JIT-Compilation - Why? (ASPX specifically)

1. 2017-01-18 at 1:54 AM UTC

   #1
   

   aldra JIDF Controlled Opposition
   What's the benefit of JIT compilation?
   
   Specifically ASPX, by default, compiles a page the first time it's requested, then the compiled application segment is cached for a short period - further requests within that period go to the compiled segment. after expiry next request recompiles.
   
   what the hell is the benefit of this over pre-compiling things?
2. 2017-01-18 at 2:01 AM UTC

   #2
   

   aldra JIDF Controlled Opposition
   "Improvements in compiler technology can have an impact on existing programs. A better C compiler does not help you at all with programs already deployed. A better JIT-compiler will improve the performance of existing programs. The Java code you wrote ten years ago will run faster today."
   
   
   the only argument I've seen so far that makes any real sense
3. 2017-01-18 at 2:07 AM UTC

   #3
   Merlin Houston
   Makes it so you don't have to worry about compatability across different systems.
   
   ASPX is web pages right? So I wouldn't really consider that point to apply as much since it shouldn't affect how you create the asp template or however it works. Still it's why Java is so popular at big corporations.
4. 2017-01-18 at 2:11 AM UTC

   #4
   

   aldra JIDF Controlled Opposition
   java could be compiled at deployment, not runtime and still be cross platform
   
   profiling a website here and it's optimised extremely poorly; trying to work out how to clean it up but I didn't realise ASPX compiles chunks as they're requested which effectively punches the processor in the dick, hard and fast
5. 2017-01-21 at 9:17 PM UTC

   #5
   

   Lanny Bird of Courage

   Originally posted by aldra java could be compiled at deployment, not runtime and still be cross platform

   
   In java's case not every piece of code can be AoT compiled. Think about lambdas that form closures, you have to compile as many methods as times closures are generated which is unknowable before runtime. The more dynamic elements of the language must either be executed with an interpretative strategy (i.e. not reduced to native code until invocation) or compiled dynamically with one compilation per potential invocation.