Re: Introductory message

["Fabio M. De Francesco" <fmdefrancesco@gmail.com>]

On mercoledì 8 marzo 2023 18:13:33 CET Ira Weiny wrote:
> Julia Lawall wrote:
> > On Wed, 8 Mar 2023, Sumitra Sharma wrote:
> > > Hi I am Sumitra Sharma, an outreachy applicant. This is my first time
> > > applying to outreachy and linux-kernel. I am currently working on
> > > setting up the environment. I observed that building the kernel i.e.
> > > running "make -j2" command itself is taking a lot of time. I would
> > > appreciate some suggestions on it.
> > 
> > I think it would take a lot of time...
> 
> Also:
> 
> -j is an option which chooses how many threads to build in parallel.
> 
> If you have enough cores on your machine you could increase '2' to
> something larger.
> 

Sumitra,

That "something larger" can be calculated with a rule of thumb and then 
adapted to your necessities...

Look at /proc/cpuinfo if you don't know how many cores you have in your 
system...

# cat /proc/cpuinfo | grep processor
processor: 0
processor: 1
processor: 2
processor: 3
processor: 4
processor: 5
processor: 6
processor: 7
processor: 8
processor: 9
processor: 10
processor: 11

The output shows that I'm using a 12 core SMT system (https://
en.wikipedia.org/wiki/Simultaneous_multithreading).

So "-j12" is my usual choice for building a kernel in the host, minus the 
number of SMT cores reserved for running VMs.

Thanks,

Fabio