open life blog

20 years later, what's left of the CAP theorem?

The CAP theorem was published in (party like it's...) 1999: Fox Armando, Brewer Eric A: Harvest, Yield, and Scalable Tolerant Systems.

Since its publication it has provided a beacon and rallying cry around which web scale distributed databases could be built and debated. It(s interpretation) has also evolved. Quite quickly the original 1999 formulation was abandoned, and from there it has further eroded as real world database implementations have provided ever more finer grained trade offs for navigating the space that - after all - was correctly mapped out by the CAP theorem.

Pick ANY two? Really?

Video x2: Measuring performance variability of EC2

I was recently invited to speak at Fwdays Highload in Kyiv. This was my first ever visit to Ukraine, so I was excited to go and visit this large and beautiful European capital. Over a thousand years ago Vikings would row their boats through the rivers in Russia, and take the Dniepr southward to Kyiv and ultimately Turkey. It was exciting to travel in the footsteps of my forefathers.

My talk isn't really MongoDB specific, rather about an EC2 performance tuning project we did in 2017:

impress.js 1.0 is released!

I have released impress.js v1.0. Impress.js is a framework for creating awesome 3D presentations with standard HTML5 and CSS. (Similar to Prezi + 3D and open source.)

From the release notes:

  • New plugin based architecture allows adding more features without bloating core src/impress.js file
  • Source files are in src/ and compiled into js/impress.js with npm run build. End users should continue to use js/impress.js as before.
  • 19 new plugins
  • Integrates impressConsole.js by default (press 'P' to open speaker console)
  • Markdown support for those that are too much in a hurry to type HTML

impress.js HowTo: Slides over a background image

A common and IMO cool way to create impress.js presentations, is to use some large background image for the entire presentation, then layout each slide over it. One of my first impress.js presentation was Selling Open Source 101 for Oscon 101. The presentation is inside a picture of a woman selling all kinds of stuff in a bazaar.

Next week I will present something about EC2 at HighLoad++ conference, and my presentation is flying over some clouds, of course.

3D rotations in CSS and impress.js

The compelling feature of impress.js is to animate your presentations in a 3D space. Earlier this year I spent some time trying to move from placing my slides in a 2D plane to doing something really cool and 3D. But I never really got beyond some simple tilts and turns, like you see at the end of the official demo as well. Somehow I couldn't figure out the logic of simple rotations around x, y, and z axes.

Impress.js: Community contributions is so much fun!

During June-July I had pretty much completed adding the features that I myself had in mind impress.js (as you might have read on this blog back then). Some of those features of course had been asked for multiple times by others as well, in particular the ability to define slide positions relative to the previous slide, was a popular request, with several pull requests proposing it as well. Now that I've added such a plugin, I have to say it is indeed much more convenient way of authoring presentations.

About the bookAbout this siteAcademicAmazonBeginnersBooksBuildBotBusiness modelsbzrCassandraCloudcloud computingclsCommunitycommunityleadershipsummitConsistencycoodiaryCopyrightCreative CommonscssDatabasesdataminingDatastaxDevOpsDrizzleDrupalEconomyelectronEthicsEurovisionFacebookFrosconFunnyGaleraGISgithubGnomeGovernanceHandlerSocketHigh AvailabilityimpressionistimpressjsInkscapeInternetJavaScriptjsonKDEKubuntuLicensingLinuxMaidanMaker cultureMariaDBmarkdownMEAN stackMepSQLMicrosoftMobileMongoDBMontyProgramMusicMySQLMySQL ClusterNerdsNodeNoSQLodbaOpen ContentOpen SourceOpenSQLCampOracleOSConPAMPPatentsPerconaperformancePersonalPhilosophyPHPPiratesPlanetDrupalPoliticsPostgreSQLPresalespresentationsPress releasesProgrammingRed HatReplicationSeveralninesSillySkySQLSolonSunSybaseSymbiansysbenchtalksTechnicalTechnologyThe making ofTungstenTwitterUbuntuvolcanoWeb2.0WikipediaWork from HomexmlYouTube