And the good news is that XWiki gives you the choice (velocity, groovy, python and ruby for now with others coming)! :)
Thanks for the info -Vincent On Sep 17, 2009, at 10:39 PM, Niels Mayer wrote: > Too bad Groovy isn't in here: "Alternative Languages on a JVM" > http://www.azulsystems.com/events/javaone_2009/session/2009_J1_JVMLang.pdf > ... > >> Deeper Dive > >> Clojure - “almost close” > > ● Good: no obvious subroutine calls in inner loop > > ● Bad: Massive “ephemeral” object allocation - > > requires good GC > > ● But needs Escape Analysis to go really fast > > ● Ugly: fix-num overflow checks everywhere > > ● Turn off fix-nums: same speed as Java > > ● Weird “holes” - > > ● Not-optimized reflection calls here & there > > ● Can get reports on generated reflection calls > > 10 > > Deeper Dive > >> Jython - “almost close” > > ● Also has fix-num issue; massive allocation > > ● Some extra locks thrown in > >> JavaScript/Rhino - “almost close” > > ● All things are Doubles – not 'double' > > ● Same fix-num allocation issues as Clojure, Jython > > ● Otherwise looks pretty good (no fix-num checks) > >> JRuby – Missed The Metal > > ● Assuming CachingCallSite::call inlines > > ● Using -XX:+PrintInlining to determine > > ● But flag is lying: claims method inlined, but it's not > > 11 > > Common Issue – Fix-Nums > >> Huge allocation rate of “fix-nums” > > ● Allocation is not free > > ● Setting final fields cost a memory fence > > ● GC does NOT cost here > > ● i.e., object pooling would be a big loser > >> Could do much better with JIT > > ● Need “ultra-stupid” Escape Analysis > > ● Need some (easy) JIT tweaking > > ● e.g. Getting around Integer.valueOf(i) caching > > 12 > > JRuby – Missed The Metal > >> Each minor action dispatches via “call” > >> Assuming CachingCallSite::call inlines > > ● (and allows further inlining) > >> Using -XX:+PrintInlining to determine > >> But flag is lying: claims inlined, but it's not > > ● BimorphicInlining is 'guessing' wrong target > >> Confirmed w/GDB on X86 Java6 > >> Confirmed w/Azul profiler > > ● My 1st impression: can't be inlined ever > > > Niels > http://nielsmayer.com > _______________________________________________ > devs mailing list > [email protected] > http://lists.xwiki.org/mailman/listinfo/devs _______________________________________________ devs mailing list [email protected] http://lists.xwiki.org/mailman/listinfo/devs
