On Tue, 2003-05-27 at 05:34, John R MacMillan wrote: > |> Are there any JITs that save what they do? [...] > > I've been told that IBM's JVM for iSeries (AS/400) does this, but I > don't know that first-hand.
Yes, I forgot about the AS/400 JVM. It has support for this or some variation on this notion. > |[...] You'd > |be amazed at how little of a net win this is. > > In general I agree, but I think there may be special cases where it > would be a win. > > For instruction sets that are relatively difficult to compile for (eg. > IA-64), it might be useful, for example. From what I've seen of IA-64 > JVMs, the compilation time often swamps the runtime, making client-side > apps in particular run better without it. I suspect this is more a result of the JVM JIT's not being sufficiently adapted to IA-64 (something that likely won't happen until IA-64 has a large market share). A cleverly written IA-64 VM will generate EPIC instructions which simultaneously interpret byte codes, profile execution, and generate native code at the same time. (Well, perhaps it'd be ambitious to be able to do more than 2 of those at any given point in time.) Of course, that is far more complex than simply caching the JIT'd code, so I could see where a cache might yield a helpful interim solution.. > It also could be useful in the more limited case of apps that are > short-lived and need/want to start up quickly. Yes, although in those cases you likely would want to just compile the app to native code. -- Christopher Smith <[EMAIL PROTECTED]> ---------------------------------------------------------------------- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
