I have an ASP.NET applications with quite small number of pages. The problem I see is that the startup time is quite slow. As far as I can tell, most of the time is spent in JIT. Pre-compiling the applications seem not very helpful in reducing the #methods JIT as reported thru PerfMon. Does anybody know what I can do to reduce the startu...
I'm using LLVM-clang on Linux. Suppose in foo.cpp I have: struct Foo { int x, y; }; How can I create a function "magic" such that: typedef (Foo) SomeFunc(Foo a, Foo b); SomeFunc func = magic("struct Foo { int x, y; };"); so that: func(SomeFunc a, SomeFunc b); // returns a.x + b.y; ? Note: So basically, "magic" needs to tak...
Anything out there other than llvm ? libjit doesn't seem very active.. I need a really fast and stable jitter. Even at the expense of features.. (preferably under c++) ...
I always come across articles which claim that Java is interpreted. I know that Oracle's HotSpot JRE provides just-in-time compilation, however is this the case for a majority of desktop users? For example, if I download Java via: http://www.java.com/en/download, will this include a JIT Compiler? ...
According to the computer language benchmark game, the LuaJIT implementation seems to beat every other JIT-ed dynamic language (V8, Tracemonkey, PLT Scheme, Erlang HIPE) by an order of magnitude. I know that these benchmarks are not representative (as they say: "Which programming language implementations have the fastest benchmark prog...
I have the following two programs: long startTime = System.currentTimeMillis(); for (int i = 0; i < N; i++); long endTime = System.currentTimeMillis(); System.out.println("Elapsed time: " + (endTime - startTime) + " msecs"); and long startTime = System.currentTimeMillis(); for (long i = 0; i < N; i++); long endTime = System.currentTi...
Hi, I was thinking about a typical problem that is very JIT-able, but hard to approach with raw C. The scenario is setting up a series of function pointers that are going to be "composed" (as in maths function composition) once at runtime and then called lots and lots of times. Doing it the obvious way involves many virtual calls, that...
I am writing a JIT on ARM Linux that executes an instruction set that contains self-modifying code. The instruction set does not have any cache flush instructions (similar to x86 in that respect). If I write out some code to a page and then call mprotect on that page, is that sufficient to invalidate the instruction cache? Or do I also ...
I don't know if I'll pass all the necessary information here, but I've only been asked to post this question here and I'm not entirely onto the matter. There is a .NET Framework 2.0 application compiled in the Debug mode with the parameter jitDebugging set to true in app.config <system.windows.forms jitDebugging="true" /> After any c...
The idea is somewhat similar to what Apple has done in the OpenGL stack. I want to have that a bit more general. Basically, I want to have specialised and optimised variants of some code for some specific cases. In other words: I have given an algorithm/code for a function (let B = {0,1}) f : B^n -> B^m Now, I special a specific cas...
I just read that Android has a 450% performance improvement because it added a JIT compiler, I know what JIT is, but I don't really understand why is it faster than normal compiled code? or what's the difference with the older approach from the Android platform (the Java like run compiled bytecode). Thanks! EDIT: This is hugely interes...
I'm browsing through OpenJDK sources and cannot find the place where optimized code is replaced. I wonder how this can be done in protected mode, isn't it some kind of selfmodifing code which should be prevented by the OS? ...
I've heard this term used, but I'm not entirely sure what it means, so: What DOES it mean and what DOESN'T it mean? What are some examples of what IS and ISN'T microbenchmarking? What are the dangers of microbenchmarking and how do you avoid it? (or is it a good thing?) ...
I know C# and Java do. Anyone else know of any others? ...
I'm new to using Windows 7 on a development machine, and I have a development tool that's crashing on launch, and I don't get to see any error messages it throws, or get a chance to debug it, because it shows the Windows 7 dialog for crashed programs, where it says "Windows is checking for a solution..." I want to have my old school big...
Hi all, I was just watching the google IO videos and they talked about the JIT compiler they included in the android and showed a demo about performance improvements thanks to JIT compiler. I wondered what does exactly a JIT compiler do and wanted to hear from different people. So, What is the duty of a JIT compiler? Thanks all Than...
I am doing some optimizations on an MPEG decoder. To ensure my optimizations aren't breaking anything I have a test suite that benchmarks the entire codebase (both optimized and original) as well as verifying that they both produce identical results (basically just feeding a couple of different streams through the decoder and crc32 the o...
When running a Java 1.6 (1.6.0_03-b05) app I've added the -XX:+PrintCompilation flag. On the output for some methods, in particular some of those that I know are getting called a lot, I see the text made not entrant and made zombie. What do these mean? Best guess is that it's a decompilation step before recompiling either that method or...
Many VMS, JVM/LLVM/... have JITs -- as the code is being interpreted, x86 instructions are created on the fly and executed. If there something similar to this for FPGAS? Is there someway where as an FPGA is running, I reconfigure it? [If so, please provide project / paper links. If not, what is the technology bottleneck that prevents th...
Yes exactly what I want to do :) At least for a particular class. The problem is, I create a static instance of an object but I don not use it directly. Since I do some operations in the constructor ,like adding the object to a list, the constructor must be invoked at least once before I get the list. I guess that the compiler just opti...