Re: md mirror / ext3 / dual core performance strange phenomenon?

From: Alistair John Strachan
Date: Mon Aug 14 2006 - 10:46:39 EST

On Monday 14 August 2006 14:26, Erik Slagter wrote:
> On ma, 2006-08-14 at 23:22 +1000, Keith Owens wrote:
> > >BUT... starting from -j4 (and upwards) the compile time suddenly goes to
> > >3.5 minutes!
> >
> > Nothing to do with the disks, it is a design flaw in the kernel build
> > system. If you want a useful parallel make using -j<n>, set <n> to 3,
> > 4 or 5 higher than the real number of parallel jobs that you want. The
> > exact value to add depends on which kernel tree you are building. See
> >
> Okay, so it basically means I shouldn't worry here.
> Sorry for bothering, I couldn't come up with a proper search term...

I find that for mainline, using an odd number of jobs works better. I can get
my X2 3800+ to full saturation with -j5.


Final year Computer Science undergraduate.
1F2 55 South Clerk Street, Edinburgh, UK.
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