-fomit-frame-pointer allows one extra register to be available for general-purpose use. I would assume this is really only a big deal on 32-bit x86, which is a bit starved for registers.* One would expect to see EBP no longer saved and adjusted on every function call, and probably some additional use of EBP in normal … Read more
Late entry! As I am likely to be searching for this in the future. There is a way to create copy/paste friendly Logger instances (granted this is almost never a good reason to do something!) by using Java 7’s MethodHandles class. private static final Logger LOGGER = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
The big O notation can be used to determine the growth rate of any function. In this case, it seems the book is not talking about the time complexity of computing the value, but about the value itself. And n(n+1)/2 is O(n^2).
Well, this is not C. And it is not an interpeter. So, yeah, pretty much totally inappropriate for this question. But what it is, is, a perfectly portable brainfuck compiler using C++0x variadic templates. You have to #define PROGRAM as a comma-separated sequence of C-syntax characters, because I could not extract them from the string … Read more
I copied your example and tried a little bit. Looks like if you stick with BFGS solver, after a few iteration the mu+ alpha * r will have some negative numbers, and that’s how you get the RuntimeWarning. The easiest fix I can think of is to switch to Nelder Mead solver. res = minimize(loglikelihood, … Read more
Yes, it is possible even without trickery: sacrifice accuracy for speed: the sqrt algorithm is iterative, re-implement with fewer iterations. lookup tables: either just for the start point of the iteration, or combined with interpolation to get you all the way there. caching: are you always sqrting the same limited set of values? if so, … Read more
The Oracle documentation has an excellent set of considerations for indexing choices: http://download.oracle.com/docs/cd/B28359_01/server.111/b28274/data_acc.htm#PFGRF004 Update for 19c: https://docs.oracle.com/en/database/oracle/oracle-database/19/tgdba/designing-and-developing-for-performance.html#GUID-99A7FD1B-CEFD-4E91-9486-2CBBFC2B7A1D Quoting: Consider indexing keys that are used frequently in WHERE clauses. Consider indexing keys that are used frequently to join tables in SQL statements. For more information on optimizing joins, see the section “Using Hash Clusters for Performance”. … Read more
The initialization of the elements allocated is controlled by the Allocator template argument, if you need it customized, customize it. But remember that this can get easily wind-up in the realm of dirty hacking, so use with caution. For instance, here is a pretty dirty solution. It will avoid the initialization, but it most probably … Read more
You can decorate a specific method (or a property getter/setter) with [MethodImpl(MethodImplOptions.NoOptimization)] and [MethodImpl(MethodImplOptions.NoInlining)], this will prevent the JITter from optimizing and inlining the method: [MethodImpl(MethodImplOptions.NoOptimization | MethodImplOptions.NoInlining)] private void MethodWhichShouldNotBeOptimized() { } However, there isn’t a way to apply this attribute to a block of code. Also NoOptimization attribute was added in .NET 3.5, … Read more
The whole point of a websocket connection is that you don’t ever have to ping the app for changes. Instead, the client just connects once and then the server can just directly send the client changes whenever they are available. The client never has to ask. The server just sends data when it’s available. For … Read more