I'm a relatively new employee at my current company, so I'm still "drinking from the fire hose" in terms of learning my way around the software and architecture. I've found myself dealing with some very large objects while writing unit tests, let's say for discussion a "SavedOrder", and I need to find where to find a particular piece of ...
Psyco is a specialising compiler for Python. The documentation states Psyco can and will use large amounts of memory. What are the main reasons for this memory usage? Is substantial memory overhead a feature of JIT compilers in general? Edit: Thanks for the answers so far. There are three likely contenders. Writing multiple spec...
Is there some way to see the native code produces by the JIT in a JVM? ...
I read somewhere that there is such optimization as Objects Inlining. It collocates two objects together if they have the same life-time scopes and there is a lot of reads between them. And GC also treat them as one to move from one generation to another. But I didn't find any mention about this optimization on java.sun.com to be sure ...
With a 150 *.dll ASP.NET website that's precompiled (updatable), what are some possible causes for a '% Time in JIT' that is often quite high (> 60%) and fluctuating long after the application has warmed-up (all functionality accessed) and without app restarts or file changes that might generate new assemblies? One would expect that th...
Writing fast native applications, with API calls and etc, in a modern cross platform programming language like C# would be awesome, wouldn't it? For example if you want to write a simple utility for helping IT people with installing things, which wouldn't need another components, in an easy and modern programming language? or if you want...
I am curious as to what happens in this situation: int i = 0; MessageBox.Show(i++.ToString ()); MessageBox.Show(i++.ToString ()); Array[i++] = Foo; Assuming this is the only way i is used in the method,does the JIT strip out i and replace it with literal values? ...
Outside of the ensuring that they cannot be changed (to the tune of a compiler error), does the JIT make any optimisations for const locals? Eg. public static int Main(string[] args) { const int timesToLoop = 50; for (int i=0; i<timesToLoop; i++) { // ... } } ...
Hi all, I'm reading up some material on whether Java can be faster than C++, and came across the following quote: "Java can be faster than C++ because JITs can inline over virtual function boundaries." (http://www.jelovic.com/articles/why%5Fjava%5Fis%5Fslow.htm) What does this mean? Does it mean that the JIT can inline virtual functi...
My Questions is Is there any regular expression engine which do Just-In-Time compiling during regex pattern parsing and use when matching/replacing the texts? or where can I learn JIT for i386 or x64 architecture? Why I need that is, I recently trying to benchmark python's built-in regex engine with normal C codes with around 10M da...
We seem to be subject to a strange bug in our Java environment. We've now had two occurrences of the same "can't happen" exception; in one case the problem occurred 42,551 times over a period of 48 minutes in a running process and then spontaneously cleared itself. The failing code is triggered by this line: return String.format("%1d%X...
Hi Do you know something just like this, but embeddable in a C program? ...
Hello, I am new with LLVM and i just played around with it for a couple of days. I generated a bc file with the online compiler on llvm.org and i would like to know if it was possible to load this bc file from a c or c++ program, execute the IR in the bc file with the llvm jit (programmatically in the c program) and get the result back...
Is the execution time (run-time) performance of code in a class that is loaded via reflection identical to the same code when the class is created using the new keyword? I say yes. But I was discussing this with a colleague who believes that the reflection oriented code is always slower. My view is that regardless of how the class wa...
Is it possible to manipulate the bytecode of a (signed) .NET program at runtime? E.g. by forcing the JIT to re-evalutate the IL? ...
I have heard that Java must use a JIT to be fast. This makes perfect sense when comparing to interpretation, but why can't someone make an ahead-of-time compiler that generates fast Java code? I know about gcj, but I don't think its output is typically faster than Hotspot for example. Are there things about the language that make this d...
I have the following .NET value types: [StructLayout(LayoutKind.Sequential)] public struct Date { public UInt16 V; } [StructLayout(LayoutKind.Sequential)] public struct StringPair { public String A; public String B; public String C; public Date D; public double V; } I have code that is passing a pointer to a v...
Recently I have observed the following interesting scenario in one of the application I'm developing using .NET 3.5. In this particualr application I have a singletion object which I access as a static variable. I exepected that the .NET run time should initializes this singleton object at the very first time I access it, but it seems th...
In a comment on this answer (which suggests using bit-shift operators over integer multiplication / division, for performance), I queried whether this would actually be faster. In the back of my mind is an idea that at some level, something will be clever enough to work out that >> 1 and / 2 are the same operation. However, I'm now wonde...
The canonical JVM implementation from Sun applies some pretty sophisticated optimization to bytecode to obtain near-native execution speeds after the code has been run a few times. The question is, why isn't this compiled code cached to disk for use during subsequent uses of the same function/class. As it stands, every time a program is ...