Richard Fish schrieb: > On 8/21/06, Stefan G. Weichinger <[EMAIL PROTECTED]> wrote: >> Acer TM 634 >> P4-M 1.8GHz (cpu family : 15, model : 2) >> 512 MB RAM >> 30 GB 5200 rpm HDD > > It's all relative. I have a 2.1Ghz Core Duo with 2G of RAM and a > 160Gb HD, so *I* would consider your laptop, um, "underpowered". :-)
Oh my .... ;) So you see, it is even more important to choose the right flags with such an outdated box ;-) > But I also run with -Os. The fact is that some things will run > slightly faster at -Os than -O2, and some things will be slightly > slower. The same applies comparing -O3 to -O2, or -O3 to -Os; it all > depends on what you are doing at the moment. > > So you should not assume that -O3 is faster for some random task just > because it is "more optimized". It simply makes different trade-offs > than -O2 or -Os, and because of the way CPUs and caches work these > days, those trade-offs may help or hurt a particular segment of code. > > FYI, in all of the tests I did, the performance was within 10% of the > median. The real deciding factor for me now is that -Os seems to take > much less time and memory to compile than -O2 or -O3. And being a > ~arch user, time-to-compile is a nice thing to reduce. I am going the -Os-way now, using your script from your other posting. Thanks a lot for the information, Stefan -- gentoo-user@gentoo.org mailing list
