FreeBSD beginner (NetBSD advanced)
cswiger at mac.com
Thu Jul 15 12:28:18 PDT 2004
Wojciech Puchar wrote:
> i installed FreeBSD once to do quick performance tests, and at least in
> disk I/O and fair scheduling it's MUCH better (tested 4.10 and 5.1).
It's nice to be welcomed by higher performance when you switch OSes. :-)
> my questions:
> 1) what is Buf and Cache in top exactly? why buf on 96MB machine gets to
> near 20MB and never goes down? it's almost 1/4 of memory size.
Cache: number of pages used for VM-level disk caching
Buf: number of pages used for BIO-level disk caching
> 2) can i compile kernel with -march=pentium,pentium -O2 optimization?
> in NetBSD 2.0 doing -march=pentium produces kernel that doesn't boot at
> all, just resets.
If you want to tune your system, tweaking the options from GENERIC by removing
...will probably result in the greatest improvement, along with disabling
WITNESS and such if using -CURRENT. See "man tuning".
Using -march=pentium is likely to be worthwhile (assuming you don't have a 386
:-), higher than that may run into problems. Higher optimizations than -O are
not supported, although work is underway to fix the remaining code issues
(mainly in libalias used by NAT), as I understand.
If you want to try -O2, give it a shot, but you might consider using either
"-Os" rather than "-O2", or try "-O2 -fno-strict-aliasing".
> 3) how can i disable compiling, using etc.. all that LKM (KLD) stuff?
> i really prefer one static kernel.
Read the handbook on building the kernel.
> 4) is IPv6 working well? (i mean no crashes etc...) i will get real IPv6
> zone allocation soon and want to use it.
IPv6 seems to work well, yes.
> 5) what is used in FreeBSD for traffic management. NetBSD has altq -
> please just give me a name i will RTFM.
If you want to use that, ipf/altq should be available in -CURRENT. Otherwise,
ipfw & dummynet is another choice.
> 6) how to turn using serial port as console on i386? my home machine is
> headless, i'm using X terminals to access it.
See the handbook.
> 7) does FreeBSD support 2 CPUs on i386?
Sure. See the SMP section of the kernel config file.
> should i go to 4.10 or better 5.2.1? stability is really important to me.
4.10, unless there's a feature from -CURRENT that you don't want to live without.
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