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...then 'No Bugs' Hare on Soft.ware might be the right place for you.
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When architecting a system, it is inevitable to make certain high-level design decisions.

Some of these decisions, if they’re wrong, can lead to the re-architecturing and re-writing of the whole system some months later, so there is an incentive to keep things rather generic. On the other hand, trying to make system too generic is just another recipe to disaster (usually expressed in terms of missed deadlines and unmanageable code).

IT Hares try to describe certain not-so-obvious architectural decisions, and some considerations which should be kept in mind while making them.

Design Decisions, page 2:

Ultimate DB Heresy: Single Modifying DB Connection. Part I. Performance (Part II. Scalability to follow)

Quote: “Dealing with transaction isolation is very far from being a picnic”
Another Quote: “One of such real-world systems was consistently processing over 30M real-world write transactions/day over one single DB connection, supporting ~100K simultaneous players.”

Distributed Databases 101: CAP, BASE, and Replication

Quote: “The worst case of inconsistency happens when row X in database A is modified (by a Client connected to datacenter A), and the same row X in database B is independently modified too (by a Client connected to datacenter B).”
Another Quote: “One way to avoid reports affecting operational DB, is via creating a read-only replica of our main operational DB – and running our reports off that replica.”

Databases 101: ACID, MVCC vs Locks, Transaction Isolation Levels, and Concurrency

Quote: “for larger-scale MOGs, functionality-wise it is common to have 4 different types of databases: transactional processing (OLTP) DBs, real-time reporting DBs, archive DBs, and analytical DBs (OLAP)”
Another Quote: “both MVCC-based and Lock-based DBMS issue locks (and therefore, both can cause all kinds of trouble such as deadlocks etc.); however, the difference lies with the number of locks issued by them.”

MMOG Server-Side. Eternal Linux-vs-Windows Debate

Quote: “Each server is only as secure as its admin”
Another Quote: “For cheaper servers, the difference between Windows and Linux can eat as much as 50% of the server rental price (though for those servers which are more or less optimal price-performance-wise observed difference was closer to 20-30%).”

Client-Side. Client Architecture Diagram, Threads, and Game Loop

Quote: “To have a good concurrency model, it is not strictly necessary to program in Erlang”
Another Quote: “Most of developers agree that FSM-based programming is beneficial in the medium- to long-run.”

Multi-threading at Business-logic Level is Considered Harmful

Quote: “However, the window for triviality is very narrow: for example, even going into two interrelated mutexes instead of one, can easily make multi-threading non-trivial”
Another Quote: “Technically you are able to jump to any point of your program, but the variables you see may (and if you have a multi-threaded bug – will) differ every time you jump there.”