Re: Gcj binaries performance (arm-linux)
Andrew Haley <[email protected]>
| Newsgroups | gmane.comp.gcc.java.devel |
|---|---|
| Message-ID | <[email protected]> |
Andrew John Hughes wrote: > 2008/5/9 Andrew Haley <[email protected]>: >> Andrew John Hughes wrote: >> > 2008/4/29 ffileppo <[email protected]>: >> >> > >> >> > aph@debian:~$ /home/aph/gcc-4.3.0-RC-20080301-install/bin/gcj MyPanel.class -O --main=MyPanel >> >> > aph@debian:~$ ./a.out >> >> > Test "Bubble Sort" (Num loop: 100) >> >> > First loop time: 22 >> >> > Total time elapsed: 2197 >> >> > >> >> > aph@debian:~$ /home/aph/gcc-4.3.0-RC-20080301-install/bin/gcj MyPanel.class -O2 --main=MyPanel >> >> > aph@debian:~$ ./a.out >> >> > Test "Bubble Sort" (Num loop: 100) >> >> > First loop time: 20 >> >> > Total time elapsed: 1943 >> >> >> >> >>>> Thanks for your help Andrew, >> >> I'm getting good performance on target using -O / -O2 >> >> > >> >>> So does gcj default to no optimisation? This is what these results >> > suggest, as the -O version is about 18 times quicker. >> >> Yes, of course. That's standard for UNIX, as far as I'm aware: I don't >> think I've ever come across a compiler that optimized unless it was >> asked to. >> >> Andrew. >> > > That makes sense, especially as something like -O2 will make debugging harder > and ** probably has effect on some of the reflection properties of Java. ** I should bloody well hope not! Andrew.