SBR600- week2 - modifying -j values in .rpmmacros

To do this lab, I used a school computer in the open lab which has

intel Q9550 quad core cpu running at 2.83GHz and 4GB ram on it.

The result of rebuilding a package from its source RPM based on -j

value in ~./rpmmacros are the following:

%_smp_mflags -j0
error

%_smp_mflags -j1
real 0m31.406s
user 0m20.616s
sys 0m6.055s

%_smp_mflags -j2
real 0m24.657s
user 0m20.507s
sys 0m6.110s

%_smp_mflags -j3
real 0m22.559s
user 0m20.901s
sys 0m6.269s

%_smp_mflags -j4
real 0m21.480s
user 0m21.154s
sys 0m6.365s

%_smp_mflags -j5
real 0m21.636s
user 0m21.257s
sys 0m6.481s

%_smp_mflags -j6
real 0m21.430s
user 0m21.129s
sys 0m6.294s

commenting out of %_smp_mflags
real 0m21.650s
user 0m21.216s
sys 0m6.409s

The %_smp_mflag in .rpmmacros file is used as the make command

builds a package to set the number of jobs which will run at once.
As it is observed above, if the number of jobs sets to 0, it stops with
error. If there is no argument, it is considered as infinite jobs. I
didn't see any significant increment of performance after the value
of 4. 4 or higher value for the -j switch is best suited for the system
I tested.