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What is the runtime performance cost of a Docker container?
I'd like to comprehensively understand the run-time performance cost of a Docker container. I've found references to networking anecdotally being ~100µs slower .
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Why should I declare a virtual destructor for an abstract class in C++?
... to the interface, not a pointer to the concrete implementation. When they come to delete it, if the destructor is non-virtual, they will call the interface's destructor (or the compiler-provided default, if you didn't specify one), not the derived class's destructor. Instant memory leak.
For examp...
How to add a touch event to a UIView?
... It's not too bad, but I wish there were a block based API like github.com/neror/ftutils/blob/master/Headers/FTUtils/…. Xcode 4 does have support for adding/configuring gesture recognizers in Interface Builder, too.
– Nathan Eror
May 24 '12 at 16:03
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In log4j, does checking isDebugEnabled before logging improve performance?
...ment (checking isDebugEnabled()) is there to prevent potentially expensive computation of the log message when it involves invocation of the toString() methods of various objects and concatenating the results.
In the given example, the log message is a constant string, so letting the logger discard...
Why use pip over easy_install? [closed]
...s. pip can handle wheels; easy_install cannot.
Virtual environments (which come built-in with 3.4, or can be added to 2.6+/3.1+ with virtualenv) have become a very important and prominent tool (and recommended in the official docs); they include pip out of the box, but don't even work properly with ...
Want to find records with no associated records in Rails
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Calling C/C++ from Python?
...jects to Python, and vice-versa, using no special
tools -- just your C++ compiler. It is designed to wrap C++ interfaces
non-intrusively, so that you should not have to change the C++ code at
all in order to wrap it, making Boost.Python ideal for exposing
3rd-party libraries to Python. The l...
How to join (merge) data frames (inner, outer, left, right)
...) will work for these examples because R automatically joins the frames by common variable names, but you would most likely want to specify merge(df1, df2, by = "CustomerId") to make sure that you were matching on only the fields you desired. You can also use the by.x and by.y parameters if the mat...
Move an array element from one array position to another
...n a relatively limited example like this, and there is a nice split in the community over whether or not prototype modification is a good idea. Normally, iteration problems are the least concern, though.
– Reid
Mar 19 '13 at 3:24
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What is the gain from declaring a method as static
I've recently been looking through my warnings in Eclipse and come across this one:
9 Answers
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