faster java compilation (was Re: linking performance

[Michael Stahl]

On 14/02/12 13:30, Noel Grandin wrote:
> 
> 
> On 2012-02-14 14:22, Michael Meeks wrote:
>> Perhaps; could it also be that we like to compile with gcc in some 
>> eight way parallel way, but when it comes to linking, we -really- 
>> don't want to bog our machine down in that way ? I wonder if we could 
>> explicitly limit parallelism of linking in some way (?) - we should 
>> prolly also do this for the java compilation which is often quite 
>> memory intensive and doesn't do well with umpteen in parallel (at 
>> least on my machine). 
> 
> Java compilation would be a hang of a lot faster if the build process 
> passed all of the java files to the compiler in one go.
> Java is really not meant to be compiled in a file-at-a-time-model, it is 
> meant to be compiled in a single-project-at-a-time go.

do we _really_ invoke javac once for each source file anywhere?

at least in gbuild it's invoked once per jar file (technically, per
JavaClassSet that the jar depends upon), which is the only sane way to
do it.