Hello Wenlong, You have addressed a very interesting topic. Let me share few ideas how to approach it:
1. The first thing I would expect to understand here is why we should care about "Hello, World" startup. SPEC jvm [0] startup scores are much more tempting to approach. Then one should compare the score with one of our competitors. Taking into account that 300 ms = 300 context switches I would not say that the number itself makes me unhappy about Harmony speed. 2. Due to some bureaucracy the following tempting [1] idea is still waiting for an experienced and accurate C coder to complete: * load classes into bootstrap class loader once * store the internal representation of classes as a memory mapped file; * next time, load the file if it exists. 4. If you don't like C, there are tunable things in a class library you may find using Gregory's JVMTI profiler [2]. [0] http://www.spec.org/jvm2008/ [1] a research shows +10% on "Hello, World" [2] two first attachments at https://issues.apache.org/jira/browse/HARMONY-4569 On Thu, Oct 23, 2008 at 12:29 AM, Tim Ellison <[EMAIL PROTECTED]> wrote: > > Wenlong Li (JIRA) wrote: > > The startup time is long for the simple helloworld program. On a Core > > 2 Quad-core processor, running the simple helloworld program will take > > more than 300 ms. > > Can we reduce the startup cost? > > Yes, I hope so ... concrete suggestions or analysis of startup costs are > welcome. > > Regards, > Tim -- With best regards, Alexei
