I ran some tests on my dual-Xeon machine to see what speedup using
parallel gmake.  After two builds to warm up the cache, I saw when
alternating gmake and gmake -j2:

gmake           0m57.207s
gmake -j2       0m44.305s
gmake           0m58.691s
gmake -j2       0m33.979s

As you can see, gmake -j2 is ~35% faster than gmake without -j. I will
be using -j from now on.  -j3 shaves another second off.

FYI, I also use ccache for compiles.

-- 
  Bruce Momjian  <bruce(at)momjian(dot)us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +

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Next:	From: Bruce Momjian	Date: 2010-11-27 22:30:11
	Subject: Re: What do these terms mean in the SOURCE CODE?
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	Subject: Re: Small documentation enhancement for default_tablespace