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Re: cross gcc-4.1.2-12 packages

On 6/21/07, Ingo Juergensmann <ij@2007.bluespice.org> wrote:
On Thu, Jun 21, 2007 at 10:14:10PM -0700, Brian Morris wrote:

> watching the g3 closely with top while the quadra compiles. It looks
> like compiling a routine the mac takes about 20 seconds, three seconds
> on the g3 compiling and 2 seconds of the network (lights flash on my
> hub-switch). So I figure simple arithmetic this is about the best one can
> do. that is even if compile took 0 seconds that could only be another
> 15% improvement (or with my g4 which is 3x the g3 then 10%).

If the m68k mac is needing 20s and the distcc setup needs 5 sec in total,
then this is 1/4 of the time the m68k needed, or other way round 400%

That's not what I meant !

Please consider this restatement:

without distcc, the mac takes 75 sec/page to compile c++.

with distcc, the complete compile takes 20 sec/page. of this 20 seconds
the g3 spends 3 seconds compiling and the network transfer takes 2 seconds.
thus the overhead for the mac is 15 seconds.

thus given a g4 that was 3x faster than the g3, it could only possibly reduce
this time to 18seconds (another 10%)

the 3.5 times improvement of the compile time is great, but it is not
even using more than 25% of the 250mhz g3. I wonder what the mac
is doing during the 15 seconds, for a one page routine. statistically it
is a very solid number, the example from the text i compiled about
a hundred routines and the number was not varying at all as Iwatched
it go for a while.

the overhead is in the mac somewhere. not in the network per se
(could be latency in the mac accessing the net though).

I have plan to get a comm slot e/net card and then my q630 could
take two cards (although the lcIII card in there now is need by q605),
when my budget allows. then I could test using two network cards to
increase the network speed. but yes that is not the bottleneck (or
limiting factor).


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