[yocto] Build time data

[Tomas Frydrych]

On 12/04/12 01:30, Darren Hart wrote:
> Next up is storage. 

Indeed. In my experience by far the biggest limiting factor in the
builds is getting io bound. If you are not running a dedicated build
machine, it is well worth using a dedicated disk for the poky tmp dir;
assuming you have cpu time left, this leaves the machine completely
usable for other things.


> Now RAM, you will want about 2 GB of RAM per core, with a minimum of 4GB.

My experience does not bear this out at all; building Yocto on a 6 core
hyper threaded desktop machine I have never ever seen the system memory
use to get significantly over a 2GB mark (out of 8GB available), doing
Yocto build using 10 cores/threads.


On a custom desktop machine with i7-x990 3.47GHz, 8GB ram, quiet
conventional hard disks, letting poky use 10 cores/threads (so I can get
my work done while it does its own thing in the background), a fresh
build of core-image-minimal for beagleboard, with debug & profile tools
and test apps, takes 77 minutes.

Obviously, not anywhere near as fast as the Intel OTC Xenon beast, but
much cheaper HW, and for my purposes the build speed is well in a region
where it is no longer a productivity issue.

Tomas