alt Hacker NewsA couple more that don't seem to be represented there. No mention of cause and effect, or the order in which different nodes perceive things happening? Anyway here's three which I think might be more relevant to designing and building software:
* Your system is not a distributed system
Multiple users connect, disconnect, and use your system at the same time, some of the code is running on your servers, some of it's in your partners' servers, some of it's in your storage layer, and some of it's running on your users' computers
* Your DB's ACID transactions are sufficient for distributed thinking
An ACID transaction lets you addUser() to your storage, either succeeding completely or failing completely, with no observable intermediate state. It does not let both your frontend and your storage layer addUser(), same with both your storage and your partner's storage.
* Your DB's transactions are ACID
Your DB vendors cannot build databases that are acceptably fast while running ACID. Therefore isolation is relaxed and transactions can commit through each other. Even if the DB itself was ACID, your ORM and/or programming style is likely breaking ACID independently of the DB configuration.
Replies
* You will have logs
Always gets me
> No mention of cause and effect, or the order in which different nodes perceive things happening?
8. The network is homogeneous
Often misconstrued as a recapitulation of “there is one administrator”
A homogenous system, such as a single node Java application, for instance usually provides very clear semantics for this.
Another one from my experience:
* Hardware is cheap.
So many services and daemons are running on your system and most of them believe that they have all the hardware for themselves, while the opposite is true. Designing to capitalize whole hardware while they are other processes which are fighting to do the same never ends well.
OTOH, being a good citizen on a crowded system makes life for everyone better. Both maintenance and performance-wise.