RFC: Value of New Section on Tools Build Time Expectations

[Christian Mauderer]

Am 21.10.18 um 19:07 schrieb Joel Sherrill:
> Hi
> 
> I am in the middle of reconfiguring my old (~2013 i7) laptop as an email
> and remote workstation for home. Between helping students and doing two
> Kick Starts in the past 6 weeks, VM configuration, disk space
> expectations, and time required to build the tools seem to be a topic
> that needs to be addressed. Under-configured VMs don't finish building
> or take a LONG time.
> 
> I am proposing that I gather performance and configuraton notes for
> building SPARC tools after downloading source on a few configurations:
> 
> + Laptop 2013 i7: Centos on VM
> + Laptop 2013 i7: MSYS2
> + Laptop 2013 i7: Cygwin
> + Laptop 2017 i7: Same three
> + 8 core Xeon Centos native
> + 12 core i7 Fedora native
> 
> One the 2017 7th generation i7, differences in VM configuration can
> result in the build time for sparc tools almost tripling.
> 
> Does this sound useful or confusing? I know it is potentially somewhat
> volatile information. But my old 3rd generation i7 CPU benchmark results
> are comparable to an i5 that is much newer. Plus my old i7 has an SSD
> which many newer i3/i5 laptops do not.
> 
> Feedback appreciated.
> 
> --joel
> 

Hello Joel,

in my experience, the biggest difference in the build time is the number
of cores (in a VM or on a real machine). The processor generation didn't
seem to have that much influence. But I never measured exact numbers.

It might would be a good idea to add some rough numbers somewhere (maybe
in the RSB-manual) so that a new user knows that he has to expect for
example roughly 4 to 6 hours on a single core or about 1/2 to 3/4 of an
hour on a 8 core Linux system. It might could be interesting to have
some rough numbers for other commonly used systems too (like MSYS2,
Cygwin, FreeBSD or MacOS).

I don't think that it is useful to compare processor generations. That
would be an information that would have to be updated on a regular basis
to have any use. I would only add some (few) examples.

If you find any big influences beneath number of cores (you mentioned VM
settings), it might would be worth adding a general section with tips
for speeding up the build process.

Best regards

Christian