Performance Related Question

[Michael Ross]

On Wed, 27 Feb 2013 23:38:34 +0100, Frederico Costa <fredports at mufley.com>  
wrote:

> On 2013-02-27 22:27, Michael Ross wrote:
>> If I read you right, you didn't ``make -jX buildworld'',
>> with X being the number of processes to spawn,
>> so you used just one core on either machine.
>>  Buildworld does a lot of I/O, so disk speed is relevant.
>
> Yes, i just made "make buildworld".
>
> So i should use make -j2 on the S1(dual core) and -j4 on S2 (2xdualcore)?
>
> And it also makes sense what you say about the I/O.
>
> i will start another to see the results.
>

Maybe try higher settings.
Handbook ( http://www.freebsd.org/doc/handbook/makeworld.html ) says:


	However, since much of the compiling process is I/O bound rather than CPU  
bound, it is also useful on single CPU machines.

	On a typical single-CPU machine, run:
	# make -j4 buildworld

	make(1) will then have up to 4 processes running at any one time.  
Empirical evidence posted to the mailing lists shows this generally gives  
the best performance benefit.

	On a multi-CPU machine using an SMP configured kernel, try values between  
6 and 10 and see how they speed things up.




> Thanks
>
> fred
>
>> On Wed, 27 Feb 2013 23:05:44 +0100, Frederico Costa
>> <fredports at mufley.com>  wrote:
>>
>>> Hi everyone...
>>>  I have a kind of interesting question when comes to performance of
>>> FreeBSD in different HW. i am not trying to come up with a scientific
>>> reason for measuring performance. :-)
>>>  It is just a curiosity, and of course to see if i understand it and
>>> improve performance of my systems.
>>>  i am running 2 systems at the moment, lets call them S1 and S2,
>>> running FreeBSD 9.1-RELEASE-p1 amd64:
>>>  S1:
>>> Intel Core2 Duo E6550 @ 2.33GHz
>>> 2GB RAM
>>> 500GB disk (not important probably just for reference)
>>>  S2:
>>> 2x Dual-Core AMD Opteron 2216 2.4GHz
>>> 14GB Ram
>>> 320GB disk (not important probably just for reference)
>>>  Both the systems are running more or less the same sw, apache, imap
>>> server, postfix, and the needed perl/php/python and running very light
>>>   load. Also both are using a GENERIC kernel and not running X, they  
>>> are
>>> just text based :-)
>>>   From cpubenchmark.net the cpu performance index are for s1: 1501 and
>>> s2: 1518, so very similar.
>>>  As i felt the AMD system seemed slower when comes to compiling, i just
>>> done a "performance test" which was "make buildworld" on both of
>>> systems from scratch and the times are:
>>>  S1: 2h 12m
>>> S2: 2h 59m
>>>
>>  If I read you right, you didn't ``make -jX buildworld'',
>> with X being the number of processes to spawn,
>> so you used just one core on either machine.
>>  Buildworld does a lot of I/O, so disk speed is relevant.
>>   Regards,
>>  Michael