On 2008.04.30., at 20:59, John Rose wrote: > On Apr 30, 2008, at 6:37 AM, John Wilson wrote: > >> I'm rather unsure about the value of making changes like this to the > >> JVM. The timescale from now to when they become useable is rather >> long >> (2-3 years to get into a released JVM then another 2-3 years before I >> can rely on most of my target audience having the JVM in production). > > That's how the JVM game has been played for 10 years now: Major > optimizations like loop transformation or compressed oops or fixnums > or escape analysis take years to work through the pipeline. Over > time, JVM performance increases as new features deploy, each one > after its own gestation period. Depending on the time scales your > project contemplates, it may or may not be useful to know what JVM > optimizations are in the pipeline. It is useful for language > implementors to know the directions JVM implementors are taking on > problems they care about, and useful for JVM implementors to talk > with their users about what optimizations are on the table. Today > we're talking about fixnums. A year or two ago we were talking > about other optimizations now delivered.
That pace is pretty natural. I remember reading in the Clock of The Long Now book how most dynamic systems consist of layers that operate at different paces. The book illustrated this with human civilization, fashion/art being the highest (fastest changing, least long-term power), nature being the lowest (slowest changing, but tectonic in long-term power and momentum), and there are few in between; the full list was: fashion, business, infrastructure, government, culture, nature. Those higher up get more immediate attention and focus from community, those lower down have more momentum and power. The ecosystems we work in (and on) in the IT industry are similarily layered even if they're admittedly smaller in scale than a full-blown civilization :-). JVM and its optimizations are infrastructure. It evolves slower than the layers built on top of it (frameworks/ libraries, applications), but the effect of the changes is big on the layers above it, and a good optimization will be significant for existing systems also even if they don't adapt to it explicitly. Oh well, I guess I'd better stop the offtopic musings... Attila. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "JVM Languages" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/jvm-languages?hl=en -~----------~----~----~----~------~----~------~--~---
