms of /tmp usage. One server has 101 GB of data in /tmp, and the other has 42 GB. The latter is a very noisy django.log. There are 4 more severs using between 10 GB and 12 GB of /tmp. The remaining 496 severs surveyed (98.8%) are using less than 4.8 GB of /tmp. In fact, 483 of the servers surveyed (96.2%) use less than 1 GB of /tmp. 454 of the servers surveyed (90.4%) use less than 100 MB of /tmp. 414 of the servers surveyed (82.5%) use less than 10 MB of /tmp. And actually, 370 of the servers surveyed (73.7%) -- the overwhelming majority -- use less than 1MB of /tmp.

Statistical summary of total memory available:

  • Max: 255 GB
  • Min: 1.0 GB
  • Mean: 24 GB
  • Median: 10.2 GB
  • Mode: 4.1 GB
All of the machines surveyed (100%) have at least 1 GB of RAM.  495 of the machines surveyed (98.6%) have at least 2GB of RAM.   437 of the machines surveyed (87%) have at least 4 GB of RAM.   255 of the machines surveyed (50.8%) have at least 10GB of RAM.    157 of the machines surveyed (31.3%) have more than 24 GB of RAM.  74 of the machines surveyed (14.7%) have at least 64 GB of RAM.

Statistical summary of total swap available:

  • Max: 201 GB
  • Min: 0.0 KB
  • Mean: 13 GB
  • Median: 6.3 GB
  • Mode: 2.96 GB
485 of the machines surveyed (96.6%) have at least some swap enabled, while 17 of the machines surveyed (3.4%) have zero swap configured. One of these swap-less machines is using 415 MB of /tmp; that machine happens to have 32 GB of RAM. All of the rest of the swap-less machines are using between 4 KB and 52 KB (inconsequential) /tmp, and have between 2 GB and 28 GB of RAM.  5 machines (1.0%) have over 100 GB of swap space.

Statistical summary of swap usage:

  • Max: 19 GB
  • Min: 0.0 KB
  • Mean: 657 MB
  • Median: 18 MB
  • Mode: 0.0 KB
476 of the machines surveyed (94.8%) are using less than 4 GB of swap. 463 of the machines surveyed (92.2%) are using less than 1 GB of swap. And 366 of the machines surveyed (72.9%) are using less than 100 MB of swap.  There are 18 "swappy" machines (3.6%), using 10 GB or more swap.

Modeling /tmp on tmpfs usage

Next, I took the total memory (RAM) in each machine, and divided it in half which is the default allocation to /tmp on tmpfs, and subtracted the total /tmp usage on each system, to determine "if" all of that system's /tmp could actually fit into its tmpfs using free memory alone (ie, without swap or without evicting anything from memory).

485 of the machines surveyed (96.6%) could store all of their /tmp in a tmpfs, in free memory alone -- i.e. without evicting anything from cache.

Now, if we take each machine, and sum each system's "Free memory" and "Free swap", and check its /tmp usage, we'll see that 498 of the systems surveyed (99.2%) could store the entire contents of /tmp in tmpfs free memory + swap available. The remaining 4 are our extreme outliers identified earlier, with /tmp usages of [101 GB, 42 GB, 13 GB, 10 GB].

Performance of tmpfs versus ext4-on-SSD

Finally, let's look at some raw (albeit rough) read and write performance numbers, using a simple dd model.

My /tmp is on a tmpfs:
kirkland@x250:/tmp⟫ df -h .
Filesystem Size Used Avail Use% Mounted on
tmpfs 7.7G 2.6M 7.7G 1% /tmp

Let's write 2 GB of data:
kirkland@x250:/tmp⟫ dd if=/dev/zero of=/tmp/zero bs=2G count=1
0+1 records in
0+1 records out
2147479552 bytes (2.1 GB) copied, 1.56469 s, 1.4 GB/s

And let's write it completely synchronously:
kirkland@x250:/tmp⟫ dd if=/dev/zero of=./zero bs=2G count=1 oflag=dsync
0+1 records in
0+1 records out
2147479552 bytes (2.1 GB) copied, 2.47235 s, 869 MB/s

Let's try the same thing to my Intel SSD:
kirkland@x250:/local⟫ df -h .
Filesystem Size Used Avail Use% Mounted on
/dev/dm-0 217G 106G 100G 52% /

And write 2 GB of data:
kirkland@x250:/local⟫ dd if=/dev/zero of=./zero bs=2G count=1
0+1 records in
0+1 records out
2147479552 bytes (2.1 GB) copied, 7.52918 s, 285 MB/s

And let's redo it completely synchronously:
kirkland@x250:/local⟫ dd if=/dev/zero of=./zero bs=2G count=1 oflag=dsync
0+1 records in
0+1 records out
2147479552 bytes (2.1 GB) copied, 11.9599 s, 180 MB/s

Let's go back and read the tmpfs data:
kirkland@x250:~⟫ dd if=/tmp/zero of=/dev/null bs=2G count=1
0+1 records in
0+1 records out
2147479552 bytes (2.1 GB) copied, 1.94799 s, 1.1 GB/s

And let's read the SSD data:
kirkland@x250:~⟫ dd if=/local/zero of=/dev/null bs=2G count=1
0+1 records in
0+1 records out
2147479552 bytes (2.1 GB) copied, 2.55302 s, 841 MB/s

Now, let's create 10,000 small files (1 KB) in tmpfs:
kirkland@x250:/tmp/foo⟫ time for i in $(seq 1 10000); do dd if=/dev/zero of=$i bs=1K count=1 oflag=dsync ; done
real 0m15.518s
user 0m1.592s
sys 0m7.596s

And let's do the same on the SSD:
kirkland@x250:/local/foo⟫ time for i in $(seq 1 10000); do dd if=/dev/zero of=$i bs=1K count=1 oflag=dsync ; done
real 0m26.713s
user 0m2.928s
sys 0m7.540s

For better or worse, I don't have any spinning disks, so I couldn't repeat the tests there.

So on these rudimentary read/write tests via dd, I got 869 MB/s - 1.4 GB/s write to tmpfs and 1.1 GB/s read from tmps, and 180 MB/s - 285 MB/s write to SSD and 841 MB/s read from SSD.

Surely there are more scientific ways of measuring I/O to tmpfs and physical storage, but I'm confident that, by any measure, you'll find tmpfs extremely fast when tested against even the fastest disks and filesystems.


  • /tmp usage
    • 98.8% of the servers surveyed use less than 4.8 GB of /tmp
    • 96.2% use less than 1.0 GB of /tmp
    • 73.7% use less than 1.0 MB of /tmp
    • The mean/median/mode are [453 MB / 16 KB / 4 KB]
  • Total memory available
    • 98.6% of the servers surveyed have at least 2.0 GB of RAM
    • 88.0% have least 4.0 GB of RAM
    • 57.4% have at least 8.0 GB of RAM
    • The mean/median/mode are [24 GB / 10 GB / 4 GB]
  • Swap available
    • 96.6% of the servers surveyed have some swap space available
    • The mean/median/mode are [13 GB / 6.3 GB / 3 GB]
  • Swap used
    • 94.8% of the servers surveyed are using less than 4 GB of swap
    • 92.2% are using less than 1 GB of swap
    • 72.9% are using less than 100 MB of swap
    • The mean/median/mode are [657 MB / 18 MB / 0 KB]
  • Modeling /tmp on tmpfs
    • 96.6% of the machines surveyed could store all of the data they currently have stored in /tmp, in free memory alone, without evicting anything from cache
    • 99.2% of the machines surveyed could store all of the data they currently have stored in /tmp in free memory + free swap
    • 4 of the 502 machines surveyed (0.8%) would need special handling, reconfiguration, or more swap


  • Can /tmp be mounted as a tmpfs always, everywhere?
    • No, we did identify a few systems (4 out of 502 surveyed, 0.8% of total) consuming inordinately large amounts of data in /tmp (101 GB, 42 GB), and with insufficient available memory and/or swap.
    • But those were very much the exception, not the rule.  In fact, 96.6% of the systems surveyed could fit all of /tmp in half of the freely available memory in the system.
  • Is this the first time anyone has suggested or tried this as a Linux/UNIX system default?
    • Not even remotely.  Solaris has used tmpfs for /tmp for 22 years, and Fedora and ArchLinux for at least the last 4 years.
  • Is tmpfs really that much faster, more efficient, more secure?
    • Damn skippy.  Try it yourself!

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Rae Shambrook

In the coming months, users will start noticing things looking more and more different on Ubuntu. As we gradually roll out our new and improved Suru visual language, you’ll see apps and various other bits of the platform take on a lighter, more clean and cohesive look.

Why refresh apps at all?

As Ubuntu brings convergence to life—embracing today’s as well as future devices—our visual style and UI Toolkit need to evolve to support the new world. The changes taking place platform-wide make it simpler for designers and developers to integrate convergence from inception, and help apps come to life equally on mobile or desktop without a lot of additional work. As we apply new convergence UI and UX patterns to general-purpose components like lists and checkboxes, we also seek out opportunities to work with community developers and designers to put the thinking and new components into practice. The Clock app has been one such opportunity.



The Redesign

Our clean, crisp and lucid Suru visual language and style works well with the added functionality required for convergence. There’s less visual distraction and noise than ever, providing a clear pathway to making the most of the new toolkit’s convergence functionality.

Our Suru visual design language is based on origami, with graphic elements containing meaningful folds and shadows to create the illusion of paper and draw focus to certain areas. Using the main clock face’s current animation (where the clock flips from analog to digital on touch) as inspiration, it seemed natural to place a fold in the middle of the clock. On touch, the clock “folds” from analog to digital.


To further the paper look, drop shadows are used to give the illusion of layers of paper. The shadow under the clock face elevates it from the page, adding a second layer. The drop shadows on the clock hands add yet another layer.

As for colours, the last clock design featured a grey and purple scheme. In our new design, we make use of our very soon-to-be released new color palette. We brightened the interface with a white background and light grey clock face. On the analog clock, the hour and second hands are now Ubuntu orange. With the lighter UI, this subtle use of branding is allowed to stand out more. Also, the purple text is gone in favor of a more readable dark grey.

The bottom edge hint has also been redesigned. The new design is much more minimal, letting users get used to the gesture without interrupting the content too much.

In the stopwatch section, the fold is absent from the clock face since the element is static. We also utilize our new button styling. In keeping with the origami theme, the buttons now have a subtle drop shadow rather than an inward shadow, to again create a more “paper” feel.


This project has been one of my favorites so far. Although it wasn’t a complete redesign (the functionality remains the same) it was fun seeing how the clock would evolve next. Hope you enjoy the new version of the clock, it’s currently in development so look out for it on your phones soon and stay tuned for more visual changes.

Visual Design: Rae Shambrook

UX Design: James Mulholland


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David Callé

Today we announce the launch of our second Ubuntu Scopes Showdown! We are excited to bring you yet another engaging developer competition, where the Ubuntu app developer community brings innovative and interesting new experiences for Ubuntu on mobile devices.

Scopes in Javascript and Go were introduced recently and are the hot topic of this competition!

Contestants will have six weeks to build and publish their Unity8 scopes to the store using the Ubuntu SDK and Scopes API (JavaScript, Go or C++), starting Monday January 18th.

A great number of exciting prizes are up for grabs: a System76 Meerkat computer, BQ E5 Ubuntu phones, Steam Controllers, Steam Link, Raspberry Pi 2 and convergence packs for Ubuntu phones!

Find out more details on how to enter the competition. Good luck and get developing! We look forward to seeing your scopes on our Ubuntu homescreens!

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Daniel Holbach

I can’t wait for UbuCon Summit to start. The list of attendees is growing and with some of the folks it’s been ages since I met them in person the last time. For me that’s the number one reason to be there. Catching up with everyone will be great.

The schedule for UbuCon Summit is looking fantastic as well. We have many many great talks and demos lined up from a really broad spectrum, there’s going to be much to learn about and there’s going to be more surprises coming up in the unconference part of UbuCon.

And there’s more:

Anything I missed you’re looking forward to? Let me know in the comments. :-)

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(there is an English version of this post, here)

Python tiene una biblioteca estándar muy extensa ("viene con las pilas incluídas"), pero es frecuente la necesidad de usar otros módulos que están afuera de la misma, casi siempre desde el Índice de Paquetes de Python (PyPI).

La manera original de instalar esos módulos es a "nivel de sistema" (sudo pip install foobar), en el sistema operativo de forma general, habilitándolos para ser utilizados por cualquier programa que se ejecute.

Más allá de necesitar permisos de root o administrador para instalar las dependencias de esta manera, el primer problema con el que nos encontramos es el de conflictos: el caso típico de dos programas que necesitan la misma dependencia pero en versiones distintas, lo cual no puede lograrse al instalar las dependencias en forma global.

Por eso es que es tan normal en el mundo de Python usar "entornos virtuales". Se crea un entorno virtual para cada programa, se instala las dependencias necesarias para cada programa en cada entorno virtual, y como lo que instalamos en ese entorno es sólo accesible desde dentro del entorno, no hay más conflictos.

En este punto, sin embargo, aparece el problema de la administración de los entornos virtuales: crearlos, instalarles cosas, activarlos para usarlos con cada programa y desactivarlos luego, recordar los nombres de cada entorno para cada programa, etc.

Para automatizar esto nació fades.

fades les permite utilizar todo el poder de los entornos virtuales sin tener que preocuparse por ellos.

¿Quieren ejecutar un script que necesita la dependencia foobar?

    fades -d foobar

¿Quieren un intérprete interactivo teniendo foobar instalado como dependencia?

    fades -d foobar

¿Necesitan ejecutar el script pero con varias dependencias, alguna en una versión específica?

    fades -d foo -d bar -d baz==1.1

¿Tienen todas las dependencias en un archivo de requerimientos?

    fades -r requirements.txt

Esto es sólo lo más sencillo que podés hacer con fades. Los entornos virtuales son una herramienta poderosísima, y automatizar y simplificar su uso hace que fades tenga bastantes opciones, algunas que usarán todos los días, y otras que les van a resultar muy útiles en casos puntuales.

Empiecen a usar fades de a poco (acá tienen toda la documentación) y van a encontrar que van a tener resuelto el tema de la administración de dependencias en programas y scripts, usando entornos virtuales pero sin la complejidad de tener que hacerlo directamente y a mano.

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Colin Ian King

While looking at some code in the Linux Kernel this morning I spotted a few FIXME comments and that got me wondering just how many there are in the source code.  After a quick grep I found nearly 4200 in v4.4.0-rc8 and that got me thinking about other similar comment tags such as TODO that are in the source and how this has been changing over time.

So the trends are certainly upwards, but then again, so is the size of the kernel source:

Note: Data gathered using sloccount on the lines of C in the kernel source.

Using the sloccount data I then calculated the number of FIXME and TODOs per 1000 lines of code to see what the underlying trend is:

So FIXMEs are actually dropping in relative terms to the size of the kernel where as TODOs are increasing.

Of course, these statistics are bogus because it is dependent on kernel developers adding and removing FIXMEs and TODOs in a consistent manner, however, it is interesting to see how many comments exist and hence how much work has been tagged in comments as work to be done later. I wonder how this compares to other large open source projects.

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Para arrancar el año pum para arriba, ¿qué mejor que una nueva versión de Encuentro?

Lo más destacado de esta nueva versión es que hay dos backends nuevos!

Por un lado, ahora se puede descargar de Contenidos Digitales Abiertos (también conocido como CDA), con casi 4000 episodios de centenares de documentales y series para mirar.

Por otro lado, trae más de 180 charlas TED del capítulo TEDx de Buenos Aires (que incluye TEDxBuenosAires, TEDxRíodelaPlata, TEDxJoven, y un par más).


También tiene varias mejoras importantes, como que se limpian los nombres de archivos para que puedan ser grabados en cualquier lado (pen drives, fat32, etc), o que rearmé el esquema de downloads y ahora es mucho mucho más robusto que antes. E incluso estuve mejorando los scrappers para backends que ya estaban incluidos en versiones anteriores, pero ahora tendrán mejores títulos, nombres más prolijos, etc.

Y claro, varias correcciones menores también, y seguramente algún par de bugs nuevos :p.

Las instrucciones para bajar Encuentro en tu sistema (Debian, Ubuntu, Arch, Windows, o cualquier otro sistema), junto con el detalle de los cambios, instrucciones, y todo eso, en la página del proyecto.


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When Internet of Things devices debut at this year’s CES, one of the biggest questions will be how they’ll connect to all the other smart-home gear on display. But anyone who expects a clear answer to that is like a kid who gets up Thanksgiving morning looking for a bunch of gifts under a tree.

The fact is, it’s too early to say what standard or protocol will become the glue that can turn a pile of cool gadgets into a system that runs your whole house for you. New systems are just starting to emerge, and though they may eventually work with each other and with older platforms, buying one of each and expecting harmony is still wishful thinking.

Connected homes may make life easier eventually. A thermostat linked to a garage-door opener could tell who’s coming home and set the heat or air-conditioning for their preferences. Compatible room lights and an audio system could join in, too.

Read More:


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Colin Ian King

While developing stress-ng I wanted to be able to see if the various memory stressors were touching memory in the way I had anticipated.  While digging around in the Linux documentation I discovered the very useful soft/dirty bit on Page Table Entries (PTEs) that get set when a page is written to.  The mechanism to check for the soft/dirty bit is described in Documentation/vm/soft-dirty.txt; one needs to:

  1. Clear the soft-dirty bits on the PTEs on a chosen process by writing "4" to /proc/$PID/clear_refs
  2. Wait a while for some page activity to occur
  3. Read the soft-dirty bits on the PTEs to see which pages got written to.
Not too tricky, so how about using this neat feature? While on rather long and dull flight over the Atlantic back in August I hacked up a very crude ncurses based tool to continually check the PTEs of a given process and display the soft/dirty activity in real time.  During this Christmas break I picked this code up and re-worked into a more polished tool.  One can scroll up/down the memory maps and also select a page and view the contents changing in real time.  The tool identifies the type of memory mapping a page belongs to, so one can easily scan through memory looking at pages of memory belonging data, code, heap, stack, anonymous mappings or even swapped out pages.

Running it on X, compiz, firefox or thunderbird is quite instructive as one can see a lot of page activity on the large heap allocations.  The ability to see pages getting swapped out when memory pressure is high is also rather useful.

Page view of Xorg
Memory view of stack
The code is still early development quality (so expect some buglets!) and I need to work on optimising it in a lot of places, but for now, it works well enough to be a fairly interesting tool. I've currently got a package built for Ubuntu Xenial in ppa:colin-king/pagemon and the source can be cloned from

So, to install on Xenial, currently one needs to do:

sudo add-apt-repository ppa:colin-king/pagemon
sudo apt-get update
sudo apt-get install pagemon

I may be adding a few more features in the next few weeks, and then getting the tool into Ubuntu and Debian.

and as an example, running it on Xorg, it is invoked as:

sudo pagemon -p $(pidof Xorg)

Unfortunately sudo is required to allow one to dig so intrusively into a running process. For more details on how to use pagemon consult the pagemon man page, or press "h" or "?" while running pagemon.

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Refresh de pelis de fin de año

Buena temporada para ver películas fue. Muchas vistas, pero con resultados variados... mucho voto negativo, y un sólo +1!

  • Beginners: +0. Linda película sobre la aceptación de lo que uno es. Muy buenas actuaciones, y lindo como está contada.
  • Chef: +1. Linda película sobre la búsqueda de lo que te divierte hacer y vivir. Imperdible si te gusta cocinar o ver cocinar.
  • Drinking Buddies: +0. Relaciones humanas, tan difíciles. Esta peli muesta un lado que no siempre se explicita, entre la amistad y la atracción, muy buena.
  • Edge of Tomorrow: +0. No es Groundhog Day, pero está bien tratado el tema. Y el resto de la peli divierte, pero termina siendo sólo una peli de acción.
  • Guardians of the Galaxy: -0. Todo lo que es construcción de bichos o mundos extraterrestres, está muy bien, y tiene bastantes partes con buen humor... pero el resto es muy childish, no termina de armar una película en serio.
  • Her: +0. Una buena historia, destacando que las relaciones humanas son siempre desde el punto de vista de las partes que componen la relación.
  • I Give It a Year: +0. Una comedia romántica suave. Todo predecible, nada particularmente interesante, pero vale la pena si estás buscando algo pasatista.
  • In a World...: -0. Una comedia semi-romántica, con nada especialmente interesante para destacar.
  • Leonera: +0. Cruda y fuerte como todas las de Trapero, pero es más importante la historia, que está buena.
  • Lucy: -0. Tiene partes muy interesantes, pero es demasiado flashera, demasiado... poco sustentable.
  • Mindscape: +0. Un thriller que te tiene hasta último momento tratando de entender lo que pasa. Me gustan las pelis así, especialmente cuando al final explican todo :)
  • Non-Stop: -0. Tiene algunos giros interesantes, y un suspenso y una resolución que fueron lo que me llevaron a verla... pero realmente, todo termina en un "suave" que no vale la pena :/
  • Out of the Furnace: -0. Con buenos actores, y aunque la historia está bien, deja demasiada cosas sin explicar o a medio sugerir.
  • Passion: -0. La historia podría estar buena... pero está mal "contada", las situaciones están mal llevadas, no tiene ritmo. Y el final... bleh.
  • Primer: -0. Interesante, pero muy rebuscada. Aplica un concepto que está piola, pero le sobra mucho alrededor y finalmente no explica bien lo que pasa.
  • Sabotage: -0. Tiene sus momentos interesantes, el misterio, la dinámica de algunas personas, la violencia cruda... pero no suma. No suma.
  • Sin City: A Dame to Kill For: -0. La fotografía es simplemente maravillosa, impecable, exhuberante... pero no tiene mucha historia, y es muy monótono todo.
  • The Family: +0. Típica comedia de gangsters, sin muchas pretensiones pero divertida :)
  • The Grand Budapest Hotel: +0. Bizarra, divertida, dinámica. Me gustó mucho la forma en que está contada, y la fotografía es GENIAL. Alta concentración de actores buenos, también...
  • The Kitchen: -0. Tiene sus momentos que valen algo, y es interesante la dinámica de filmar todo desde una habitación, pero no mucho más.
  • The Lifeguard: +0. Una linda historia sobre la búsqueda de qué ser, de que hacer con la vida.
  • Wakolda: +0. Interesante historia (no sé cuanto de verídica), buena peli.
  • X-Men: Days of Future Past: -0. Por momentos interesante, especialmente el juego de pasado/futuro, pero más de lo mismo, y aburre que no haya nada nuevo. Demasiado pasatista.

También muchas nuevas anotadas para ver...

  • Air (2015; Sci-Fi, Thriller) In the near future, breathable air is nonexistent. Virtually all of humanity has disappeared and those chosen to reestablish society reside in a controlled state of suspended animation. Two engineers (Norman Reedus and Djimon Hounsou) tasked with guarding the last hope for mankind struggle to preserve their own sanity and lives while administering to their vital task at hand. [D: Christian Cantamessa; A: Norman Reedus, Djimon Hounsou, Sandrine Holt]
  • Alice Through the Looking Glass (2016; Adventure, Family, Fantasy) When Alice wakes up in Wonderland she must travel through a mysterious new world to retrieve a magical scepter that can stop the evil Lord of Time before he turns forward the clock and turns Wonderland into a barren, lifeless old world. With the help of some new friends, Alice must also uncover an evil plot to put the Queen of Hearts back on the throne. [D: James Bobin; A: Johnny Depp, Anne Hathaway, Alan Rickman]
  • Amnesiac (2015; Drama, Horror, Mystery, Thriller) The story of a man who wakes up in bed suffering from memory loss after being in an accident, only to begin to suspect that his wife may not be his real wife and that a web of lies and deceit deepen inside the house where he soon finds himself a prisoner. [D: Michael Polish; A: Kate Bosworth, Wes Bentley, Olivia Rose Keegan]
  • Anesthesia (2015; Drama, Thriller) Philosophy professor Walter Zarrow is wounded during a mugging. In an effort to escape he rings buzzers indiscriminately, waking Sam, a middle aged father of two having an affair in the city. Sam reluctantly answers Zarrow's pleas, and Zarrow loses consciousness in his arms. Through an exploration of why these men, along with the mugger, and an addict named Joe, come together, we explore New York City. The experience of Zarrow, Sam, Joe and Zarrow's assailant ripple quickly out to include the connected lives of a housewife struggling with alcoholism, a stoner teen desperate to lose his virginity, a brilliant but failed writer fighting addiction, two parents confronting the prospect of terminal illness, and a brilliant grad student who wounds herself to feel alive. [D: Tim Blake Nelson; A: David Aaron Baker, Derrick Baskin, Jacqueline Baum]
  • Black Mass (2015; Biography, Crime, Drama) John Connolly and James "Whitey" Bulger grew up together on the streets of South Boston. Decades later, in the late 1970s, they would meet again. By then, Connolly was a major figure in the FBI's Boston office and Whitey had become godfather of the Irish Mob. What happened between them - a dirty deal to trade secrets and take down Boston's Italian Mafia in the process - would spiral out of control, leading to murders, drug dealing, racketeering indictments, and, ultimately, to Bulger making the FBI's Ten Most Wanted List. [D: Scott Cooper; A: Johnny Depp, Joel Edgerton, Benedict Cumberbatch]
  • Chloe & Theo (2015; Comedy, Drama) Theo, an Inuit from the Arctic, travels to New York City to warn world leaders about the catastrophic impact of global warming on the planet. Upon arrival he meets a homeless girl named Chloe, who has an unusual vigor for life, is mildly delusional, and completely obsessed by Bruce Lee. Together, they will save the world. [D: Ezna Sands; A: Theo Ikummaq, Dakota Johnson, Mira Sorvino]
  • Deadpool (2016; Action, Adventure, Sci-Fi, Thriller) Based upon Marvel Comics most unconventional anti-hero, DEADPOOL tells the origin story of former Special Forces operative turned mercenary Wade Wilson, who after being subjected to a rogue experiment that leaves him with accelerated healing powers, adopts the alter ego Deadpool. Armed with his new abilities and a dark, twisted sense of humor, Deadpool hunts down the man who nearly destroyed his life. [D: Tim Miller; A: Morena Baccarin, Gina Carano, Ryan Reynolds]
  • Experimenter (2015; Biography, Drama, History) Experimenter is based on the true story of famed social psychologist Stanley Milgram, who in 1961 conducted a series of radical behavior experiments that tested ordinary humans willingness to obey by using electric shock. We follow Milgram, from meeting his wife Sasha through his controversial experiments that sparked public outcry. [D: Michael Almereyda; A: Winona Ryder, Taryn Manning, Kellan Lutz]
  • Hail, Caesar! (2016; Comedy, Drama, Musical) A Hollywood fixer in the 1950s works to keep the studio's stars in line. [D: Ethan Coen, Joel Coen; A: Scarlett Johansson, Channing Tatum, Ralph Fiennes]
  • Jane Got a Gun (2016; Action, Drama, Western) Jane Got a Gun centers on Jane Hammond, who has built a new life with her husband Bill "Ham" Hammond after being tormented by the ultra-violent Bishop Boys outlaw gang. She finds herself in the gang's cross-hairs once again when Ham stumbles home riddled with bullets after dueling with the Boys and their relentless mastermind Colin. With the vengeful crew hot on Ham's trail, Jane has nowhere to turn but to her former fiancé Dan Frost for help in defending her family against certain destruction. Haunted by old memories, Jane's past meets the present in a heart-stopping battle for survival. [D: Gavin O'Connor; A: Natalie Portman, Ewan McGregor, Rodrigo Santoro]
  • Momentum (2015; Action, Thriller) Alex, a mysterious thief, is pulled in by her former partner for one last heist. She quickly finds it was never just about the diamonds. A brutal murder sparks a cat and mouse chase between Alex and a master assassin. Now she must uncover the lies behind the heist and discover the secrets behind the men who have made her a target. [D: Stephen S. Campanelli; A: Olga Kurylenko, Morgan Freeman, James Purefoy]
  • Now You See Me 2 (2016; Action, Comedy, Thriller) One year after outwitting the FBI and winning the public's adulation with their Robin Hood-style magic spectacles, The Four Horsemen resurface for a comeback performance in hopes of exposing the unethical practices of a tech magnate. The man behind their vanishing act is none other than Walter Mabry, a tech prodigy who threatens the Horsemen into pulling off their most impossible heist yet. Their only hope is to perform one last unprecedented stunt to clear their names and reveal the mastermind behind it all. [D: Jon M. Chu; A: Daniel Radcliffe, Lizzy Caplan, Michael Caine]
  • Rock the Kasbah (2015; Comedy, Music) A down-on-his-luck music manager discovers a teenage girl with an extraordinary voice while on a music tour in Afghanistan and takes her to Kabul to compete on the popular television show, Afghan Star. [D: Barry Levinson; A: Bill Murray, Bruce Willis, Kate Hudson]
  • Sleeping with Other People (2015; Comedy) A good-natured womanizer and a serial cheater form a platonic relationship that helps reform them in ways, while a mutual attraction sets in. [D: Leslye Headland; A: Alison Brie, Jason Sudeikis, Jordan Carlos]
  • Snowden (2016; Biography, Drama, Thriller) SNOWDEN stars Joseph Gordon-Levitt and is written and directed by Oliver Stone. The script is based on the books The Snowden Files: The Inside Story of the World's Most Wanted Man by Luke Harding and Time of the Octopus by Anatoly Kucherena. [D: Oliver Stone; A: Shailene Woodley, Scott Eastwood, Joseph Gordon-Levitt]
  • Spectre (2015; Action, Adventure, Thriller) A cryptic message from the past sends James Bond on a rogue mission to Mexico City and eventually Rome, where he meets Lucia, the beautiful and forbidden widow of an infamous criminal. Bond infiltrates a secret meeting and uncovers the existence of the sinister organisation known as SPECTRE. Meanwhile back in London, Max Denbigh, the new head of the Centre of National Security, questions Bond's actions and challenges the relevance of MI6 led by M. Bond covertly enlists Moneypenny and Q to help him seek out Madeleine Swann, the daughter of his old nemesis Mr White, who may hold the clue to untangling the web of SPECTRE. As the daughter of the assassin, she understands Bond in a way most others cannot. As Bond ventures towards the heart of SPECTRE, he learns a chilling connection between himself and the enemy he seeks. [D: Sam Mendes; A: Daniel Craig, Christoph Waltz, Léa Seydoux]
  • Star Trek Beyond (2016; Action, Adventure, Sci-Fi, Thriller) The plot is unknown at this time. [D: Justin Lin; A: Simon Pegg, Chris Pine, Idris Elba]
  • Star Wars: The Force Awakens (2015; Action, Adventure, Fantasy, Sci-Fi) 30 years after the defeat of Darth Vader and the Empire, Rey, a scavenger from the planet Jakku, finds a BB-8 droid that knows the whereabouts of the long lost Luke Skywalker. Rey, as well as a rogue stormtrooper and two smugglers, are thrown into the middle of a battle between the resistance and the daunting legions of the First Order. [D: J.J. Abrams; A: Harrison Ford, Mark Hamill, Carrie Fisher]
  • X-Men: Apocalypse (2016; Action, Adventure, Fantasy, Sci-Fi) Since the dawn of civilization, he was worshiped as a god. Apocalypse, the first and most powerful mutant from Marvel's X-Men universe, amassed the powers of many other mutants, becoming immortal and invincible. Upon awakening after thousands of years, he is disillusioned with the world as he finds it and recruits a team of powerful mutants, including a disheartened Magneto, to cleanse mankind and create a new world order, over which he will reign. As the fate of the Earth hangs in the balance, Raven with the help of Professor X must lead a team of young X-Men to stop their greatest nemesis and save mankind from complete destruction. [D: Bryan Singer; A: Oscar Isaac, Jennifer Lawrence, Michael Fassbender]
  • Youth (2015; Drama) Fred and Mick, two old friends, are on vacation in an elegant hotel at the foot of the Alps. Fred, a composer and conductor, is now retired. Mick, a film director, is still working. They look with curiosity and tenderness on their children's confused lives, Mick's enthusiastic young writers, and the other hotel guests. While Mick scrambles to finish the screenplay for what he imagines will be his last important film, Fred has no intention of resuming his musical career. But someone wants at all costs to hear him conduct again. [D: Paolo Sorrentino; A: The Retrosettes, Gabriella Belisario, Harvey Keitel]
  • Zipper (2015; Drama, Thriller) Sam Ellis is a man on the rise - a federal prosecutor on the cusp of a bright political future. But what was meant to be a one-time experience with a high-end escort instead turns into a growing addiction. His moral compass unraveling, his new demon threatens to destroy his life, family and career. [D: Mora Stephens; A: Patrick Wilson, Lena Headey, Ray Winstone]

Finalmente, el conteo de pendientes por fecha:

(Sep-2010)    9   2   1
(Dic-2010)   12   5   1
(Abr-2011)   23  22  17   4
(Ago-2011)   11  11  11  11   4
(Ene-2012)   17  17  17  17  11   3
(Jul-2012)   15  15  15  15  14  11
(Nov-2012)   12  11  11  11  11  11   6
(Feb-2013)   19  19  16  15  14  14   8   2
(Jun-2013)       19  18  16  15  15  15  11   2
(Sep-2013)           18  18  18  18  17  16   8
(Dic-2013)               14  14  12  12  12  12   4
(Abr-2014)                    9   9   8   8   8   3
(Jul-2014)                       10  10  10  10  10
(Nov-2014)                           24  22  22  22
(Feb-2015)                               13  13  13
(Jun-2015)                                   16  16
(Dic-2015)                                       21
Total:      118 121 125 121 110 103 100  94  91  89

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Google’s OnHub is a bit of a mystery. Google shipped us this box—well, this cylinder—but it won’t really talk about what’s in it or why it exists. Today, it’s a Wi-Fi router from Google; tomorrow it might be something totally different. But it’s also a funny glowing cylinder with way too much processing power for its own good, a boatload of antennas, and an ever-present cloud connection to a Google update server so that it can evolve at will. OnHub is a tiny bundle of potential and no one really knows what it will turn into.

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A few days before Thanksgiving, George Hotz, a 26-year-old hacker, invites me to his house in San Francisco to check out a project he’s been working on. He says it’s a self-driving car that he had built in about a month. The claim seems absurd. But when I turn up that morning, in his garage there’s a white 2016 Acura ILX outfitted with a laser-based radar (lidar) system on the roof and a camera mounted near the rearview mirror. A tangle of electronics is attached to a wooden board where the glove compartment used to be, a joystick protrudes where you’d usually find a gearshift, and a 21.5-inch screen is attached to the center of the dash. “Tesla only has a 17-inch screen,” Hotz says.

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Daniel Holbach


I’m very excited about UbuCon Summit which will bring many many Ubuntu people from all parts of its community together in January. David Planella did a great job explaining why this event is going to be just fantastic.

I look forward to meeting everyone and particularly look forward to what we’ve got to show in terms of Snappy Ubuntu Core.

Manik Taneja and Sergio Schvezov

We are going to have Manik Taneja and Sergio Schvezov there who are going to give the following talk:

Internet of Things gets ‘snappy’ with Ubuntu Core

Snappy Ubuntu Core is the new rendition of Ubuntu, designed from the ground up to power the next generation of IoT devices. The same Ubuntu and its vast ecosystem, but delivered in a leaner form, with state-of-the art security and reliable update mechanisms to ensure devices and apps are always up-to-date.

This talk will introduce Ubuntu Core, the technologies of its foundations and the developer experience with Snapcraft. We will also discuss how public and branded stores can kickstart a thriving app ecosystem and how Ubuntu meets the needs of connected device manufacturers, entrepreneurs and innovators.

And there’s more! Sergio Schvezov will also give the following workshop:

Hands-on demo: creating Ubuntu snaps with Snapcraft

Overview the snapcraft features and demo how easily a snap can be created using multiple parts from different sources. We will also show how to create a plugin for unhandled source types.

In addition to that we are going to have a few nice things at our booth, so we can show give you a Snappy experience there as well.

If you want to find out more, like check the entire schedule or register for the event, do it at

I’m looking forward to seeing you there! </p>
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