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15 second whirlwind test of 13 sandstorm apps

Posted by admin |

About 15 seconds evaluation time per app from Apps · Sandstorm Oasis, using sandstorm.io's demo account that is automatically created for you, try it out yourself - it is very quick and seamless!

Just select install for an app and you will get the option to try it out on their demo server.

I have starred my favorites below with ****, and I have not rated the other ones; they may still be good. Please note that 15 seconds of testing time per app is not a lot of time :)

The reason so many get stars is probably because I selected the ones I was interested in.

  • MediaGoblin - no bulk upload
  • Lychee - Photo manager with albums and drag-and-drop upload ****
  • Davros - OwnCloud compatible file manager with drag-and-drop and desktop clients, seems awesome ****
  • Telescope - posting of links
  • Hacker CMS - Disarmingly simple, actually quite nice ****
  • Tiny RSS reader - Works fine, can pick up feeds automatically from parsing HTML Pages, works at least with this blog! ****
  • Apache Wave - Old Google Wave, or new Google Wave I suppose.
  • Framadate - Your own doodle for scheduling meetings. confusing use of check marks and a bit worse handling of times than Doodle, but otherwise fine ****
  • Giftr - an app for coordinating your friends gift-giving to you, simple but probably does the job, hard to gauge in a single-user demo environment
  • Let's chat - "Error: remote exception: remote exception: remote exception: remote exception: remote exception: remote exception: connect(): Connection refused C++ location:(remote):?? type: disconnected"
  • Dillinger - Markdown editor works, but then again how could it not? It is basically all client side, nothing stored server side afaict.
  • FileDrop - Simple, can see use for it just between your own computers. The Hacker CMS and the Media Goblin could use this drag-and-drop stuff ****
  • Rocket chat - impressive, haven't tried the voice chat ****
     
Feb 06, 2016 01:45 | Comments (1)

Systems abstractions: Chef, Ansible, Puppet, Sandstorm.io, Docker, Saltstack & many more - what do they do?

Posted by admin |

Some initial thoughts about systems such as:

& many more - what do they do?

What they all have in common is that they in some fashion abstract away the previously tedious work of configuring whole systems, including operating system, libraries, configuration management and the applications running on top of it all. The operating system with its associated libraries, configurations and services should be made into a predictable and easily configurable component, that can be extended with more components.

The idea is to talk about functionality, often in these systems called a role, instead of having to care about the nitty-gritty of how to build up the complex sub systems needed to get to that point.

They do this by having modules, sometimes called recipes, playbooks or grains, that take all the non-important decisions for you, and leave you with a few parameters that actually influence what is different from your setup as compared to others.

The grand daddy I would say from my admittedly biased perspective, and the system I have experience with in this field is actually Buildout, a python system that builds up the functionality you need completely inside a directory of your choosing on the server, where everything you need runs. It does this by using something called recipes, short ready-made python programs that take a few parameters as input for configuring the component the way you want it. Buildout does however not configure the entire server, but is still very powerful.

As an example here chromanode-regtest-backend is a buildout I made a couple of months ago that builds and configures and runs the postgresql database, the node.js application server, the supervisord process runner, bitcoind, bitcoin-abe, chromanode and a number of custom scripts to make a self contained testing environment for bitcoin and colored coins applications, with scripted mining of blocks in an isolated regtest blockchain. Nothing runs as root but as a restricted user. If you delete the directory, it is all removed from your computer, and you can also have several instances in different directories and with one configuration directive you can offset their TCP ports so that they do not clobber each other. Foundation script here.

However buildout does not take care of the operating system or version updates, and it is now time for me to move on a bit and figure out what would be the best fit for the problems I'm facing now: Repeatable deployments and power and simplicity for developing new applications.

Feb 06, 2016 12:45

Expansion with ~ doesn't work in Obnam config files

Posted by admin |

Backups with Obnam

Expansion with ~ doesn't work in config files. On the Backups with Obnam page, you can read:

As an example, your first backup might have the following configuration:

obnam backup -r /media/backups/tomjon-repo ~ \
    --exclude ~/Downloads

...but that doesn't work in a config file:

exclude = ~/Downloads

Not working! Reason I guess: There is no shell to expand the ~ character. So you'll have to write:

exclude = /full/path/to/Downloads
Feb 05, 2016 11:34

An OS for Raspberry pi that does not corrupt the SD card?

Posted by admin |

Untested by me

 

IPE R2 – Industrial Perennial Environment Release 2 aims to be a blackout-proof Linux distribution-alike for the Raspberry PI. It is based on buildroot, and available both as an Image and as an SDK, where you can compile your own Image.


Read more: Link - IPE R2 | NutCom Services, Inc.

Feb 05, 2016 12:18

Sometimes ubuntu forgets to update the kernel on upgrade

Posted by admin |

On an Ubuntu 15.04 computer I could not install linux-headers for the right kernel versions. Turned out that the kernel installed was from an older Ubuntu, that did not have any corresponding kernel headers in the enabled repositories. Doing the apt-get update && apt-get upgrade dance made no difference.

Sneaky.

I did sudo apt-get install linux-generic and bob's your uncle.

 

This is a bug in the distribution upgrade script. You can install the correct kernel by running: sudo apt-get install linux-generic After a reboot you should have the 4.2 kernel.


Read more: Link - upgrade - Ubuntu kernel not updating with 15.10 - Ask Ubuntu

Feb 04, 2016 10:06

Cap'n proto

Posted by admin |

Cap'n Proto: Introduction

Something to do with protocol buffers and used as a general data channel in sandstorm.io . They themselves compare it favorably to google protocol buffers.

From their front page:

  • Incremental reads: It is easy to start processing a Cap’n Proto message before you have received all of it since outer objects appear entirely before inner objects (as opposed to most encodings, where outer objects encompass inner objects).
  • Random access: You can read just one field of a message without parsing the whole thing.
  • mmap: Read a large Cap’n Proto file by memory-mapping it. The OS won’t even read in the parts that you don’t access.
  • Inter-language communication: Calling C++ code from, say, Java or Python tends to be painful or slow. With Cap’n Proto, the two languages can easily operate on the same in-memory data structure.
  • Inter-process communication: Multiple processes running on the same machine can share a Cap’n Proto message via shared memory. No need to pipe data through the kernel. Calling another process can be just as fast and easy as calling another thread.
  • Arena allocation: Manipulating Protobuf objects tends to be bogged down by memory allocation, unless you are very careful about object reuse. Cap’n Proto objects are always allocated in an “arena” or “region” style, which is faster and promotes cache locality.
  • Tiny generated code: Protobuf generates dedicated parsing and serialization code for every message type, and this code tends to be enormous. Cap’n Proto generated code is smaller by an order of magnitude or more. In fact, usually it’s no more than some inline accessor methods!
  • Tiny runtime library: Due to the simplicity of the Cap’n Proto format, the runtime library can be much smaller.
Feb 04, 2016 09:00

Camlistore - an attempt to be the final resting place for your digital artifacts

Posted by admin |

All your photos, documents and other digital memories. Seems to be a bit rough around the edges still, not sure what to do with it once it is installed and stuff is imported. Images are not correctly rotated and other fineties. You can retrieve stuff via tags at least in the web browser. Will see if I'll explore it further.

It is all written in golang.

Camlistore is a set of open source formats, protocols, and software for modeling, storing, searching, sharing and synchronizing data in the post-PC era. Data may be files or objects, tweets or 5TB videos, and you can access it via a phone, browser or FUSE filesystem.

Camlistore (Content-Addressable Multi-Layer Indexed Storage) is under active development. If you're a programmer or fairly technical, you can probably get it up and running and get some utility out of it.

./bin/camlistored - for starting it

./bin/camput file -filenodes <your files> - for importing stuff (at least I did it that way)

./bin/cammount - for mounting a FUSE file system, but you cannot view much intelligible right now

Camlistore

Feb 04, 2016 08:55

The Zika virus and genetically modified mosquitoes

Posted by admin |

The Zika virus has spread to much of South America and it seems to be linked to brain damage in children born to infected mothers. An interesting debate on genetically modified mosquitoes has emerged:

If you search for Zika and genetic modification, at the moment you get links to articles from a number of news sites.

The more reputable ones (The Guardian, Bloomberg, etc.) write that genetically modified mosquitoes can help curb the spread of the Zika virus, while some other news sites that starts with "daily" in the UK, and Russia Today put forward the hypothesis that the genetically modified mosquito contributed to the spread of The Zika virus.

I do not know which hypothesis is correct, but the interesting thing is that what later will be proved true may greatly influence public attitudes to genetically modified organisms in general. If it appears that an increased use of these mosquitoes helps, it will be more sympathetic. If it is found that the mosquito has instead contributed to the epidemic, it might be a nail in the coffin for these experiments.

It seems that The Zika virus started moving from its previous heartland a few years ago by way of French Polynesia, and it may simply be that it is the jet age with its rapid transportation of humans over large distances that is the decisive factor behind the epidemic: The disease simply thrives in new areas, once it was offered the chance to get there.

That said, I do not know myself what is true in this case, but I think generally you should not genetically modify things that are:

  • Small
  • Can multiply


When you are unsure about the odds, take a look at the potential outcomes and it becomes quite clear that self-replicating stuff should not be meddled with, or created.'

And even if these modified mosquitoes aren't meant to breed in any meaningful sense, I am not convinced of the accuracy and stability of what has been created. I found this comment from Reddit and I can not assess the veracity of it, but it gives pause for thought and I find that the reasoning in it would be worthy of further exploration, with the help of someone more knowledgeable in the area:

 

sky_s

 

I'm personally pretty skeptical about the claims here, but you are the person who'se made the most incorrect claim I've read so far. Your claim that DNA is just DNA is too simplistic, and because of that you're just wrong. The way that most modifications on non-bacteria are made is by using either a polymerase or virus and then inserting an active sequence of DNA.

A few major concerns pop up with lab genetic modifications vs natural modification Firstly, most of the methods lead to DNA which is orders of magnitude more unstable than normal DNA, leading to horizontal transfer across the genome. This is in part due to the tails used needing to initially bind with foreign DNA, since they had to once readily unbind from something else for the initial implanting they are generally much more prone to repeating that later.

Another effect is that promotion is much more poorly regulated in GMO than natural mutations, since in nature besides base sequence there are steric effects that lead to proper regulation of promotion. These genes have sequences called promoters which bind due to some stimuli, and this binding allows for gene readout to begin after it. In viral techniques, there is a growing concern since it seems that in some cases active viral genes is also transferred to the organism. Sometimes it's because we thought they were inert, other times its just carelessness.

For animals the two primary sources of mutation are a single base pair being incorrectly replaced, or an extra insertion of a base pair. Both are much less likely to result in adverse steric effects and the cell can trigger aptosis if the error is particularly egregious. If not aptosis, then it still has to get through natural selection if a gamete mutated poorly. GMO is a very interesting technology, heck I've done bacterial genetic modification before, but I think it's far too underdeveloped a field for people to foolishly claim that it's indistinguishable from nature.

 

Feb 01, 2016 01:55

Zikaviruset & genetiskt modifierade myggor

Posted by admin |

Zikaviruset har spritt sig mycket i Sydamerika och det tycks som att det eventuellt kan orsaka hjärnskador på foster. Då har en intressant debatt om genetiskt modifierade myggor dykt upp:

Om man söker på Zika och genetisk modifiering på engelska just nu så får man träffar på artiklar från ett antal nyhetssajter.

De mer välrenommerade (The Guardian, Bloomberg, m fl) skriver att en genetiskt modifierad mygga kan hjälpa till med att stävja Zikavirusets framfart, medan några andra nyhetssajter som startar på "daily" i Storbritannien samt Russia Today framkastar hypotesen att den genetiskt modifierade myggan bidragit till spridningen av Zikaviruset.

Jag vet inte vilken hypotes som är riktig, men det intressanta är att vad som senare visar sig vara sant kan komma att kraftigt påverka allmänhetens inställning till genetiskt modifierade organismer: Om det visar sig att ett utökat bruk av dessa myggor hjälper, kommer den att bli mer välvilligt inställd, om det visar sig att myggan bidragit till epidemin kan det istället bli spiken i kistan för dessa experiment.

Det tycks som att Zikaviruset började röra på sig för några år sedan via Franska Polynesien och det kan helt enkelt vara så att det är jetåldern med sina snabba transporter som är faktorn bakom epidemin och att sjukdomen helt enkelt sprider sig över nya områden, inte för att den muterat eller bärs fram av genmanipulerade mygg, utan för att den nu fått fotfäste där och att det sedan går snabbt.

Som sagt, jag vet inte själv vad som är sant i det här fallet, men jag anser allmänt att man inte ska genmanipulera saker som är:

  • Små
  • Kan föröka sig

Och även om det är tänkt att den modifierade myggan inte ska föröka sig, så är jag inte övertygad om precisionen och stabiliten i hur de gör det hela. Hittade denna kommentar från Reddit och kan inte bedöma kompetensen på personen, men finner resonemanget värt att utforska med hjälp av någon kunnig i området:'

 

sky_s

 

I'm personally pretty skeptical about the claims here, but you are the person who'se made the most incorrect claim I've read so far. Your claim that DNA is just DNA is too simplistic, and because of that you're just wrong. The way that most modifications on non-bacteria are made is by using either a polymerase or virus and then inserting an active sequence of DNA.

A few major concerns pop up with lab genetic modifications vs natural modification Firstly, most of the methods lead to DNA which is orders of magnitude more unstable than normal DNA, leading to horizontal transfer across the genome. This is in part due to the tails used needing to initially bind with foreign DNA, since they had to once readily unbind from something else for the initial implanting they are generally much more prone to repeating that later.

Another effect is that promotion is much more poorly regulated in GMO than natural mutations, since in nature besides base sequence there are steric effects that lead to proper regulation of promotion. These genes have sequences called promoters which bind due to some stimuli, and this binding allows for gene readout to begin after it. In viral techniques, there is a growing concern since it seems that in some cases active viral genes is also transferred to the organism. Sometimes it's because we thought they were inert, other times its just carelessness.

For animals the two primary sources of mutation are a single base pair being incorrectly replaced, or an extra insertion of a base pair. Both are much less likely to result in adverse steric effects and the cell can trigger aptosis if the error is particularly egregious. If not aptosis, then it still has to get through natural selection if a gamete mutated poorly. GMO is a very interesting technology, heck I've done bacterial genetic modification before, but I think it's far too underdeveloped a field for people to foolishly claim that it's indistinguishable from nature.

Den kända mytkrossarsajten Snopes.com har skrivit om den Reddit-tråd ur vilken ovanstående kommentar är hämtad, och är skeptisk men inte kategoriskt avvisande till hypotesen: Zika Virus Caused by GMO Mosquitos? : snopes.com

Jan 31, 2016 11:25
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