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Premature and/or over-optimization is often claimed to be a root of most evil in the programming world. However, what to do when optimization IS neccessary?

IT Hares discuss certain not-so-trivial optimization techniques. It doesn’t mean that you should use them at all costs (and most likely, you don’t); however, if you do have a reason to optimize – this information may be handy.

Optimizations, page 1:

‘Speedy Gonzales’ Serializing (Re)Actors via Allocators

Quote: “Allocator-based serialization for (Re)Actors is extremely fast (for x64 – around tens of ms per 100MB of state)”
Another Quote: “Per-(Re)Actor allocators can be implemented without any changes within (Re)Actor itself (i.e. all the necessary changes can be confined to Infrastructure Code).”

Parallel STL for Newbies: Reduce and Independent Modifications

Quote: “with std::reduce() such code, while it compiles at least under MSVC, MAY occasionally provide wrong results”
Another Quote: “if you happen to need something beyond that – take a deep breath and allocate at least several months to understand how does parallelism really work under the hood.”

Using Parallel <algorithm> Without a Clue: 90x Performance Loss Instead of 8x Gain

Abstract: “I made an experiment which demonstrates Big Fat Dangers(tm) of implying that parallelization can be made as simple as just adding a policy parameter to your std:: call.”
Quote: “it is still necessary to understand what we’re doing”

OLTP Database Optimization 102 – DIY Heterogeneous Replication (Part II)

Quote: “The point of Super-Replica is that it is a replica Slave DB which is larger than original Master DB”
Another Quote: “this “don’t write some HISTORICAL data to Master DB” approach can easily allow to reduce the load on the Master OLTP DB by a factor of 2x-3x”

OLTP Optimization 102: DYI Heterogeneous Replication. Part I (Basics)

Quote: “there are still several Big Fat Reasons™ to use DIY replicas”
Another Quote: “With the Replication Messages described above, it is ok to apply Replication Messages to Slave DB which is newer than exactly necessary.”