Question about cc flags in buildkernel

[Kirk Strauser]

On Monday 07 March 2005 21:48, Bernd Walter wrote:

> There is no speed influence by this option. 

Thanks for the explanation.  I wasn't sure, and it was nice to get a bit of 
confirmation.

> How did you compare speed?

It's more of a general observation: everything is just slow, slow, slow.  
For example, loading the man page for 'zshall' (from the shells/zsh port) 
takes most of a minute:

   # time man zshall > /dev/null
   Formatting page, please wait...Done.
   man zshall > /dev/null  47.39s user 0.99s system 93% cpu 51.523 total

during which troff and grotty are using 100% of the CPU.  SSH connections to 
it take a long time to start:

   $ time ssh gopher exit
   ssh gopher exit  0.04s user 0.03s system 0% cpu 7.675 total

If I run that with "-v", I can see that it spends most of that time in 
"Entering interactive session."  The hard drive isn't completely horrible 
(~8MB sustained transfers at less than 8% CPU usage), and it has 3 fxp NICs 
that barely register under heavy network load.  I installed 256MB of RAM 
(with 2MB of L2 cache, I think), and it's currently only 12KB into swap.  
In other words, by every metric I can think of, it appears the bottleneck 
is that the CPU is dog slow.

> If it's just from compile time, you shouldn't forget that gcc-3 is much
> slower than the older gcc and that compiling for alpha is a much harder
> job than compiling for i386.

Compile times don't really bother me; I launch big jobs and then walk away 
from it until they're done.  That's also why I was using the higher-order 
optimization flags.  They make the compiles quite a bit slower, but the 
results usually seem to be worth it (which here means "less painful").

I'm really not expecting miracles from this little machine, but my K6/333 
laptop with less RAM and a 2.5" IDE harddrive smokes it in every way.  I 
was sort of hoping I'd found the "aha!" detail that would account for the 
awful performance.
-- 
Kirk Strauser
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