c++ low-latency connectivity IV (nQuant) #2

(nQuant?)
This IV is heavy on low-level details of C/C++.
Q: Some tcp parameter to speed it up?
larger TCP window size

Q3a: Memory alignment – what if on the stack I declare 2 char variables?

Q3b: what if I put those 2 char variables in a struct?
Q3c: I have two 64-bit ints, one misalinged. When I use them what problems will I have?
Q1: If inside a member function I call “delete this”, what happens?
%%A: what if this “this” points to an object embedded as a field of an umbrella object? The deallocation would happen, but the destruction of the umbrella object may again deallocate it? This is confirmed in the FAQ (http://www.parashift.com/c++-faq-lite/delete-this.html)
%%A: how do we know the host obj is on heap, stack or global area
Q1b: To achieve heap-only, my class has private ctors and private op= and a static factory method. Will it work?
%%A: according to moreEffC++ P146, I would say yes, with certain caveats.
Q2: What’s reinterpret_cast vs dynamic_cast vs static_cast?
Q2b: What other casts are there?
Q: Placement new – can I use the regular “delete”?
%%A: probably no. Need to call the dtor manually? See P42 moreEffC++
Q: How does tcp handshake work?
A: http://en.wikipedia.org/wiki/Transmission_Control_Protocol#Connection_establishment
Q: tcp client to specify a non-random port? See post on bind()
Q: If a c++ app runs fine in debug build (compiler optimizations removed), but crashes in release mode, what guesses/clues do you have?
%%A: conditional compilation, like in my c# project
%%A: the compiler optimization leads to unusual execution speed between 2 threads, and cooks up a rare corner case
A: P260 [[art of concurrency]] says (in theory) it’s possible to hit threading error with optimization and no such error without optimization, which represents a bug in the compiler.’
A: P75 [[moving from c to c++]] hints that compiler optimization may lead to “critical bugs”
What’s the mutable keyword?

How does multicast work?

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