“It's time to stop thinking of computer programming as a specialty subject. Schools should respect it as a fundamental skill.”

—Why High Schools Should Treat Computer Programming Like Algebra - Jordan Weissmann - The Atlantic

Open sourcing memkeys

We rely on memcache pretty heavily at Tumblr, with over 10TB of cache memory available across the stack. One of the things we’ve historically had a challenging time with at Tumblr is finding hot keys. A hot key is a memcache key getting dramatically more activity than other keys. This can have a significant performance impact on your cache backend.

We spent the past few days working on a C++ implementation of mctop*, which we’re happy to release today as memkeys. We do some pretty interesting stuff in memkeys to keep from dropping packets, some of which is documented in the wiki. I’m particularly proud of the striped lock-free queue implementation. In some basic benchmarks I found that memkeys dropped less than 2% of packets when seeing 1Gb/s of traffic. Additionally, the latency between a packet being picked up, parsed, processed, and reported on averages less than 1ms. Here is a screenshot of memkeys in action.

Screenshot

Interested in stuff like this? We’re hiring.

Footnote: Etsy created the excellent mctop tool which aims to be like unix top for memcache, showing you which keys are getting the most activity. Unfortunately (as noted in the known issues), mctop drops packets. It drops a lot of packets. This can be really problematic because depending on the packets being dropped, you’re getting a really incomplete view of your cache story.

Be careful not to antagonize the men!

I was the only woman on a team at a large software company. When I joined the team, I was the least experienced and so I had no problem doing the more basic work. However, I was surprised when two years later I was still being given the simple and boring assignments. The team had grown and I was now near the middle in terms of education and seniority.

Durring my performance review, I asked my boss what I could do to improve so that I could earn more interesting work. He explained to me that I was being held back by my agressive atitude. I spoke up at meetings, defended my opinions, and occasionally contradicted others when they were wrong. I was confused because I didn’t feel my behavior was different from my team mates. He explained that this behavior was welcome from some types of people, but I should learn to be soft spoken. There aren’t many women in my field so I have to be especially careful not to antagonize men who are not used to female coworkers. I immediately began the process to transfer to another team. I am still struck by the fact that he honestly appeared to believe this lecture was both appropriate and helpful.

The mobile phone application “Matatibu” will be able to diagnose malaria patients without a single prick on their skin, as well as showing them where the available treatment centre is located.

The Five Best Tools for Creating Videos Without Installing Software

Over the years I’ve published some lists and reviews of free tools for creating videos online. Quite a few of those tools have been for creating simple videos that are really just automated, audio slideshows. See Animoto for an example of this. There’s nothing inherently wrong with having your students use those tools, but at some point you will want to take your video projects to the next level. These are the five tools that I recommend for creating and editing videos without installing any special software.

Pixorial is the online video creation tool that I hear teachers talking about a lot lately. The thing that I like the most about Pixorial is that the video creation and editing tools are laid out in an intuitive user interface. Most users will never find themselves wondering what any of the editing tools do or what to click on next. To create a video in Pixorial you can upload pictures and raw video footage then organize that media into the sequence in which you want it to appear. You can insert transitions between elements by selecting them from the transitions gallery. If you would like to add a soundtrack to your production you can select one from the Pixorial gallery or upload your own audio files. Pixorial also makes it easy to add text to each picture or video that you upload. Just click on “overlay text” in the video editor when you’re viewing the element that you want to add text to. Pixorial offers a free plan to educators. The educators’ plan provides 30GB of free storage. Pixorial offers Android and iOS apps too.

WeVideo is a collaborative online video creation tool. In the video editor you can upload your own media clips or use stock media clips to produce your video. The video editor provides tools for trimming the length of display and or sound of each element you add to your video project. What makes WeVideo collaborative is that you can invite other people to create and edit with you. The WeVideo Google Drive app allows you to save all of your video projects in your Google Drive account. WeVideo also offers an Android app that students can use to capture images and video footage to add to their projects.

PowToon is a nice service for creating explanatory videos through a drag and drop process. The videos that you create feature digital paper cut-outs on a colorful background. Think of PowToon as an online tool for creating videos in the style made popular by Common Craft. PowToon provides drawings of people and objects that you can arrange on blank canvas. After adding your narration to the arrangement you can publish your video. PowToon’s free version limits your videos to 45 seconds.

Wideo is a service that allows anyone to create animated videos and Common Craft-style videos online. You can create an animated video on Wideo by dragging and dropping elements into place in the Wideo editor then setting the sequence of animations. Each element can be re-used as many times as you like and the timing of the animation of each image can individually adjusted. Wideo’s stock elements include text, cartoons, and drawings. You can also upload your own images and audio files to use in your videos.

WIDEOO REEL ENG NEW LOGO from Agustin Esperon on Vimeo.

Weavly provides a simple drag and drop interface that allows you to search for, trim and combine tracks without ever leaving the Weavly site. You can mix together video and audio from YouTube, Vine, and SoundCloud. You can also add animated GIFs from Loopcam, Tumblr, and Imgur. To start creating your Weavly video perform a search for video content. When you find a video clip that you like drag it to the Weavly editor where you can adjust the start and end times of the clip. Then move on to adding sounds by search for sounds and draggin them to the Weavly editor where you can again trim the start and end times. Finally, you can add some animated GIFs by searching for them and dragging them into the editor. You can repeat all of these steps as many times as you like to create your video.