zouqiong wrote: > I am very happy to know a person who has a common goal with me :-) > > en, my research focus on how to get more useful information to guide > compile > thread > and garbage collector to optimize the data locality and code quality, > and my > interest > is how to use performance monitor to get profile , and i think few vitural > machine use the performance monitor to guide code optimization > automatic. Of > course, many paper > use PMU to guide the analysis.
There is one interesting trick that I learned at an IBM presentation that was done at MIT last year (apologies, I don't remember the name of the speaker) about the trick of "persisting" the runtime optimization information that the JVM discovers after the first few runs of a particular program. For server side software, the warm-up time is not a big deal, but for client side software, it's a huge deal if Eclipse (or your, ehm, firefox extension written in java <grin>) starts up in 0.5 seconds instead of 5. The idea, basically, is that the *very first* time an application is run, the JVM will profile it and optimize the bytecode -> native compilation and go on doing its normal hot-spot stuff... but then every now and then, or at shutdown, the JVM will write that info on disk, so that it will be possible for the *next* run to start with a "optimization profile" that is, so-to-speak, precompiled and doesn't have to be inferred from the runtime execution of the program. There are some issues with the approach, but I think it's a great idea and nothing that we, as a community, can't find an answer for. BTW, would be great to have those people here talking to us about those new JVM tricks they are doing in IBM for J9. -- Stefano. --------------------------------------------------------------------- Terms of use : http://incubator.apache.org/harmony/mailing.html To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
