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From: Lowell Gilbert <freebsd-questions-local@be-well.ilk.org>
To: <fredports@mufley.com>
Subject: Re: Performance Related Question
References: <8d801e895617b492ddf724b6ce980448@www.mufley.com>
 <op.ws6rcqqsg7njmm@michael-think>
 <95256df2d5f04884368acf0f73bb82d0@www.mufley.com>
 <alpine.BSF.2.00.1302271551320.57262@wonkity.com>
 <3e5f08a6797b963f947fa83cd208600b@www.mufley.com>
Date: Thu, 28 Feb 2013 16:27:08 -0500
In-Reply-To: <3e5f08a6797b963f947fa83cd208600b@www.mufley.com> (Frederico
 Costa's message of "Thu, 28 Feb 2013 18:23:02 +0000")
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Frederico Costa <fredports@mufley.com> writes:

> And thanks for the suggestions.
> I have now tested with -j option and i can confirm that my
> expectations are correct the Dual CPU dual core AMD completes the
> buildworld with -j4 in one hour only, while the intal core 2 does it
> in 1h30m

The ideal values for that parameter vary considerably with the balance
between number of cores, number of virtual cores, memory (amount and
speed) and disk throughput. If you want to optimize it, you'd need to
experiment. But it's not worth it; you can easily spend hours shaving a
couple of minutes off of your system build time.

> should i stick the -j option in the make.conf?

No. It sometimes causes problems with the install targets, and besides,
it makes the build output very confusing (so when you have a problem,
you always want to run without it).