That reminds me of the "next great thing" in the PC world (which then was mostly Apple, with a few 8080 and z80 boxes thrown in) circa 1981 - UCSD Pascal. It created and ran byte code. It was slower than (insert favorite analogy here). Those that forget history...
I don't care how optimized your interpreter or virtual machine or whatever is - it's never gonna be faster than compiling to the native machine code. That's why MANTIS was (and probably still is) so slow. That's why Software AG had to come out with the NATURAL Optimizing Compiler. (It's actually pretty slick - the resulting byte/machine code object can run on z/OS, z/VSE, z/VM or BS2000/OSD, and older versions could run on WANG VS.) Later, Ray -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of McKown, John Sent: Wednesday July 19 2006 11:03 To: IBM-MAIN@BAMA.UA.EDU Subject: Re: Why is zSeries so CPU poor? > -----Original Message----- > From: IBM Mainframe Discussion List > [mailto:[EMAIL PROTECTED] On Behalf Of Kuredjian, Michael > Sent: Wednesday, July 19, 2006 12:59 PM > To: IBM-MAIN@BAMA.UA.EDU > Subject: Re: Why is zSeries so CPU poor? > > > It's an interpreted language. Again, not really. The Java source code is actually compiled to a binary form which is called "Java Byte Code". This byte code is similar in nature to a normal processor's instruction set. I guess you could say that the JVM "inteprets" the byte code. But I think of it more like the JVM includes a byte code emulator (like the old 1401 emulator). But, from what I can tell,the Java byte code doesn't match the zSeries instruction set very well. So it is relatively inefficient. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
