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uryvok z knizky Thinking, Fast and Slow od D. Kahnemana: "The principle of independent judgments (and decorrelated errors) has immediate applications for the conduct of meetings, an activity in which executives in organizations spend a great deal of their working days. A simple rule can help: before an issue is discussed, all members of the committee should be asked to write a very brief summary of their position. This procedure makes good use of the value of the diversity of knowledge and opinion in the group. The standard practice of open discussion gives too much weight to the opinions of those who speak early and assertively, causing others to line up behind them."

out of 5 dentists agree that multi-threaded programming is hard to get right. At the end of the day, all that the GIL guarantees is that MRI's native C implementations of Ruby methods will be executed atomically (but even this has caveats). ... So the GIL doesn't 'solve' thread-safety issues. ... One way that we work with hard problems is with good abstractions. ... We're seeing more and more abstractions around threads. An approach that's catching on in the Ruby community is the Actor model of concurrency, with the most popular implementation being Celluloid. Celluloid provides a great abstraction that marries concurrency primitives to Ruby's object model. Celluloid can't guarantee that your code will be thread-safe or free from race conditions, but it wraps up best practices. I encourage you give Celluloid a try.

A few years ago, I took on a freelance project to implement an Internet Explorer component in C++. I was billing a healthy hourly rate on other projects at the time, but this particular client insisted on a fixed price. In a bout of temporary insanity, I made an exception.... Every developer knows that accurate software estimation is not possible even when perfect information is available about project requirements (i.e. practically never).....

podobne nazory na estimate trvania taskov som cez vikend cital aj v tomto clanku https://techcrunch.com/2016/12/11/death-to-jira/ , odhady veru nie su easy

Z toho clanku "death to JIRA" vypichujem: For some reason many companies today seem to be terrified of the prospect of writing more than a couple of paragraphs of clear and simple prose. But a well-written 8-page document can define the nuances of a complicated system far better than a whole cumbersome flotilla of interlinked JIRA tickets. ... Feature planning is about communication. JIRA is fundamentally a terrible way to communicate the requirements of a complex system. Words in a row, if written well, will always be better. A v dost vela veciach suhlasim.

the last three versions of the program -- each 420,000 lines long-had just one error each. The last 11 versions of this software had a total of 17 errors. Commercial programs of equivalent complexity would have 5,000 errors. Take the upgrade of the software to permit the shuttle to navigate with Global Positioning Satellites, a change that involves just 1.5% of the program, or 6,366 lines of code. The specs for that one change run 2,500 pages, a volume thicker than a phone book. The specs for the current program fill 30 volumes and run 40,000 pages.

Ever since the announcement of the Raspberry Pi, sites all across the Internet have offered lots of interesting and challenging uses for this exciting device. Although all of those ideas are great, the most obvious and perhaps least glamorous use for the Raspberry Pi (RPi) is creating your perfect home server.

I do a lot of work on open source, but my most valuable contributions haven't been code. Writing a patch is the easiest part of open source. The truly hard stuff is all of the rest: bug trackers, mailing lists, documentation, and other management tasks. Here's some things I've learned along the way...

The first metric I was wondering about is the distribution of gems in Gemfiles. How many gems does a common Ruby developer use in their projects? The numbers are somewhat expected: the average number of gems per Gemfile is 113.08 with the standard deviation of 52.19.... The next question I had was how many of those gems contain at least one vulnerability? The numbers are staggering! 1,333 Gemfiles, or 66% of the total, are affected! I definitely didn't expect that two thirds of all projects would contain at least one publicly known vulnerability.

I've written server-side applications for a decade now, and monitoring the components of your application is critical but painful. What monitors the CPU and RAM usage of your custom daemons? What monitors Redis, MySQL, memcached and the other parts of your system to ensure they are all behaving normally? What if I told you you could do all that and set it up in less than 5 minutes?

has_many is an anti-pattern which leads straight to monolithic applications. However, a simple inversion can free us from its grasp. What is the first model you added to your application? Probably User, right? So, once you wrote user.rb and its corresponding tests, and committed it - why did you ever open that file up again to tell it about something that it did not need to know existed? Rails keeps you from reopening user.rb if you add a column to the User table, and this is good, right? So why, when you added a Posts table far away, did you open up User again to make it aware of Posts? Did the definition of being a user change? Did you did not realize you were violating the Open-Closed Principle, one of the 5 principles of SOLID design? Somewhere inside I bet you knew it felt dirty to keep opening up User and making it aware of things that it had been blissfully unaware of.

At 9:37AM PST, an authorized S3 team member using an established playbook executed a command which was intended to remove a small number of servers for one of the S3 subsystems that is used by the S3 billing process. Unfortunately, one of the inputs to the command was entered incorrectly and a larger set of servers was removed than intended.

Father Zosime claims that the electronic ID cards signal the second coming of Christ. He also believes that using a barcode for products purchased in the supermarket is a sign of the coming apocalypse. If the electronic ID cards are abolished, this group of religious representatives also plans to demand that Georgians no longer use the personal numbers on their IDs, or any identification number at all.

PiezoMAT proposes a new technology of high-resolution fingerprint sensors based on a matrix of interconnected piezoelectric nanowires (NWs). The sub-micron dimension of NWs allows for high spatial frequency sampling of every fingerprint feature, enabling extremely reliable fingerprint differentiation through detection of the smallest minutiae (pores and ridge shapes).

the spirit of modern society is one of intense equality, which is a torture in terms of envy, for when egalitarian ambitions circulate in societies that tell themselves that anyone can do anything, the experience of envy goes into over-drive. We don't envy everyone, we do so only when we think their advantages are within our reach. So when almost everything feels like it could be ours (but a lot never can be), the opportunities for envy grow dangerously large.

Oracle is massively ramping up audits of Java customers it claims are in breach of its licences - six years after it bought Sun Microsystems. A growing number of Oracle customers and partners have been approached by Larry Ellison's firm, which claims they are out of compliance on Java. The moment you, as an organisation, are delivering something where Java is distributed to end users - something more and more companies are doing by distributing apps through which customers can obtain products and services - that is not general-purpose any more… and Oracle wants to make money from that. Nestudoval som to dokladne, no verim,ze na Slovensko faktury tak skoro prichadzat nebudu :)

Nuz, dufajme... Resp. este inak: tu diskusiu o (ne)distribuovani Javy by sme mali dotiahnut do konca.

Web/app projects these days often have many distributed parts. It's not uncommon for groups to use the right tool for the job. The right tools are often something like the choice below. Redis for queuing, and caching. Elastic Search for searching, and log stash. Influxdb or RRD for timeseries. S3 for an object store. PostgreSQL for relational data with constraints, and validation via schemas. Celery for job queues. Kafka for a buffer of queues or stream processing. Exception logging with PostgreSQL (perhaps using Sentry) KDB for low latency analytics on your column oriented data. Mongo/ZODB for storing documents JSON (or mangodb for /dev/null replacement) SQLite for embedded. Neo4j for graph databases. RethinkDB for your realtime data, when data changes, other parts 'react'. ... For all the different nodes this could easily cost thousands a month, require lots of ops knowledge and support, and use up lots of electricity. To set all this up from scratch could cost one to four weeks of developer time depending on if they know the various stacks already. Perhaps you'd have ten nodes to support. Could you gain an ops advantage by using only PostgreSQL?

I was playing a bit with OrientDB because the licensing model is not that pricey as for Neo4j. Anyway, after having really bad experience (http://orientdbleaks.blogspot.com/) I returned back to CouchDB, although it's not a graph db. But while I was searching for more data, I found this: http://www.aptuz.com/blog/is-postgres-nosql-database-better-than-mongodb/ and this: https://www.arangodb.com/2015/10/benchmark-postgresql-mongodb-arangodb/ so I'm pondering with an idea to give postgres(no)sql a chance :)

The finger pads of people with adermatoglyphia are entirely flat-they have none of the arching or looping ridges that characterize the fingerprints of virtually all humans.

Fingerprints, as most of us know, are composed of whorls, loops and arches. But keep zooming in, and you'll find tiny, tiny sweat pores arranged in patterns equally unique. Scientists in Korea have found a new way to map those pores that could help identify decade-old fingerprint fragments.

++ http://www.business-standard.com/article/news-ians/new-fingerprint-method-to-catch-thieves-faster-114050100556_1.html

Workplace stress costs the U.S economy hundreds of billions of dollars per year and is prevalent across all types of organizations and workplaces. If you have adopted or are in the process of adopting the devops methodology and culture, chances are your software developers are burning out as well.

If you have studied computing science, then you know how to do complexity analysis. You'll know that iterating through a linked list is O(N), binary search is O(log(N)) and a hash table lookup is O(1). What if I told you that all of the above is wrong?

PostgreSQL is an open source multi-purpose relational database system which is widely used throughout the world. It is one huge system with the integrated subsystems, each of which has a particular complex feature and works with each other cooperatively. Although understanding of the internal mechanism is crucial for both administration and integration using PostgreSQL, its hugeness and complexity prevent it.